Phaclia integrifolia scorpioid inflorescences with purple flowers, common in the Hydrophyllaceae family Page Last Updated May 5, 2026.
Introduction to the Hydrophyllaceae Family
When you learn to identify the Hydrophyllaceae family, you will quickly see some of their similarities with the Boraginaceae, which they were once included as a subfamily of until 2016.
Of all the small families split out of the Boraginaceae, this one looks the most like it, with its pretty blue and purple scorpioid cymes, especially my favorite genus Phacelia. I love their flowers, but I also love the stiff, often glandular hairs, divided leaves, and the interesting scents of the foliage in certain species, which some may consider unpleasant, but then again, for some reason I have always been biased; I tend to love smelly plants.
Common Botanical Description of the Hydrophyllaceae Family
If you’re new to plant morphology, this guide is a perfect beginner’s description, with no need to know any scientific jargon. Below this section is additional information on uses and morphology photos to help you identify the family, followed by pictures of individual species found in North America. But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Descriptionbelow the images for highly detailed scientific descriptions and genus-level distribution data.
Leaves and Stems of the Hydrophyllaceae: They are always herbs that grow from taproots and are often stiff or sticky-hairy and may have a noticeable scent (pleasant or not). The leaves are found on stems and at the base, rarely one or the other, and are simple (undivided) or, more often, divided into pairs of leaflets in a compound leaf and may be arranged in opposite pairs or alternately along the stem. Leaf margins may be smooth, toothed, or lobed.
Flowers of the Hydrophyllaceae: Flowers contain both male (stamens) and female (ovary, style, stigma) parts in the same flower (bisexual). They are typically arranged in coiled clusters, and their parts are typically in 5s with 5 petals and a fused calyx with 5 lobes. The flowers are often blue to violet in color and often have scaly appendages inside their tubes.
Reproductive Features of the Hydrophyllaceae: There are 5 stamens, often attached inside the floral tube with widened or appendaged bases. The ovary is superior (sits above the attachment of the petals) with a single terminal style that is usually divided into 2 lobes.
Fruits of the Hydrophyllaceae: The fruits are dry capsules that typically split apart on two valves to release their seeds.
Uses of Hydrophyllaceae
Several members of the Hydrophyllaceae are used ornamentally, especially in shade gardens, as well as for pollinator gardens and for use in erosion control. They also produce edible young shoots and roots that were historically used by Native Americans (e.g., Hydrophyllum species) and were also used medicinally for treating mouth sores and diarrhea.
Wildlife & Ecological Values of the Hydrophyllaceae Family
The Hydrophyllaceae family provides important nectar and pollen for native pollinators like bumblebees and long-tongued bees. They also are important early-season food sources and many aid in ecological succession by stabilizing soils and slopes.
Morphology of Hydrophyllaceae in North America
So far, I have only photographed the Phacelia genus, which is the most common and representative genus in the family, so all of these morphology photos are from that genus.
Learn how to identify the Hydrophyllaceae family with these morphology photos
Some Hydrophyllaceae Species Found in North America
Phacelia bipinnatifida—Purple Phacelia
The purple phacelia is a biennial herb up to 61 cm tall with showy rotate lavender-blue flowers up to 2 cm across, with appendaged stamens that often look fuzzy. It is typically found growing in cool moist woods and is native to the southeastern United States; this one was in a forest in Georgia.
Phacelia congesta—Blue Curls
Blue curls is a leafy annual or biennial 30-90 cm tall with purple to lavender-blue deeply lobed flowers with stamens that extend beyond the lobes. Flowers occur in heavily congested scorpioid cymes, which uncurl as the flowers bloom. Leaves are deeply cut and may appear rough. It is native to New Mexico, Oklahoma, and Texas in the United States and south into northern Mexico.
Phacelia crenulata—Notch Leaf Scorpionweed
This species is an aromatic annual, up to 80 cm tall, coated with stiff, glandular hairs. Leaves are oblong with wavy edges and get smaller up the stem. Flowers are purple or blue and may have a white throat. Stamens and style extend past the flower lobes. This native species has a disjunct distribution, found in the southwestern USA and northern Mexico but also in Peru, Bolivia, and Chile in South America.
Phacelia hirsuta—Fuzzy Phacelia
Fuzzy phacelia is a small native annual known for its dense covering of stiff but non-glandular hairs. It only grows to about 45 cm tall, may or may not be branched, and the leaves are alternately arranged and deeply lobed to pinnately compound. This cute little Phacelia is an endemic native of the south-central United States; I found this one in Arkansas.
Phacelia integrifolia—Gypsum Phacelia
People often easily identify this native Phacelia by its glandular hairs, which most find malodorous (but not me!) and sticky to the touch. It has leafy stems with simple leaves with crenate margins that often fold to the back of the leaf. It has the usual purplish to bluish scorpioid cymes of the family. It is native to the southwestern and south-central USA and northern Mexico, but most populations appear to be concentrated around New Mexico.
Phacelia linearis—Linearleaf Phacelia
This Phacelia is native to the Pacific Northwest of the USA and British Columbia and Alberta, Canada. It is easily identified by its location as well as its linear leaves, which are not common in the genus and are just visible (blurry) beneath the flower in this photo.
Phacelia popei—Pope’s Phacelia
This lovely Phacelia is one of my favorites, for its intense purple (sometimes pink) flowers in the usual scorpioid cymes. It is an annual that only grows to about 40 cm tall with leaves that range from “normal” to rather wide and pinnately divided. It is a somewhat rare species, found only in New Mexico and western Texas and just south of the border into northern Mexico.
Scientific Botanical Description of the Hydrophyllaceae
Habit & Leaf Form of the Hydrophyllaceae Family
The Hydrophyllaceae are annual, biennial, or perennial herbs growing from taproots with erect to prostrate stems, usually with an indumentum that is scabrid, hispid, or glandularly hairy, and sometimes the hairs can sting (e.g., as in Phacelia) and often have noticeable scents, from pleasant to unpleasant.
Leaves are simple to bipinnately compound, basal and cauline both (rarely only one or the other), and are arranged oppositely or alternately along the stem. They can be simple, but most are usually bipinnately divided. Secondary venation is typically palmate, and there are no stipules. Lamina margins may be smooth, toothed, or lobed.
Flowers of the Hydrophyllaceae Family
Flowers are bisexual and are arranged in terminal or axillary thyrsoidal, usually helicoid or scorpioid cymes that are sometimes congested. There are generally no bracts or bracteoles.
Flowers are usually 5(4)-merous. The calyx is fused at the base or nearly to the tip, with usually 5 lobes, linear to cordate, with valvate aestivation, and is generally persistent and enlarging in fruit.
The corolla also typically has 5 lobes, is rotate to cylindric, is generally deciduous, and often has paired appendages in the tube between the filaments. The corolla is also fused into a tube with lobes, often blue or blue-violet to purple but can also be white, pink, or yellow; corolla scales are present, small, or absent, and aestivation is contorted or imbricate.
Androecium of the Hydrophyllaceae Family
There are typically 5 stamens of equal or unequal length, with filaments that are often expanded and/or lobed at the base, often with scaly appendages, and they are typically epipetalous (adnate to the corolla tube).
Gynoecium of the Hydrophyllaceae Family
The Hydrophyllaceae gynoecium usually comprises a superior ovary, 1-2 carpels, with 2 swollen placentas with axile or (stalked) parietal placentation; usually placentation is intrusive parietal. Sometimes the ovary may appear 2-5-chambered via the intrusive, swollen placenta, but it does not appear lobed or only shallowly so. A nectar disc is often present at the ovary base, but it is sometimes reduced to glands. There is 1 terminal style, usually divided about halfway with punctate, capitate, or capitate-funneliform stigmas. There are 2 to many ovules that are epi-/apo-/pleurotropous, with integuments ca. 6 (-12) cells across.
Fruit of the Hydrophyllaceae Family
The fruit is always a dry membraneous capsule; it may be septicidal or loculicidal, generally with 2 valves, 1 to many seeds. Part of the persistent calyx is adnate to the fruit. Seeds ruminate by the inpushing of the exotestal cells/endothelium; exotestal cells are thickened on inner and radial walls; endotestal cells are persistent. The endosperm is variously copious to scanty.
Taxonomy of Hydrophyllaceae
There are about 320 species in 12 (16) genera in the Hydrophyllaceae family in the Boraginales order of the core eudicots (dicots). This family has been treated as distinct from Boraginaceae and then as the Hydrophylloideae subfamily of it. However, a 2016 revision based on modern phylogenetics has confirmed its status as a distinct family, including the removal of the Namaeae as its own family, the Namaeceae. For more information, check out Luebert et al. (2016) in the references for a great explanation and justification of the split.
The Hydrophyllaceae had been included as a subfamily of Boraginaceae before, though it has recently been made a separate family again. They have very similar-looking scorpioid inflorescences in similar blue-to-violet colors. However, their fruits differ because Hydrophyllaceae always produce a dry, dehiscent capsule, while the Boraginaceae mostly produce indehiscent nutlets, and the Boraginaceae typically have a deeply 4-lobed ovary with a gynobasic style, while the Hydrophyllaceae have a mostly unlobed ovary with a terminal style with 1-2 stigmatic branches.
The Heliotropiaceae has also recently been split out of the Boraginaceae, and it too has scorpioid cymes. However, it can be distinguished from the Hydrophyllaceae by its terminal style with a unique cone-shaped stigmatic head and basal ring-shaped stigma that may be sterile at the tip (the stigma is not terminal) and fruits that are mostly fleshy drupes with 4 stones or are dry schizocarps.
The Namaeceae was, until recently, included as a tribe when the Hydrophyllaceae was the Hydrophylloideae subfamily in the Boraginaceae, but it too has now received family status. This small family is mostly shrubs or small trees (with the exception of Nama which is herbaceous), and they have only simple, cauline leaves, not basal. They also have 2 stylodia, or their style is united for 3/4 of its length with two stigmatic branches.
The Ehretiaceae and Cordiaceae are also recent splits from the Boraginaceae, but these families are both mostly shrubs and trees instead of herbs, and both mostly produce fleshy drupes for their fruits instead of dry capsules.
Distribution of Hydrophyllaceae
The Hydrophyllaceae are a family primarily located in western North America and western South America, from Arctic Alaska south through to southern Patagonia. They are especially common in drier areas of southwestern North America. While less common, they can also be found in eastern North America, but not eastern South America. The Hydrophyllaceae are not naturally found outside of the Americas but the Phacelia have been introduced to parts of Europe and Asia.
Distribution of Hydrophyllaceae in the Americas
Canadian Genera Include:
Ellisia monospecific NAM endemic native from BC east to ON; Hesperochiron 1 W NAM endemic sp. native to BC; Hydrophyllum 5 NAM endemics native to S Canada excluding SK and the maritime provinces; Nemophila 3 former NAM endemics native to BC and AB; Phacelia 13 spp. native to most of Canada except NU, QC, and the maritime provinces; Romanzoffia 2 W NAM endemics native to BC and AB.
USA Genera Include:
Draperia monospecific endemic of CA; Ellisia monospecific NAM endemic, and native to most of the central and eastern USA; Emmenanthe monospecific NAM endemic native CA, NV, UT, and AZ; Eucrypta 2 S NAM endemic spp. native to CA, NV, UT, AZ, NM, and TX; Hesperochiron 1 W NAM endemic sp. native to the western half of the US, E to MN, CO, and AZ; Howellanthus monospecific NAM endemic native to CA (Syn. of Phacelia?); Hydrophyllum 10 NAM endemics native to all of the continental states except for ME, TX, and FL; Nemophila 11 former NAM endemics native to most of the W USA and the SE USA; Phacelia 172 spp. native to all of the USA except FL; Pholistoma 3 S NAM endemics native to OR, CA, NV, and AZ; Romanzoffia 5 NAM endemics native to WA, ID, MT, OR, and CA; Tricardia monspecific USA endemic of CA, NV, UT, and AZ.
Mexico Genera Include:
Emmenanthe monospecific NAM endemic native to NW Mexico; Eucrypta2 S NAM endemic spp. native to NW Mexico; Hesperochiron1 W NAM endemic sp. native to NW Mexico; Nemophila 1? sp. NAM endemics native to NW Mexico; Phacelia many, ~100?? spp. native throughout Mexico; Pholistoma 3 S NAM endemic spp. native to NW Mexico.
Neotropical Genera Include:
Phacelia ~9 spp. native to Guatemala, Argentina, Bolivia, Peru, Uruguay, and Chile.
Patagonia Genera Include:
Phacelia ~5-7 spp. native throughout the Patagonia region.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, along with my own personal observations throughout North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
FNA (1993+). Flora of North America. https://floranorthamerica.org/Main_Page. Accessed 2022-current.
Luebert, F., Cecchi, L., Frohlich, M. W., Gottschling, M., Guilliams, C. M., Hasenstab-Lehman, K. E., Hilger, H. H., Miller, J. S., Mittelbach, M., Nazaire, M., Nepi, M., Nocentini, D., Ober, D., Olmstead, R. G., Selvi, F., Simpson, M. G., Sutorý, K., Valdés, B., Walden, G. K., & Weigend, M. (2016). Familial Classification of the Boraginales. axon, 65(3), 502–522. https://plants.sdsu.edu/amsinckiinae/pdfs/Luebert_etal2016-Boraginales.pdf.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019+). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; Accessed 2020-present.
Walden, Genevieve K., Robert W. Patterson & Richard R. Halse. (2023), Hydrophyllaceae, in Jepson Flora Project (eds.) Jepson eFlora, Revision 12, https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=157, accessed on April 25, 2026.
Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
26 Apr, 2026
25 Apr, 2026
How to Identify the Ehretiaceae Family
Tiquilia canescens aka Shrubby Tiquilia, a native Ehretiaceae of North America. Page Last Updated April 26, 2026
Introduction to the Ehretiaceae Family
The Ehretiaceae are a small family that was only somewhat recently (2016) pulled out of the closely related Boraginaceae family. I only discovered this somewhat recently since so many sources still refer to it as a subfamily of the Borage Family instead. This guide explains how to identify the Ehretiaceae family and how they differ from the new, narrower definition of the Boraginaceae.
My only experience with this mostly tropical family is with Tiquilia, which is a lovely, low-growing herb that is relatively common in the dry soils of the American Southwest. It has pretty, almost succulent leaves, and I always thought it would make a nice ground cover in a xeriscape. However, this means that all of my photos are of that genus. For people living in North America, this is by far the most common member of this family that you will see, although there are other shrubby, small tree, and parasitic species, especially once you get into Mexico. I will add more as I find them!
Common Botanical Description of the Ehretiaceae Family
If you’re new to plant morphology, this guide is a perfect beginner’s description for learning to identify the Ehretiaceae family without needing to know any scientific jargon. Below this section is additional information on uses and morphology, followed by pictures of individual species found in North America. But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Descriptionbelow the images for highly detailed scientific descriptions and genus-level distribution data.
Leaves and Stemsof the Ehretiaceae: This family is mostly woody shrubs or trees, often with fibrous bark and whitish twigs, but perennial herbs and parasitic plants that don’t use chlorophyll are also seen. Leaves are simple (not compound) and arranged alternately along the stem on stalks, although sometimes they are reduced to tiny scales. Margins may be smooth or sometimes with rounded teeth.
Flowersof the Ehretiaceae: Flowers usually have both male (stamens) and female (ovary, stigma, and style) parts in the same flower (bisexual), but occasionally separate male and female flowers are seen on separate male and female plants (called dioecious). Flowers and sepals are usually fused at the base with 5 lobes.
Reproductive Featuresof the Ehretiaceae: There are typically 5 stamens that often stick out past the throat of the flower tube and are sometimes attached to the petals. The ovary is usually surrounded by a nectary disk, and it has a style on top that is typically divided into 2 branches.
Fruitsof the Ehretiaceae: Fruits are mostly drupes (think of a cherry with their stony pits) with 1-2-seeded stones or 4 nutlets.
Uses of Ehretiaceae
The Ehretiaceae, especially the Ehretia genus, are widely used for medicine (pain, fever, and dysentery), timber and furniture, and their edible drupes, especially in Asia, Africa, and parts of the Americas. They are used for treating ailments like fever, dysentery, and pain, with wood for furniture and edible fruits.
Morphology of Ehretiaceae in North America
As I currently only have the herbaceous-looking Tiquilia genus, which is not particularly representative of the family, I will add morphology photos when I acquire more photos.
Some Ehretiaceae Species Found in North America
Tiquilia canescens—Shrubby Tiquilia
The shrubby tiquilia looks a lot more like an herb, but technically you could call it a shrub or sub-shrub because it is woody at the base. It is a short, very low-growing, spreading plant with gray-green, fleshy, egg-shaped leaves that look almost succulent and are often rather congested on its branches. Its 5-lobed tubular flowers are white to pinkish. It is native to the American Southwest in California, Nevada, Arizona, Utah, New Mexico, and Texas and in Northern Mexico in Chihuahua, Sonora, and Baja California.
Tiquilia greggii—Plumed Crinklemat
The plumed crinklemat is another herbaceous-looking low-growing shrub, generally with wider internodes, giving it a more spindly appearance. The leaves are also gray-green and somewhat succulent, but what stands out most are the feathery calyxes that appear in rounded masses with usually only 1-2 flowers blooming at a time. The feathery calyx apparently persists and assists in dispersing the seeds. This one is more rare, and in the United States it is only found in southern New Mexico and the southwestern corner of Texas, being most common throughout northern and central Mexico instead.
Scientific Botanical Description of the Ehretiaceae
Learn to identify the Ehretiaceae family based on its new narrow definition after being removed from the Boraginaceae.
Habit & Leaf Form of the Ehretiaceae Family
This family is mostly woody shrubs or trees, often with fibrous bark, oxidizing stems, and whitish twigs and rarely with thorns (Rochefortia). Perennial herbs are also seen, especially Tiquilia. The indumentum is variable from hirsute to glabrescent. Also, plants in the Pholismateae tribe are achlorphyllous root parasites with glandular hairs and leaves that are reduced to scales.
Leaves are simple, alternately arranged, petiolate, with margins that are entire to crenate, or occasionally dissected (in Cortesia), and without stipules. In achlorophyllous root parasites, the leaves are typically reduced to scales.
Flowers of the Ehretiaceae Family
Inflorescences are axillary or sometimes terminal, usually laxly cymose or thyrsoidal, sometimes congested, and occasionally in few-flowered corymbs or solitary. In parasitic plants, they are condensed and more or less capitate.
Flowers are mostly bisexual, although occasionally plants are dioecious (Lepidocordia and Rochefortia). Flowers are 5-merous, usually with radial symmetry. The often long, persistent calyx has 5 lobes, fused or may be free to the base; aestivation is quincuncial or sometimes imbricate. The corolla is sympetalous and tubular with 5 spreading lobes; it is usually rotate, campanulate, or urceolate; aestivation is imbricate, and they are white, red, or sometimes blue.
Androecium of the Ehretiaceae Family
There are 5 stamens that are often epipetalous, fused to the floral tube at least at the base, and may be puberulent at the base; anthers are generally exserted.
Gynoecium of the Ehretiaceae Family
The ovary is bicarpellate, 1-4-locular from secondary division, superior, and generally subtended by a disk-like nectary. There is a bifid terminal style with an elongated clavate to capitate stigma. Placentation is apical to axile. There is usually 1 fertile ovule per carpel, apotropous, with integument 6-12 cells across, and epidermal cells anticlinally elongated or not. Parasitic members may have 10 or more ovules.
Fruit of the Ehretiaceae Family
Fruits are drupes, often surrounded by a persistent, accrescent calyx. They often dry and separate into 2 2-seeded pyrenes, 4 1-seeded pyrenes or schizocarps, or 4 nutlets. Seeds often have copious endosperm, but some seeds have none.
Taxonomy of Ehretiaceae
There are about 155 species in 10(7) genera in the Ehretiaceae family in the Boraginales order of the core eudicots (dicots). The Ehretiaceae family has frequently been treated as a subfamily of the Boraginaceae. A 2016 revision by the Boraginales Working Group, however, confirmed its status as a distinct family, and this is what is also listed on the Angiosperm Phylogeny Group, which I use as my most current authoritative source. This definition of the Ehretiaceae includes the Lennoaceae nested within it.
The Ehretiaceae was recently split from the Boraginaceae, but the Boraginaceae can be distinguished by usually being herbs and virtually always having a gynobasic style rather than a terminal one in the Ehretiaceae.
The Cordiaceae was also recently split from the Boraginaceae, and it too is mostly woody trees and shrubs with fleshy drupes, but they have characteristic 4-lobed rather than bifid stigmas; if they do have 2 stigmatic branches, then the fruit is enclosed in an accrescent calyx.
The Heliotropiaceae has also recently been split out of the Boraginaceae family, but it’s a family of more herbs or subshrubs. However, it does have some trees that also produce drupes and could be confused. But, it can usually be distinguished by its often deeply lobed ovary and unique cone-shaped stigma.
Distribution of Ehretiaceae
The Ehretiaceae are a mostly tropical and subtropical family throughout the tropics, though noticeably absent from eastern South America. There is also a strong presence of this family in the arid American Southwest.
Distribution of Ehretiaceae in the Americas
Canadian Genera Include:
Absent.
USA Genera Include:
Bourreria 3 spp. native to FL; Ehretia 1sp. native in TX; Pholisma 2 S NAM endemic spp. native in CA and AZ; Tiquilia 9 spp. native in all of W half of the USA, except for MT, also in MO.
Mexico Genera Include:
Bourreria 16 spp. native to all of Mexico; Ehretia 4 spp. native to all of Mexico; Lennoa monospecific endemic to Mexico and the N neotropics; Lepidocordia 1 N neoendemic sp. native to SW and SE Mexico; Pholisma 3 S NAM endemic spp. native to northern Mexico; Rochefortia 1 sp. native to much of Mexico except NW and C; Tiquilia ~12 spp native throughout all of Mexico.
Neotropical Genera Include:
Bourreria ~30? spp. native CAM, Antilles, Colombia, Venezuela, Ecuador; Ehretia ~3 spp. native in CAM, Antilles, N+E Brazil, and N Argentina; Keraunea 5 spp. endemic to eastern Brazil; Lennoa monospecific endemic of Mexico, CAM, Colombia, and Venezuela; Lepidocordia 2 N neoendemic spp. native to Mexico, El Salvador, Honduras, Nicaragua, Venezuela, Guyana, and N Brazil; Rochefortia 9 neoendemic spp. native to Guatemala, Belize, Honduras, Nicaragua, Costa Rica, Antilles, Colombia, Venezuela, and Peru; Tiquilia ~20 spp. native to Ecuador, Peru, Bolivia, N Chile, and NW+S Argentina, including 4? narrow endemics of the Galapagos.
Patagonia Genera Include:
Tiquilia 1? sp. native to S Argentina.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, along with my own personal observations throughout North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
FNA (1993+). Flora of North America. https://floranorthamerica.org/Main_Page. Accessed 2022-current.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019+). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
Michael G. Simpson 2021, Ehretiaceae, in Jepson Flora Project (eds.) Jepson eFlora, Revision 9, https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=84713, accessed on April 24, 2026.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
25 Apr, 2026
23 Apr, 2026
How to Identify the Boraginaceae Family
Anchusa officinalis inflorescence with violet blue flowers. Learn to identify the Boraginaceae family! Page Last Updated May 15, 2026.
Introduction to the Boraginaceae Family
The Boraginaceae family has undergone major revisions over the years, including several small families and then more recently, having them removed. This description teaches how to identify the Boraginaceae based on the currently accepted, much narrower definition of the family that excludes Heliotropiaceae, Hydrophyllaceae, and others, which I will all cover separately.
What I love about this family is their often instantly blue-to-violet flowers almost always arranged in unique clusters called “scorpioid cymes.” They are truly beautiful; I even love their coarse hairs that can cause rashes in some people, but to me, it just makes them even more beautiful. But I might be biased too, since I think all flowers are beautiful in their own way.
Common Botanical Description of the Boraginaceae Family
If you’re new to plant morphology, this common botanical description is a perfect beginner’s description for learning to identify the Boraginaceae family, with no need to know any scientific jargon not explained in the description. Below this section is additional information on uses and morphology photos to help you identify the family, followed by pictures of individual species found in North America. But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Descriptionbelow the images for highly detailed scientific descriptions, taxonomic information, and genus-level distribution data in North, Central, and South America.
Leaves and Stemsof the Boraginaceae: Most members are herbaceous plants, with occasional woody shrubs, trees, or vines, often accompanied by characteristic coarse hairs that can cause skin reactions. The leaves vary in size but are always simple (not compound) and are usually arranged alternately along the stem; however, in rare cases, the lower leaves may be in opposite pairs. Leaves are usually thin to lance-shaped, and most have entire margins, but in rare cases they may be toothed. Another characteristic feature of the family is that the leaves never have small leaf-like appendages called stipules at their base, often seen in other families.
Flowersof the Boraginaceae: The flowers of this family are mostly bisexual, containing both male (stamens) and female (ovary, style, stigma) parts in the same flower. What is most characteristic of this and closely related families is the flowers in coiled clusters called “scorpioid cymes.” Boraginaceae flowers are usually regular, meaning they can be divided in half on multiple planes of symmetry, and contain usually 5 sepals that may be free or joined at the base into a tube and are often covered with hairs. They also have 5 petals that are usually blue or purple (but may be pink, yellow, or white) and often have a collection of scales in the throat.
Reproductive Featuresof the Boraginaceae: The stamens can vary, being free or joined, but there are always five fertile stamens (with pollen-producing anthers), and they are always attached in the throat of the flower. The ovary is deeply four-lobed, and there is a single style attached at its base.
Fruitsof the Boraginaceae: The fruits are always non-fleshy nutlets or sometimes dry, dehiscent fruits called schizocarps that split apart when mature.
Uses of Boraginaceae
Many members of the family are used ornamentally for their lovely flowers, while others are used medicinally, and still others are used as a natural source of dye.
Common cultivated family members include forget-me-not (Myosotis), Symphytum, Borago, and more. Many species have been introduced as ornamental plants or weeds, e.g., the genera Anchusa, Borago, Cynoglossum, Echium, Myosotis, and Symphytum.
Morphology of Boraginaceae in North America
Learn to identify the Boraginaceae family with morphology photos
Some Boraginaceae Species Found in North America
Boraginoideae Subfamily
Anchusa officinalis—Common Alkanet
This beautiful introduced wildflower has long, lance-shaped leaves that become smaller on shorter petioles further up the stem. Most of the plant is covered in fine, stiff hairs, and it produces deep violet-blue flowers with five spreading, rounded lobes. It is native primarily to the Mediterranean region, but also to most of Europe and western Asia. It is now an occasional introduced weed in North America, like this one growing wild not far from human settlements in Peachland, British Columbia, Canada.
Buglossoides arvensis—Corn Gromwell
An annual herb up to 40 cm long with stems that branch from the base, producing terminal racemes of pale blue to white flowers with forward-facing hairs on the outside and narrowly lance-shaped leaves that typically have a central groove on the upper surface. Native throughout Eurasia and northern Africa but widely introduced in Canada and the United States, as well as southern South America. This one was found in a well-maintained park in Vernon, British Columbia, Canada.
Lithospermum ruderale—Wayside Gromwell
Unlike most members of the Boraginoideae subfamily, this perennial herb is native to North America, endemic to western North America from British Columbia east to Saskatchewan in Canada and from Washington State south to California and east to Montana south to Colorado in the United States. It also produces narrowly lance-shaped leaves with fine, coarse hairs and light yellow tubular flowers. It is common in dry soil with good drainage in sunny locations in its range. This one was in Princeton, British Columbia.
Cynoglossoideae Subfamily
Andersonglossum virginianum—Southern Wild Comfrey
This pretty wildflower has large comfrey-like leaves that give it one of its common names. The leaves are slightly hairy and tend to clasp the hairy stem at their base. It produces pale bluish flowers on erect, branching stems that often turn a violet color as they age. This is an uncommon endemic native of the eastern United States from Texas east to Florida and north to Vermont, where it normally grows in forested areas.
Cryptantha crassisepala—Thick-Sepaled Cryptanth
This very hairy annual herb only grows up to about 15 cm tall, with 2-6 cm long leaves and small white flowers with very thick and hairy sepals. However, examination of fruits is often needed for a positive ID. It is a southern North American endemic from California east to Kansas and Texas as well as throughout northern Mexico. It tends to grow in arid and semi-arid locations; this one was on a roadside in New Mexico.
Oreocarya aka Cryptantha flava—Yellow Cryptantha
Most sources still refer to Oreocarya as a separate genus, but authoritative sources like APG and USDA now consider it a synonym for Cryptantha, so we use both names here. This narrow endemic of Colorado, Wyoming, Arizona, Utah, and New Mexico in the United States is known for its cheerful yellow flowers and thinner but still very hairy sepals. This one was in the Wilson Arch area, Utah.
Another lovely Cryptantha endemic to the American Southwest, this time in Nevada, Utah, Colorado, Arizona, and New Mexico. It has white tubular flowers with conspicuous yellow appendages in their throats and the hairy sepals we are used to seeing in the genus. This one was found growing on a dry roadside outside of Cuba, New Mexico.
Myosotis arvsenis—Field Forget-Me-Not
An annual or short-lived perennial herb with stalkless, hairy leaves and pretty inflorescences of blue flowers with white to yellow throat appendages. The flowers are in typical scorpioid cymes, but they are best visualized while the flowers are still in bud as they elongate and straighten as they bloom. This species is originally native to northern Eurasia but is now widely introduced to northern North America. This was on the side of a logging road near Sechelt, British Columbia, Canada.
Myosotis macrosperma—Largeseed Forget-Me-Not
An annual herb with hairy, stalkless leaves with a prominent midrib and tiny white flowers in condensed cymes with hairy sepals and green bracts. This one is a North American native found in disturbed areas throughout the southeastern United States north into southern Ontario, Canada.
Lappula occidentalis—Western Stickseed
This hairy annual has stalked basal leaves that are mostly oblong with rounded tips and narrower, stalkless stem leaves with pointed tips. They are best known for their elongated inflorescences of tiny white to pale blue flowers, followed by fruits containing four nutlets, each with a row of slender prickles. It is native throughout western North America from Alaska south to northern Mexico and east to Manitoba, Canada, and Iowa, United States, with some disjunct populations in the eastern United States.
Scientific Botanical Description of the Boraginaceae
Learn to identify the Boraginaceae family based on the newer, more narrow definition of the family.
Habit & Leaf Form of the Boraginaceae Family
Most are annual or perennial herbaceous plants from taproots with occasional woody shrubs, trees, or self-supporting (usually) vines. They are often hispid or scabrid with coarse hairs that may contain SiO₂ or CaCO₃, which can cause adverse skin reactions in sensitive individuals. They may or may not have a basal aggregation of leaves. Helophytic, mesophytic, or xerophytic.
Leaves are minute to medium-sized, usually alternate or sometimes alternate and opposite below. They are simple, flat, herbaceous, petiolate to sessile, usually non-sheathing or sometimes sheathing in basal rosettes, not gland-dotted, and epulvinate. The lamina is entire, usually narrow, linear to lanceolate. Leaves lack stipules. Lamina margins are mostly entire, rarely crenate or dentate. Domatia may be present.
Flowers of the Boraginaceae Family
Plants are usually hermaphrodites or occasionally gynodioecious (Echium), with predominantly entomophilous pollination via Hymenoptera. Flowers are usually aggregated in coiled (scorpioid) cymes that may appear doubled in some species; coiled cymes typically elongate in fruit. Rarely are flowers solitary. Inflorescences are terminal or axillary.
Flowers are bracteate or not, usually regular or irregular and somewhat zygomorphic (e.g. Echium); usually 5-merous and tetracyclic. Free hypanthium is not present. Hypogynous disk present or absent. Perianth has a distinct calyx and corolla with 10 (11–13) parts in 2 whorls; mostly isomerous or sometimes anisomerous (Plagiobothrys).
Calyx 5 (usually) or 5–8 (sometimes Plagiobothrys) in 1 whorl; they may be free or connate basally with lobes shorter to longer than the tube; the degree of gamosepaly is 0.1–0.5; often covered with trichomes. Calyx persistent; imbricate, open in bud or valvate (rarely).
Corolla 5 parts in 1 whorl, often appendiculate with a corona of scales from the throat protecting the nectar. Petals are fused into a tube with lobes shorter to longer than the tube. Corolla is imbricate or contorted; rotate, campanulate to hypocrateriform or tubular; unequal, regular, or often bilabiate in Echium. They are often blue or purple in color but may also be pink, white, or yellow.
Androecium of the Boraginaceae Family
There are 5 unbranched androecial members made of exclusively fertile stamens that are adnate midway down or in the throat of the corolla tube; all are equal or unequal, free or coherent, and 1-whorled. Stamens are not didynamous or tetradynamous; they are isomerous with the perianth, arranged opposite the sepals, with filaments, or sometimes appearing sessile, inserted or exserted. Filaments are appendiculate or not. Anthers are cohering, free, or connivent; dorsifixed to basifixed; dehiscing via longitudinal slits; introrse; tetrasporangiate; appendaged or unappendaged.
Gynoecium of the Boraginaceae Family
The gynoecium is usually 2-carpeled or 4–5 carpeled (some Trigonotis). Pistil 2- or 4-celled (usually via false septa) or 8-10-celled (via false septa in some Trigonotis). The gynoecium is syncarpous with a superior ovary that is nearly always 2 locular but often appears 4 locular via false septa. The gynoecium is median. Style 1 is always gynobasic from an often deeply 4-lobed ovary. Stigmas 1–2: when simple, they are often 2-lobed but may also be capitate or minute; nearly always dry type; papillate. Placentation is basal. The ovules are 2 per locule, usually separating into 1-ovuled portions; they are positioned horizontally to ascending, epitropous, and have a dorsal raphe.
Fruit of the Boraginaceae Family
The fruits are primarily non-fleshy nutlets, dehiscent, indehiscent, or a schizocarp with 4 or 8–10 (sometimes Trigonotis) mericarps.
Taxonomy of Boraginaceae
There are 1,793 species in 94 genera in the Boraginaceae family in the Boraginales order of the core eudicots (dicots). This family recently underwent major revisions, including the removal of the Hydrophyllaceae, Heliotropiaceae, Cordiaceae, Ehretiaceae, and others based on modern molecular phylogenetics. As a result, many genera have changed in the family, but the genera listed immediately below are accurate as per APG IV. For more information on the justification of this split of the Boraginales, I encourage you to check out Luebert et al. (2016) in the references below.
There are 3 currently accepted subfamilies:
Boraginoideae is a large subfamily concentrated in the Mediterranean region, with some also in East Asia, Africa, and South America, but it is also introduced elsewhere. They are mostly perennial herbs, some annuals, and some shrubs; their flowers typically have a single line of symmetry and basal scales, the gynobase is flat, and the nutlets have a basal attachment scar.
Cynoglossoideae is the largest subfamily with a nearly cosmopolitan distribution. It is a group of mostly herbs (annual to perennial) with some shrubs, leaves with obvious secondary venation, bractless flowers, a broadly pyramidal to flat gynobase, and often compressed nutlets that are ventrally attached with a large triangular scar.
Echinochiloideae is a small subfamily with only 3 genera located in Mexico, south to northeastern Argentina, plus the Canary Islands, Africa, and east to western India. They are characterized by having densely hairy corolla throats and punctate stigmas (subterminal, sterile tips, bilobed or notched) with fruits that are laterally compressed nutlets.
The Hydrophyllaceae had been included as a subfamily of Boraginaceae before, though it has recently been removed and made a separate family again. They have very similar-looking scorpioid inflorescences in similar blue-to-violet colors. However, the Hydrophyllaceae always have dry capsule fruits, while the Boraginaceae have nutlets. The ovaries and seeds also differ.
The Heliotropiaceae has also recently been split out of the family, and it too has scorpioid cymes, though not all members do. However, it can be distinguished by having fewer bristly hairs that are always eglandular, leaves that are usually conduplicate, an ovary that is still often deeply lobed but has a cone-shaped stigma, and fruits that are drupes with 4 stones or are dry schizocarps.
The Ehretiaceae is another recent split. It is a small family with only 7 genera of mostly shrubs and trees as opposed to mostly herbs, and while the Boraginaceae have a gynobasic style, most of this family (excluding Tiquilia) has a terminal style with a bifid stigma.
The Cordiaceae is another recent split, but these are also mostly trees and shrubs with characteristic 4-lobed stigmas and fleshy drupes as opposed to mostly herbs with 2-lobed stigmas and producing nutlets in the Boraginaceae.
Distribution of Boraginaceae
The Boraginaceae are a cosmopolitan family found around the tropics, warm and cool temperate, and even arctic climates, although they are predominantly found in warm temperate climates, with a strong Mediterranean concentration. In the Americas, the family is found in Canada, the USA, Mexico, Central America, and South America.
Distribution of Boraginaceae in the Americas
Canadian Genera Include:
Boraginoideae: Anchusa 3 spp. intro to all S provinces except NL; Borago 1 sp. intro to all S provinces but ephemeral in ON, QC, NS, and NL; Buglossoides 1 sp. intro to BC, MB, ON, QC, and NS; Cerinthe 1 sp. intro to QC?; Echium 2 spp. Intro to all of S Canada except Labrador; Lithospermum 8 spp. native to BC, AB, SK, MB, ON, and QC and intro NB; Nonea 2 spp. intro to AB and QC; Pulmonaria 2 spp. intro to ON, QC, and NS; Pentaglottis 1 sp. intro to BC; Symphytum 3 spp. introduced in all of S Canada except Labrador. Cynoglossoideae: Adelinia monospecific W NAM endemic native BC; Amsinckia 6 spp. native to BC and introduced to YT, AB, and SK; Andersonglossum 1 NAM endemic sp. native to all S provinces exc. Labrador, also in YT; Asperugo monospecific intro BC, AB, SK, and MB (and Greenland); Cryptantha 11 spp. native to BC, AB, and SK; Cynoglossum 1 sp. intro to all of S Canada exc. NL and PE; Eritrichium 6 spp. native to YT and NT; Hackelia 6 spp. native to all of Canada except NU, NS, PE, and NL; Lappula 2 spp. native to YT, NT, BC, AB, SK, MB, and introduced to ON, QC, NS, NB, PE, and NL; Mertensia 7 spp. native to all of Canada, including the Arctic (and Greenland); Myosotis 9 spp. native to BC, AB, YT, NT, ON, QC, NB, NS, PE, and NL and intro to SK and MB (and Greenland); Omphalodes 2 spp. intro in BC, ON, and QC; Oreocarya (or ~ Cryptantha) 1 NAM endemic native to BC, AB, and SK; Pectocarya 1 sp. native to BC; Plagiobothrys 5 spp. native to BC, AB, SK, and MB, and intro to YT, ON, QC, and NB.
USA Genera Include:
Boraginoideae: Anchusa 5 spp. intro much of USA exc. NV, AZ, NM, NE, KS, OK, MO, AR, LA, MS, AL, GA, FL, SC, IN, WV, and VT; Borago 1 sp. intro to WA, OR, CA, UT, MT, ND, MI, IL, MN, WI, TN, OH, VA, WV, MD, PA, NJ, NY, CT, RI, MA, VT, NH, and ME; Brunnera 1 sp. intro to MO, OH, and NY; Buglossoides 1 sp. intro to most of the USA, excluding NV, AZ, and NM; Echium 7 spp. intro to most of USA, including AK but excluding NV, AZ, ND, MS, AL, and FL; Lithospermum 17-21 spp. native and intro to all of the USA; Nonea 3 spp. intro to TN, PA, NY, and ME; Pulmonaria 1 sp. intro to NY, VT. Cynoglossoideae: Adelinia monospecific W NAM endemic native to WA, OR, and CA; Amsinckia 10 spp. native to W USA MT S to NM and all W, and intro to ND, NE, OK, TX, WI, IL, MS, OH, PA, NY, CT, MA, NH, ME, VA, NC, SC, AK, and HI; Andersonglossum 3 NAM endemic spp. native, inc. 1 endemic to OR and CA, 1 endemic to E USA from MN S to LA, plus ND, SD, OK, and TX, with a 3rd spp. native to SD, IA, WI, IL, IN, NJ, NY, NH, ME, and Canada; Asperugo monospecific intro to CA, CO, and IL; Bothriospermum 1 sp. intro HI; Cryptantha 82 spp. native in W USA from ND S to TX and all W, inc. MA, native and intro AK, most of which are endemic; Cynoglossum 9 spp. intro and native to the entire USA and intro to HI; Dasynotus monospecific narrow endemic of ID; Eritrichium 3 spp. native to AK, WA, OR, ID, WY, MT, CO, UT, and NM; Eremocarya 2 spp. S NAM endemic native OR, CA, NV, UT, AZ, NM, TX; Greeneocharis 2 spp. native to WA, OR, CA (1 endemic), ID, NV, AZ, UT, and CO; Hackelia 29 spp. native to almost all of the USA except FL, including AK; Harpagonella 1 S NAM endemic native to CA and AZ; Johnstonella ? spp. native to CA, NV, UT, AZ, NM, and TX; Lappula 4 spp. native and intro most of the USA, including AK, but excluding LA, MS, AL, FL, GA, and VA; Mertensia 18 spp. native to most of the USA, including AK, but exc. TX, OK, LA, and FL; Mimophytum 1 S NAM endemic sp. native to TX; Myosotis 11 spp. native and intro most of the USA, inc. AK, exc. ND, and intro in HI; Omphalodes 2 spp. native and intro OR and TX (USDA, POWO says otherwise); Oreocarya (or ~ Cryptantha) 32 NAM endemics native W USA from ND S to TX and all states W; Pectocarya 8 spp. native to WA, OR, ID, WY, CA, NV, UT, AZ, NM, and TX; Plagiobothrys 43 spp. native to WA, OR, CA (12+ endemics), ID, MT, WY, CO, NV, UT, AZ, NM, ND, SD, NE, WI, MI, IL, AR, LA, NC, PA, MA, and ME, and intro and native to AK; Symphytum 3 spp. introduced in WA, OR, CA, ID, MT, WY, UT, CO, NM, MI, WI, MN, MO, AR, TN, KY, GA, NC, VA, WV, IN, OH, PA, MD, DE, NJ, NY, CT, RI, MA, VT, NH, ME, and AK. Echinochiloideae: Antiphytum 2 spp. native to NM and TX.
Mexico Genera Include:
Boraginoideae: Lithospermum ~43 spp. native to all of Mexico, including ~32 endemics. Cynoglossoideae: Amsinckia 3 spp. native to N Mexico; Borago 1 sp. intro to SW+C Mexico; Cryptantha 5-6 spp. native to N Mexico, including 3+ endemics; Cynoglossum 1 sp. intro to NE+SW Mexico; Eremocarya 2 S NAM endemic spp. native to NW Mexico; Hackelia 5 spp. native to all of Mexico (1 endemic); Greeneocharis 1 sp. native to NW Mexico; Harpagonella 2 S NAM endemic spp. native to BC, BCS, Guadalupe Is., and Son; Johnstonella 17 spp. native to most of Mexico except Chp, Tab, Cam, Yuc, and QR, most are endemic to Mexico; Lappula 1-2 spp. native to N Mexico; Mertensia 1 sp. native to NE Mexico; Mimophytum 11 S NAM endemic spp. native to Coa, NL, Tam, Dgo, SLP, Pue, Qro, Hgo, Gto, Mex, Tlx, Ver, NE, C Mexico, Ver, including 10 endemics; Oncaglossum monospecific endemic in NE, C, and SW Mexico; Oreocarya 3-4? spp NAM endemics native throughout the N half of Mexico; Pectocarya 6 spp. native to NW Mexico, including 1-2 endemics of BC; Plagiobothrys 7+ spp. native to NW+C Mexico. Echinochiloideae: Amphibologyne monospecific endemic of NE and SW Mexico; Antiphytum ~10+ spp. native to much of Mexico exc. Chp, Cam, Tab, Yuc, QR, including several endemics.
Neotropical Genera Include:
Boraginoideae: Anchusa 1 sp. intro to Argentina; Borago 1 sp. intro to Guatemala, Honduras, Greater Antilles, Colombia, Ecuador, Peru, C Chile, Uruguay, and Argentina; Buglossoides 1 sp. intro to Bolivia, Argentina, and Uruguay; Echium 1 sp. intro to C Chile, Argentina, Uruguay, and S Brazil; Lithospermum ~7 spp. native to Guatemala (1) and the rest are endemic to the Andes of Colombia, Venezuela, Ecuador, Peru, and Bolivia; Moritzia 3 neoendemic spp. native to Costa Rica, Panama, Colombia, Venezuela, Ecuador, Peru, and SE+S Brazil; Symphytum 1 sp. intro to Dominican Republic, Haiti, C Brazil, and NE Argentina; Thaumatocaryon 2 E SAM endemic spp. native to S+SE Brazil, Paraguay, and NE Argentina. Cynoglossoideae: Amsinckia 2-3 spp. originally endemic to W SAM in Ecuador (1 still endemic), Peru, Bolivia, Chile, and Argentina; Cryptantha ~50 spp. native and endemic to W SAM in Peru, Bolivia, N+C Chile, and Argentina; Cynoglossum 1 sp. intro Jamaica, Haiti, Dominican Republic; Guatemala, Honduras, Costa Rica, Panama, Colombia, Venezuela, Ecuador, Peru, Bolivia, SE Brazil, Argentina, C+S Chile, and Juan Fernandez Is.; Greeneocharis 1 sp. native NW+S Argentina; Hackelia 7 spp. native to Guatemala, Honduras, Costa Rica, Panama, Colombia, Venezuela, Ecuador, Peru (1 endemic), Bolivia, and N Argentina; Iberodes 1 sp. intro to C Chile; Johnstonella ~6 spp. native to Peru, N Chile, and NW Argentina; Lappula 1-3 spp. intro to Venezuela and native N+S Argentina; Myosotis 1-2 spp. intro to Guatemala, Dominican Republic, Haiti, Colombia, Ecuador, Peru, Bolivia, N+C Chile, N Argentina, SE Brazil, Uruguay, and Trinidad-Tobago; Nesocaryum monospecific endemic of the Desventurados Islands off the coast of NC Chile; Pectocarya 6 spp. native to Ecuador, Peru, Bolivia, N+C Chile, and Argentina; Plagiobothrys 8+ spp. native to Colombia, Ecuador, Peru, Bolivia, C+S Chile, and NW+S Argentina; Selkirkia 4 SAM endemics, inc. 1 endemic to Juan Fernandez Is., 2 endemic to C+S Chile, and 1 endemic to Colombia and Ecuador; Trichodesma 1 sp. intro to Windward Is. Echinochiloideae: Antiphytum 2-3 spp. endemic to S Brazil and Uruguay.
Patagonia Genera Include:
Boraginoideae: Anchusa 1 sp. intro to S Argentina; Borago 1 sp. intro to C Chile and S Argentina; Buglossoides 1 sp. intro to S Argentina; Echium 1 sp. intro to Patagonia region; Lithospermum 1 sp. intro S Argentina. Cynoglossoideae: Amsinckia 1-2 spp. native throughout Patagonia; Asperugo monospecific intro to Patagonia region; Cynoglossum 1 sp. intro throughout Patagonia; Greeneocharis 1 sp. native S Argentina; Lappula 1 sp. native to Patagonia region; Myosotis 1-2 spp. native to S Chile and S Argentina and intro to Falkland Is.; Pectocarya 1 sp. native to S Argentina and SC Chile; Plagiobothrys 1 sp. native to C+S Chile and S Argentina; Selkirkia 2 SAM endemics native to SC and S Chile.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, along with my own personal observations throughout North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
FNA (1993+). Flora of North America. https://floranorthamerica.org/Main_Page. Accessed 2022-current.
Luebert, F., Cecchi, L., Frohlich, M. W., Gottschling, M., Guilliams, C. M., Hasenstab-Lehman, K. E., Hilger, H. H., Miller, J. S., Mittelbach, M., Nazaire, M., Nepi, M., Nocentini, D., Ober, D., Olmstead, R. G., Selvi, F., Simpson, M. G., Sutorý, K., Valdés, B., Walden, G. K., & Weigend, M. (2016). Familial Classification of the Boraginales. axon, 65(3), 502–522. https://plants.sdsu.edu/amsinckiinae/pdfs/Luebert_etal2016-Boraginales.pdf.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019+). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
Stevens, P. F. (2001+). Angiosperm Phylogeny Website. Version 14, July 2017 [more or less continuously updated since]. http://www.mobot.org/MOBOT/research/APweb/. This is the authoritative source on currently accepted families, subfamilies, tribes, and genera.
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; Accessed 2020-present.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
23 Apr, 2026
19 Apr, 2026
How to Identify the Campanulaceae or Bellflower Family
Campanula alaskana the Alaskan Bellflower, showing the bell-shaped flower this family is named for Page Last Updated August 28, 2026.
Introduction to the Campanulaceae Family
The Campanulaceae, or Bellflower family, is a widespread family of popular bell-shaped wildflowers that is found on every continent except Antarctica, and it is a popular garden ornamental for its lovely flowers.
The first time I found one was on a grassy bluff next to the ocean, and I automatically knew what family it was in because of the pretty blue bell-shaped flowers with the long style that the family is best known for, although other colors and flower shapes do exist in the family.
Beginner’s Guide to The Bellflower (Campanulaceae) Family
If you’re new to plant morphology, this guide is a perfect beginner’s description, with no need to know any scientific jargon. Below this section is additional information on uses and morphology photos to help you identify the family, followed by pictures of individual species found in North America. But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Descriptionbelow the images for highly detailed scientific descriptions and genus-level distribution data.
Leaves and Stems of the Bellflower Family
Most members are perennial herbs, but some annuals, biennials, shrubs, or small trees exist in the family; mostly they live on land, but some are aquatic. One key identifying feature is the milky juice that is released when they are damaged.
Leaves are usually arranged alternately on the stem but are sometimes in opposite pairs or whorls. They are usually simple (not compound), linear, lance-shaped, oblong, egg-shaped, or rounded with variously toothed margins but are occasionally divided into opposite pairs of leaflets.
Flowers of the Bellflower Family
Flowers are often medium to large and showing, appearing singly or in various spikes or umbrella-shaped clusters. Flowers are typically bell-shaped or star-shaped, giving them the common name of bellflowers. Most are in shades of blue, but they can also be found in white, yellow, red, pink, or purple. Flowers are often symmetrical but can be irregular or “two-lipped,” like in Lobelia.
Reproductive Features of the Bellflower Family
Reproductive features are specialized to ensure successful pollination by insects. There are usually 5 stamens (male parts) that may be separate or joined in a long column surrounding the female parts (ovary, style). Most species have an inferior ovary located below where the petals attach. A single long style comes up through the center of the flower.
Fruits of the Bellflower Family
The fruit is almost always a dry capsule that splits open through valves, irregular slits, or other ways to release the seeds. Very rarely is the fruit a fleshy berry (mostly in the Lobelioideae subfamily). Some seeds are equipped with wings to aid in dispersal.
Morphology of Campanulaceae in North America
Learn how to identify the Campanulaceae family with morphology photos
Some Campanulaceae Species Found in North America
Campanuloideae Subfamily
Campanula alaskana—Alaska Bellflower
Herbaceous perennial from rhizomes with weak stems with larger basal leaves and small, linear stem leaves. Flowers are large and showy, bell-shaped, nodding, and up to 3 cm long in blue-violet to lavender colors. It is often confused with Campanula rotundifolia but has broader leaves, and it is only found along the North Pacific from Washington State north to Alaska.
Campanula petiolata—Western Harebell
This was a recent taxon split from the much more widespread Campanula rotundifolia, with which it shares many characteristics but tends to be more upright with stronger stems. The long style with a 3-lobed tip visible in the photo is common among Campanula rotundifolia and close relatives like these. Some taxonomists do not recognize this or Campanula alaskana as separate species from Campanula rotundifolia.
Campanulastrum americanum—American Bellflower
A tall, erect annual or biennial common in moist woods. Unlike most bellflowers, it has flat star-shaped flowers in elongated spikes, and it has alternate lance-shaped leaves compared to the often linear ones seen in Campanula species.
Triodanis biflora—Venus’s Looking Glass
This species is an annual herb of disturbed areas with alternate leaves that do not wrap around the stem. It has pinkish to purple bellflowers with widely spreading lobes that make them look like a star. Native to the southern and eastern United States, Mexico, and South America.
This species is very similar to Triodanis biflora, with a similar native range, though perhaps a bit more widespread. It can usually be differentiated by the leaves shown here that clasp and nearly wrap all the way around the stem. However, they can hybridize, making identification difficult.
Lobelioideae Subfamily
Lobelia appendiculata—Pale Lobelia
This species is an annual unbranched herb that grows up to 60 cm tall with oblong to egg-shaped leaves that clasp partway around the stem. It has pale blue to white two-lipped flowers (2 upper lobes and 3 larger lower ones) in a loose terminal spike. It is native to the south-central USA.
Lobelia cardinalis—Cardinal Flower
This herbaceous perennial grows up to 1.2 m tall and is found mostly in or near bogs, riverbanks, swamps, or wet forests. It has large, lance-shaped to oval leaves with toothed margins. The flowers are large and bright red, with 5 deeply cut lobes. Plants with pink or white flowers occasionally occur. It is native to southeastern Canada, the eastern and southern USA, and south to northern Colombia.
Lobelia spicata—Pale Spike Lobelia
This short-lived perennial is often found flowering below taller grasses in sunny or semi-shaded prairies, woodlands, and disturbed areas. They have simple, variously elongated-shaped leaves with shallow teeth and are most known for their sometimes densely flowered spikes of white or pale blue flowers, like those in the photo. Native to southern Canada and the eastern USA.
Uses of the Campanulaceae Family
With plenty of showy flowers, this family is popular for garden ornamentals, especially from Lobelia, Wahlenbergia, Codonopsis, Jasione, and more than 120 species of Campanula. They are widely grown in gardens and landscapes around the world.
Ecosystem and Wildlife Values of the Campanulaceae Family
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Taxonomy of Campanulaceae
There are 2,380 species in 84 genera of the Asterales order of the core Eudicots (dicots).
The family is divided into five subfamilies, 2 of which are large and/or very widespread:
Campanuloideae Subfamily
The Campanuloideae is a large subfamily characterized by polysymmetric flowers, stamens that sprawl at the bottom of the corolla tube after the anthers have dehisced, an inferior ovary, and long-hairy styles. These are widespread and found worldwide, with especially high diversity in the north temperate Old World.
The Lobelioideae is a subfamily of herbs or small trees with terminal, occasionally axillary, inflorescences and large to small resupinate flowers. Stamen filaments are connate at least apically, and anthers are connate. They are mostly tropical, especially common in the New World with a major center of diversity in the Andes and over 100 endemic species found on the Hawaiian Islands. They are not present in the Arctic and are absent from the Near East and Central Asia.
The Nemacladoideae is a small subfamily of tiny annuals (rarely perennial) with sub-opposite leaves, racemes without bracteoles, and small flowers that are not resupinate. Anthers are connivent; filaments are connate apically and may be free at the base. These are restricted to the southwestern USA (especially California) and northwestern Mexico.
The Cyphoideae are a monogeneric group of perennial herbs (twining vines) and shrubs with tuberous roots. The fused corolla is split almost to the base into two groups, usually with three upper lobes and two lower lobes. Stamen filaments may be free or connate. It is mostly found in Southern Africa, but also in East Africa and the Cape Verde Islands.
Genera of the Cyphioideae Subfamily
Cyphia (76).
Cyphocarpoideae Subfamily
The Cyphocarpodeae is a small subfamily endemic to Chile and is made of annual or perennial spiny herbs with deeply lobed leaf margins and foliaceous bracts. The upper corolla lobe is sub-hooded, and the lower lobes show three ridges.
Genera of the Cyphocarpoideae Subfamily
Cyphocarpus (4).
Key Differences From Similar Families
Campanulaceae is easy to distinguish by the combined presence of latex, simple leaves, and an inferior ovary. Sometimes plants from Acanthaceae, Lamiaceae, and Rubiaceae with long reddish or orange corolla tubes are placed in Campanulaceae, but they differ in leaves that are usually opposite and having free stamens and anthers.
Scientific Botanical Description of the Campanulaceae Family
Habit & Leaf Form of the Campanulaceae Family
Mostly perennial herbs with some annual or biennial and a few shrubs or small pachycaul trees with heights from 8 cm to over 2 m tall (excluding trees). They are laticiferous, which is an important identifying characteristic. Variously hydrophytic to xerophytic, and when hydrophytic, they are rooted with emergent and submerged leaves. Other plants may or may not have a basal aggregation of leaves. Leaves usually alternate or sometimes are opposite or whorled.
Leaves are petiolate or subsessile, sheathing or non-sheathing, and when sheathing, they have free margins. Leaves are not gland-dotted; they lack a pulvinus and stipules and are usually simple or sometimes compound–pinnate. Lamina, when simple, may be dissected or entire. When entire, it is linear, lanceolate, oblanceolate, oblong, ovate, obovate, or orbicular. When dissected, it is pinnatifid or palmatifid. Lamina margins are crenate, serrate, or dentate.
Flowers of the Campanulaceae Family
Plants are always hermaphrodites. Pollination is entomophilous and conspicuously specialized via modifications of the style with sterile tissue covering the stigmas. Flowers are solitary or aggregated in cymes, racemes, spikes, and umbels, sometimes pseudanthial. Inflorescences are scapiflorous or not, terminal or axillary, and with or without involucral bracts. Flowers are medium to large; regular to very irregular; 5-merous; tetracyclic. Perianth has a distinct calyx and corolla of 10 or 16–20 (Michauxia) parts in 2 whorls.
Calyx 5 or 8–10 (Michauxia); 1 whorled; free or connate (depending on interpretation, with the tube nearly always being united with the ovary); basally appendaged (e.g., Campanula with adjoining pairs of sepals contributing to each appendage); spurred or not; imbricate or valvate. An epicalyx is sometimes present. Corolla 5 or 8–10 (Michauxia); 1 whorled; connate (usually) or free (Jasione); valvate; often campanulate with long tubular bells or open starry ones; bilabiate or regular; mostly blue, but also white, yellow, red, pink, or purple; spurred (e.g., Heterotoma) or not spurred.
Androecium of the Campanulaceae Family
There are 5 or 8–10 (Michauxia) androecial members made of exclusively fertile stamens that are free of the perianth or adnate low down on the corolla and free of one another or coherent, 1-whorled, and sometimes forming a column around the style. Stamens are isomerous with the perianth, opposite the sepals, and alternating with the corolla members; they are filantherous or laminar and filantherous (e.g., being laminate below the filaments in Wahlenbergia). Filaments are sometimes basally appendiculate (sometimes in Campanula). Anthers are cohering and sometimes terminating an androecial column (e.g., Centropogon, Burmeistera) or separate, dehiscing via longitudinal slits, introrse, and tetrasporangiate.
Gynoecium of the Campanulaceae Family
The gynoecium is 2, 3, 5 (8 in Ostrowskia) or 8–10 carpelled (Michauxia). The pistil is 2 or 3 celled or occasionally 5 (6–10) celled. The gynoecium is synstylovarious and with a usually inferior ovary or rarely superior. The ovary is 2, 3, or 5 (6–10) locular. Styles 1. Stigmas equal in number to carpels; wet or dry type; papillate or non-papillate; Group II or IV type. Placentation axile with 10–50 ovules per locule; horizontal; non-arillate; anatropous; unitegmic; tenuinucellate.
Fruit of the Campanulaceae Family
The fruit of the Campanulaceae is almost always a non-fleshy, dehiscent septicidal, loculicidal, valvular, or irregularly splitting capsule or, rarely, a fleshy indehiscent berry. Seeds are small, endospermic, oily, and rarely starchy and are sometimes winged.
Global Distribution of the Campanulaceae
The Campanulaceae are found from frigid zones to tropical climates with a cosmopolitan distribution excluding tropical Africa and Antarctica. Found from deserts to rainforests and the Arctic, but the majority of species are by far northern temperate species.
In the Americas, the Campanulaceae are found through Canada, including the Arctic (and Greenland), and south through the USA, Mexico, Central America, and South America.
Distribution of Campanulaceae in the Americas
Canadian CampanulaceaeGenera
Campanuloideae in Canada
Campanula 19 spp., including 18 native in all of Canada, including the Arctic (and Greenland), and 1 sp. intro to BC; Githopsis 1 W NAM endemic sp. native to S Vancouver Island, BC; Heterocodon monospecific W NAM endemic native to BC; Jasione 1 sp. intro to BC?; Triodanis 1 sp. native to BC, ON, and QC.
Lobelioideae in Canada
Downingia 2 spp. native to BC, AB, and SK; Isotoma 1 sp. intro to BC; Lobelia 2 spp. native to BC, ON, and QC, and ephemeral NB.
USA CampanulaceaeGenera
Campanuloideae in the USA
Asyneuma 1 sp. native to OR and CA; Campanula 34 spp., including 33 native to most of the USA and AK but excluding OK, AR, LA, MS, and 1 sp. intro to NV and NH; Clermontia 22-23 narrow endemic spp. of HI; Cyanea 80-81 spp. narrow endemic genera of HI; Githopsis 4 spp. W NAM endemic genera native MT, WA, OR, and CA (2 endemics); Heterocodon monospecific W NAM endemic native to WA, OR, CA, NV, ID, MT, WY, and CO; Jasione 1 sp. intro to WA, OR, NC, MD, PA, DE, NY, CT, NJ, RI, and MA; Legousia 1 sp. intro to CA and PA; Platycodon 1 sp. intro to NY, PA, NC, and HI; Triodanis 6 spp. native to all of the USA (5 endemics), and intro HI; Wahlenbergia 2 spp. intro to TX, LA, AR, MS, AL, GA, SC, NC, and FL.
Lobelioideae in the USA
Brighamia 2 spp. narrow endemic genera of HI; Delissea 15 spp. narrow endemic genera of HI; Downingia 13 spp. native to WA, ID, MT, OR, WY, CA, NV, and UT, includes 9 USA endemics, mostly in CA; Hippobroma monospecific intro to FL and HI; Howellia monospecific W USA endemic of WA, ID, MT, OR, and CA; Legenere monospecific Americas disjunct endemic of CA + Patagonia; Lobelia 43 spp. native and intro to the entire USA and HI and native in AK; Palmerella monospecific narrow endemic of S CA + N BC Mexico; Porterella monospecific endemic of OR, ID, WY, CA, UT, and AZ; Trematolobelia 8 spp. narrow endemic genera of HI.
Nemacladoideae in the USA
Nemacladus 18-26 W NAM endemic spp. native to OR, ID, CA, NV, UT, AZ, and NM, including many endemic to W USA.
Mexico CampanulaceaeGenera
Campanuloideae in Mexico
Campanula 1-2 spp. native to NE Mexico and intro to SW+SE Mexico and Ver; Githopsis 1 W NAM endemic sp. native BC and Guadalupe Is.; Heterocodon monospecific W NAM endemic native to NW Mexico; Triodanis 1 sp. native throughout Mexico except the SE.
Lobelioideae in Mexico
Centropogon 4+ spp. mostly neoendemic, native to most of Mexico except the NW, and includes 1 endemic species;Diastatea 8 spp. including 7 endemics native to most of Mexico (exc. NW); Downingia 1 sp. native to NW Mexico; Heterotoma monospecific neoendemic native to NE+C+SW+NE Mexico; Hippobroma monospecific intro to all of Mexico; Lobelia ~86 spp., including ~20 endemic to all of Mexico; Palmerella monospecific narrow endemic of S CA + N BC Mexico; Wimmeranthus monospecific endemic of SW Mexico.
Nemacladoideae in Mexico
Nemacladus 10 W NAM endemic spp. native to NW Mexico, mostly in BC, including 1 endemic to BC; Pseudonemacladus monospecific endemic to NE Mexico.
Neotropical CampanulaceaeGenera
Campanuloideae in the Neotropics
Triodanis 1 sp. native to Guatemala, Colombia, Ecuador, Peru, Bolivia, Paraguay, S+SE Brazil, Uruguay, and Argentina, and intro to Jamaica and Dominican Republic; Wahlenbergia 6 spp. neoendemics of E+S Brazil (inc. 1 Brazil endemic), Colombia, French Guiana, Peru, Ecuador, Bolivia, Paraguay, Argentina, C Chile, and Uruguay.
Cyphocarpoideae in the Neotropics
Cyphocarpus 3 spp. narrow endemic genera of N+C Chile.
Lobelioideae in the Neotropics
Burmeistera 129 spp. neoendemic genera of Guatemala, Honduras, Costa Rica, Panama, Colombia, Venezuela, Ecuador, and Peru; Centropogon ~211 spp. mostly neoendemic native to CAM (exc. Belize) and tropical SAM S to Peru, Bolivia, and C+SE Brazil, and the Lesser Antilles (2 endemics); Diastatea 2 spp. native to CAM (exc. Belize), Colombia, Venezuela, Ecuador, Peru, Bolivia, and NW Argentina; Heterotoma monospecific Mexico and neoendemic native to Guatemala, El Salvador, Honduras, Nicaragua, and Costa Rica; Hippobroma longiflora monospecific originally endemic Jamaica but widely introduced elsewhere; Lobelia ~50?? spp. native to CAM, the Antilles, all of SAM except Guyana and including Galapagos; Lysipomia 32 spp. Andes endemic genera of Venezuela, Colombia, Ecuador, Peru, and Bolivia; Siphocampylus 237 spp. neoendemic genera of Costa Rica, Panama, the Greater Antilles, Colombia, Venezuela, Ecuador, Peru, Bolivia, Brazil (exc. N), Paraguay, N Argentina, and Uruguay.
Patagonia Campanulaceae Genera
Campanuloideae in Patagonia
Campanula 1 sp. intro to S Argentina and Falkland Is.; Triodanis 1 sp. native to S Argentina; Wahlenbergia 1 sp. native to S Chile.
Lobelioideae in Patagonia
Downingia 1 sp. native throughout Patagonia (also native in California); Legenere monospecific Americas disjunct endemic of California + Patagonia; Lobelia 5+ spp. native throughout Patagonia and Falkland Is. and intro to South Georgia Is.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, along with my own personal observations throughout North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
FNA (1993+). Flora of North America. https://floranorthamerica.org/Main_Page. Accessed 2022-current.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019+). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
19 Apr, 2026
29 Mar, 2023
Learn How to Identify the Apiaceae or Carrot Family
Daucus carota inflorescence with flowers. Flat-topped umbels of white flowers are quite common among the Apiaceae. Page Last Updated August 27, 2026.
Introduction to the Apiaceae Family
The Apiaceae family is widespread globally but is particularly common in northern temperate zones. It is well known for its many edible foods and herbs, including carrots, celery, parsley, dill, and many, many more. Most plants have a characteristic smell and possess small flowers in umbels, making the family fairly easy to spot in the field.
The Apiaceae are part of the Apiales order of core dicot flowering plants. The very closely related Araliaceae family has many overlapping characteristics. In general, though, Apiaceae are usually herbs that produce dry fruits that split into 2 segments when mature (schizocarps), while the Araliaceae are usually shrubs or trees and usually produce berry-like drupes (soft fruits with a pit inside, like a cherry).
Beginner’s Guide to the Carrot (Apiaceae) Family
If you’re new to plant morphology, this guide is a great beginner’s description for learning to identify the Carrot or Apiaceae family, with no need to know any scientific jargon. For researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below.
Leaves and Stems of the Carrot Family
Most plants are strongly aromatic (pleasant or not) annual, biennial, or perennial herbs. Their stems are often hollow between the nodes and are typically grooved or ribbed like celery and are often covered with hairs. The leaves are arranged alternately on the stem and often have sheaths or wrap around it. The leaves are often compound, made of many smaller leaflets.
Flowers of the Carrot Family
Flowers are usually rather small but are grouped into often large, flat-topped clusters called umbels for how they resemble the ribs of an umbrella. Each flower typically has five free white or yellow petals, or occasionally pink or purple. Flowers in the center of the cluster are often symmetrical, while those on the outer edge often have larger outer petals and smaller inner petals.
Reproductive Features of the Carrot Family
Flowers are bisexual, with both female (ovary, style, and stigma) and male (stamens) parts in the same flower. There are 5 free (unjoined) stamens. There is a single inferior ovary (located below where the petals attach), with two styles (pollen-collecting tubes) on top that often have thickened bases (stylopodium).
Fruits of the Carrot Family
Fruits are not fleshy but are small dry “schizocarps” that split into two parts, each containing a single seed when mature.
Morphology of Apiaceae in North America
Some of the Apiaceae Species Found in North America
Apioideae Subfamily
Anthriscus sylvestris—Cow Parsley
Herbaceous perennial, 60 – 170 cm tall with hollow, grooved stems that are green with purple splotches and tiny hairs. Leaves are compound and made of many leaflets (2-3 times pinnate) and appear fern-like. Flowers are white, small, in compound umbels like shown in the photo, with individual umbelets having hairy oval little bracts with red tips. It is native to Eurasia and Africa but widely introduced in the Americas.
Bifora Americana—Prairie Bishop
Herbaceous annual to 80 cm tall with deeply divided leaves with threadlike leaflets and tiny white flowers in compact compound umbels with individual petals having notched tips that help in their identification. Fruits are small, roundish dry fruits that split apart at maturity (schizocarp). This species is endemic to the southern USA, in Texas, Oklahoma, and Arkansas. This one was in Texas.
Chaerophyllum procumbens – Spreading Chervil
Herbaceous annual, 15 – 50 cm tall, with slender, branching, shiny, and finely hairy stems. Mostly hairless leaves are divided into many leaflets and look very fern-like (bipinnately compound). Flowers are in small terminal compound umbels, each with 1 to 7 small white flowers that bloom before the umbel finishes expanding, as shown in the photo. This Apiaceae species is endemic to eastern North America.
Chaerophyllum tainturieri – Hairyfruit Chervil
Herbaceous annual to 80 cm tall with erect stems, opposite compound leaves (bipinnately like many Apiaceae) that are stiff-hairy. Flowers are in few-flowered umbels (not compound) in leaf axils, and it produces oblong fruits (schizocarps) also visible in the photo. It is native to the southeastern USA, with disjunct populations in Arizona and New Mexico.
Cicuta douglasii – Western Water Hemlock
Herbaceous semi-aquatic perennial from thick tuberous roots. Inner tubers and stem bases have horizontal chambers used to help identify them. Leaves are alternately arranged and divided (pinnate) into 3 – 10 cm leaflets with jagged margins. The flowers are arranged in compound umbels with numerous small white flowers. This Apiaceae is the most poisonous native North American plant. It is endemic to the Pacific Northwest, mostly in BC, Canada, where this one was.
Cicuta maculata – Spotted Cowbane
Herbaceous perennial from rhizomes with a hollow, erect stem up to 1.8 m tall. It has compound leaves with several lance-shaped, pointy-tipped, toothed leaflets 2 – 10 cm long. Flowers are in compound umbels with many white or whitish flowers. The whole plant is poisonous and is native from northern Canada to southern Mexico.
Conium maculatum—Poison Hemlock
Herbaceous biennial 1.5 – 2.5 m tall with hairless, smooth, green, hollow stems usually streaked with red or purple. Leaves are finely divided and lacy-looking (2 – 4 times pinnately compound) and about 50 cm long. Flowers are small and white in loose compound umbels. Native to Eurasia and Africa, widely introduced and invasive in North America.
Herbaceous perennial from a taproot with a basal rosette of 3 times pinnately compound leaves. Flowers are in compound umbels in yellow. The fruit is a schizocarp. This Apiaceae member is narrow native endemic of the Sacramento and Guadalupe Mountains of New Mexico and Texas, USA.
Daucus carota—Wild Carrot
Herbaceous biennial, 30–120 cm tall with a roughly hairy, stiff, solid stem. Finely divided leaves (tripinnate) are 5 – 15 cm long and alternately arranged. Flowers are small and whitish in large, dense, flat-topped terminal umbels, often with a central pink or purple flower visible here. Dry fruits (schizocarps) develop as the umbels contract and become congested. It is native throughout the temperate Old World and has been widely introduced in the Americas.
Daucus pusillus—American Wild Carrot
Slender, herbaceous annual to 60 cm tall with hairy stems and finely dissected fern-like leaves with umbels of white flowers (lacking a central purple flower as in D. carota), with feathery bracts that extend beyond the flowers. The photo shows the contracted umbel in fruit. Native throughout the temperate Old World and widely introduced in the Americas.
Heracleum mantegazzianum – Giant Cow Parsnip
Herbaceous perennial 2 – 5 m tall with a hollow, rigid, erect green stem with prominent red-purple splotches and coarse white hairs. Leaves are about 1 m wide, deeply lobed, with shredded (incised) margins. White or green-white flowers in compound umbels are flat-topped and massive, up to 1 m across. This Eurasian native is widely introduced and invasive. It causes phototoxicity and contact dermatitis.
Heracleum maximum—Cow Parsnip
Herbaceous perennial plant to 3 m tall with hollow, densely hairy stems that have few to no purple splotches. Leaves are 3-lobed and may be deeply so but not shredded (incised) on the margins and are up to 40 cm across. White flowers in compound umbels up to 30 cm across may be flat-topped or rounded, with outer flowers often much larger than inner flowers. Native to Canada & most of the USA, plus East Asia.
Lomatium grayi—Gray’s Lomatium
Herbaceous perennial with divided, fernlike (pinnately compound) dark-green leaves. Compound umbels each with hundreds of yellow flowers appear on leafless stalks. Hairless fruits are elliptic with lateral wings. The plant smells of parsley. It is endemic to the western United States, and this one was found on Antelope Island, Utah.
Lomatium foeniculaceum – Desert Biscuitroot
An herbaceous perennial herb up to 30 cm tall from a taproot. It’s stemless with hairy leaf stalks and peduncles that grow from the ground. Leaves are compound and fern-like (2–4x pinnate) and up to 30 cm long. Flowers are small, yellow, or purplish in compound umbels. The plant smells and tastes of parsley. It is native to western and central North America. This photo was taken at Gloss Mountain, OK, USA.
Lomatium multifidum—Fern-leaved Desert Parsley
Herbaceous perennial 30 – 140 cm tall that may be hairless, hairy, or sandpapery to the touch, with a thin dry sheath at the base. Leaves are compound and fernlike (3x pinnate), 15–35 cm wide on a 3–30 cm petiole. Small yellowish flowers appear in compound umbels with tiny bracts. The dry fruit (schizocarp) has thick wings. This Apiaceae is native to western North America from BC, Canada, south to Baja California, Mexico.
Oenanthe sarmentosa—Water Parsley
This perennial herb grows up to 1.5 m tall with compound leaves (pinnately divided but not as fern-like as others) up to 30 cm long on long stalks up to 35 cm long. Individual leaflets are toothed and lobed. Flowers are in somewhat dense compound umbels with white to red-tinged petals. It is native to western North America from Alaska south to California.
Osmorhiza berteroi—Mountain Sweet Cicely
Fragrant herbaceous perennial with branching stems to 1m tall. Leaves are divided into 3 leaflets with toothed or lobed margins and are up to 20 cm long with a long leaf stalk. Small whitish flowers appear in small terminal compound umbels with 4 – 10 flowers in each umbellet, with central flowers often having only anthers. The dry fruit (schizocarp) is elongated, ribbed, and bristly and up to 2.5 cm long. It is native to temperate regions of both North and South America.
Osmorhiza longistylus—Aniseroot
This lovely herbaceous perennial grows to about 80 cm tall with small compound umbels made of small white flowers. It is easy to identify when you crush the leaves, as they smell of anise. This Apiaceae member is native to both North and South America.
Pastinaca sativa – Wild Parsnip
Herbaceous biennial/perennial to 1.2 m tall that is easy to identify because it smells like parsnip. Leaves are alternately arranged and compound (pinnate), made of yellow-green, diamond-shaped, and coarsely toothed leaflets. Numerous yellow flowers appear in compound umbels. The dry fruit (schizocarp) is made of 2 flattened, slightly winged sections (mericarps). It may cause photosensitivity. This native of Eurasia is widely introduced and invasive.
Scandix pecten-veneris – Shepherd’s Needle
This small herbaceous annual only grows up to 50 cm tall with compound leaves that are finely divided and fern-like. It produces small white flowers in few-rayed umbels. What it is most known for is its distinctive needle-like fruits that give it its common name. This species is native to Eurasia and is introduced throughout the USA and parts of South America.
Sium suave—Water Parsnip
Herbaceous perennial to 3 m tall with light green, hairless stems up to 5 cm thick with few branches. Leaves appear in basal rosettes or in clusters in aquatic habitats; those on the stem are alternately arranged and compound with opposite pairs and a single terminal leaflet (odd-pinnate). The flowers are in small compound umbels with 10 – 20 small white flowers. This Eurasian native is introduced in North America.
Torilisarvensis – Spreading Hedge Parsley
Herbaceous annual with slender, branching, rough-hairy stems to 1 m tall. Leaves are alternate and compound (pinnate) with deeply divided or coarsely toothed lance-shaped leaflets up to 6 cm long. Open compound umbels have few flowers per umbellet that have 5 unequal-sized petals in white with pink or red tinges. Fruits are greenish to pinkish, 3 – 5 mm long, and coated with straight or curved prickles. This species is native to Europe and has been introduced in North America.
Vesper bulbosus – Bulbous Spring-Parsley
This herbaceous spring annual grows from a large swollen taproot and has compound (2x pinnate) leaves with pale gray-green leaflets. It produces purple to pink or whitish flowers in compact umbels follwed by distinctive fruits with conspicuous tan to purplish wings. This plant is endemic to the western United States.
Saniculoideae Subfamily
Eryngium yuccifolium—Rattlesnake Master
Herbaceous perennial to 1.8 m tall with 15 – 100 cm long, stiff, 1 – 3 cm wide, sharp-tipped, waxy blue-green leaves with spiny margins. Flowers are in dense, round, terminal flowerhead-like umbels made of 10 – 40 tiny condensed flowers with a faint honey scent and a spiny green bract beneath them, with another cluster of spiny bracts beneath the round umbel, just visible in the photo. It is native to the tallgrass prairies of the central and eastern USA.
Sanicula canadensis—Canadian Blacksnakeroot
Herbaceous biennial or perennial 0.3 – 1.4 m tall with compound leaves made of 3 (trifoliate) egg-shaped or elliptic leaflets. Small pale green flowers in tiny bur-like compound umbels have sepals that are longer than their petals. These are followed by bur-like dry fruits (schizocarps) that split into two parts (mericarps). It is native to eastern North America, west to Wyoming, USA.
Uses and Cautions of Apiaceae
Many members of the Apiaceae family are used for culinary purposes, including Daucus (carrot), Pastinaca (parsnip), Apium (celery), Petroselinum (parsley), Pimpinella (anise), Carum (caraway), Anethum (dill), Anthriscus (chervil), Foeniculum (fennel), and Levisticum (lovage), to name some of the more common ones. Ornamental ones include Eryngium, Angelica, Heracleum, Trachymene, and others; however, many ornamentals have been modified with enlarged bracts or sepals and are not representative of the family.
Many Apiaceae are also used medicinally in folk, herbal, and Chinese medicines to treat a wide variety of ailments.
Still other Apiaceae members have notoriously poisonous resins or alkaloids such as Cicuta, Conium (hemlocks), Aethusa (fool’s parsley), and others are phototoxic (Heracleum mantegazzianum).
Ecosystem and Wildlife Values of the Carrot Family
Taxonomy of the Apiaceae Family
There are about 3,820 species in 444-466 genera in the Apiaceae family, also often called the Umbelliferae after their characteristic umbels of flowers. They are part of the Apiales order, belonging to the Asterids within the core eudicots. The Apiaceae family is further divided into four main subfamilies below, as well as a few unplaced genera.
Note that Angelica (Apioideae member) looks like it is being split so that the North American species may now/soon be considered Archangelica, while many Eurasian species have been moved to other groups as the genus gets reduced by ~100 species, so I give the species numbers in a range, and the distribution data for the USA and Canada below still call it Angelica until I can get enough sources in agreement.
Apioideae Subfamily
The Apioideae is the largest subfamily (~90% of all Apiaceae species) and is a diverse group of annual to perennial herbs or subshrubs or, rarely, a small tree. Leaves are usually pinnately divided or ternately compound, but sometimes that may be palmately divided or simple and entire. Inflorescences are almost universally compound umbels, but rarely are they reduced or capitate. Fruits are almost universally a dry schizocarp with two 1-seeded mericarps that may or may not be flattened, winged, or ribbed but almost always contain specialized oil ducts (vittae) in the mericarps. They have a cosmopolitan distribution.
The Azorelloideae are annual herbs or small shrubs, often hummock-forming. Leaves are simple, trifid to palmately lobed, and possess a sheathing petiole with stipular margins or true stipules, separating them from the Apioideae. Fruits are also shizocarps that split into two 1-seeded mericarps, but they have a woody endocarp and lack the vittae seen in Apioideae and often have prominent wings. They are mostly South American, particularly in the Patagonia region.
The Mackinlayoideae are annual herbs to shrubs. Leaves may or may not be pedately compound, palmate to simple, and are stipulate. Fruit is sometimes drupaceous but mostly still schizocarps lacking vittae but possessing a woody endocarp, like Azorelloideae, but they are typically laterally compressed. They are widespread in Australasia, Malesia, South Africa, and Madagascar, with some in South America.
The Saniculoideae are a diverse group of annual herbs and subshrubs to trees. Leaves may be tripinnately or palmately compound or simple and often palmately lobed, and some have hairy or spiny teeth. Inflorescences are usually simple umbels or capitula, and bracts may be foliaceous or petaloid. Fruits are schizocarps that may be barely to strongly compressed dorsally or laterally and are commonly adorned with scales, wings, spines, hooks, or prickles. They have a cosmopolitan distribution.
These are early-diverging lineages that fall outside the circumscription of the four subfamilies, typically exhibiting transitional characters that make them difficult to place.
Hermas (9), Klotzschia (3),Platysace (23).
Scientific Botanical Description of the Apiaceae
Below is for citizen scientists, researchers, or anyone who wants to dive deeper into the world of botany to learn more about the Apiaceae family. Note that most botanical terms have a hover-over definition to help you better understand what they mean.
Habit & Leaf Form of the Apiaceae
Plants of the Apiaceae are usually soft-stemmed aromatic annual, biennial, or perennial herbs, but some have tough stems, and a few are even woody, tree-like, or shrubby species in the tropics. Plants may be helophytic, mesophytic, or xerophytic (e.g., Eryngium), and stems are frequently hollow between leaf joints and are often ribbed (e.g., Angelica). Modified growth habits include plants that are succulent (e.g., Crithmum), or sometimes the principal photosynthesizing functions are transferred to stems (e.g., Platysace compressa) or to phyllodinous structures (petiole or rachis performs leaf function) (e.g., Lilaeopsis).
Leaves are usually well-developed but can be reduced in switch plants and occasionally are conspicuously heterophyllous (e.g., Helosciadium inundatum). Leaves are small to large and arranged alternately or alternately and oppositely (usually just oppositely on upper leaves) or rarely opposite or only in a basal rosette. Leaves are usually herbaceous but may occasionally be leathery or rarely fleshy.
Attachment to the stem is either petiolate or sometimes perfoliate or peltate; occasionally, it is pulvinate. They are nearly always possessing characteristic sheaths with free margins and may or may not be pulvinate.
Leaf arrangement may be simple or compound ternate, imparipinnate, bipinnate, multiply compound, or rarely palmate. When simple, the lamina is usually dissected pinnatifid, but it may also be palmatifid (as seen in Sanicula, Astrantia, and Eryngium), spinose (in Eryngium), or sometimes entire. They are pinnately, palmately, or parallel-veined. Leaves are usually without stipules (but sometimes with stipular flanges or true stipules in Azorelloideae and Mackinlayoideae).
Leaves may be gland-dotted and are usually strongly aromatic due to schizogenous secretory resin canals.
Flowers of the Apiaceae
Apiaceae plants are usually hermaphroditic or andromonoecious, but polygamomonoecious and strictly dioecious (Acronema) genera occur. Pollination is entomophilous. Flowers are almost always aggregated in characteristic flat-topped terminal umbels that are frequently compound, though simple umbels, dense heads, or rarely solitary flowers can occur. Sometimes inflorescences may be pseudanthial, often with sterile flowers at the periphery. The primary umbel is frequently subtended by involucral bracts and umbellets by bracteoles.
Flowers are usually actinomorphic but may be zygomorphic at the umbel edge. They are small, epigynous, and tetracyclic (5-merous, exclusive of the gynoecium). A free hypanthium is absent. The perianth is dicyclic, consisting of distinct calyx and corolla whorls, though the calyx is often very reduced.
The perianth may be sepaline (corolla usually present) or petaline (calyx teeth sometimes present) with 4–10 parts in two (or one) isomerous whorls. The petals are unequal in size, with those pointing outwards from the umbel larger than those pointing in.
The calyx, when detectable, has five parts in one whorl that may be free or connate, but typically consists of five small, free teeth, lobes, or scales; it is often reduced to a rim and never forms a tube. They are persistent in fruit and are situated at the top of the inferior ovary.
The corolla also has five parts in one whorl. The white, yellow, pink, or purple petals are always free, valvate, and may be unequal in zygomorphic marginal flowers or more equal in actinomorphic central flowers. The petals are also characteristically inflexed at the apex, with an incurved tip or notch.
Androecium of the Apiaceae
The Apiaceae androecium consists of five distinct members, all fertile stamens that are free of the perianth and of each other and arranged in a single whorl. They are equal or unequal, isomerous with the perianth, and alternipetalous (or opposite sepalous when sepals are present) on the margin of an epigynous glandular disc.
Filaments are characteristically inflexed in bud, uncurling and straightening at anthesis.
Anthers are tetrasporangiate, dithecal, introrse, and predominantly dorsifixed or sometimes sub-basifixed and dehisce via longitudinal slits.
Gynoecium of the Apiaceae
The gynoecium of the Apiaceae family is strictly syncarpous with 2 carpels with a 2-locular inferior ovary (rarely single-locular/single-seeded only through extreme reduction or abortion as in Petagnaea and Lagoecia).
The apex of the ovary is crowned with a conspicuous, fleshy, nectariferous epigynous disk called a stylopodium. Arising from the center of the sylopodium are 2 distinct, apical styles that are errect but become recurved or spreading in fruit.
Stigmas are small, terminal, wet type, non-papillate, and capitate to truncate.
Placentation is both apical and axile. Each locule bears 1 solitary fertile ovule, often with a second vestigial ovule that aborts in early development, that is pendulous. The ovules are anatropous, unitegmic, and tenuinucellallate (occasionally pseudocrassinucellate), with a ventral raphe and lacking an aril.
Fruit of the Apiaceae
The fruits of the Apiaceae are non-fleshy, specialized dry schizocarps called cremocarps. The cremocarps have two mericarps that are united across a central junction, called the commissure. At maturity, they split into two mericarps, each with a single seed. In most lineages, the separated mericarps remain pendulous, suspended by a rigid central axis called the carpophore. Mericarps are often compressed laterally or dorsally, which is a key diagnostic feature in some subfamilies and tribes.
Each mericarp typically has 5 primary riibs of varying morphology (filiform, obsucure, corky, or expanded into papery wings). In several tribes, secondary ribs are also seen. Another characteristic Apiaceae feature is the presence of oil canals called vittae located along the commissural surface.
Seeds have a thin testa, often fused to the pericarp. They are oily and endospermic.
Key Differences From Similar Families
Apiaceae are both similar to and closely related to the Araliaceae Family, and often, the two can be hard to differentiate. However, some more common differences include the fact that the Apiaceae are usually herbs vs. usually shrubs and trees in the Araliaceae; the leaves that usually lack stipules in the Apiaceae vs. usually present in the Araliaceae; and the fruit is a dry schizocarp with two mericarps vs. a berry-like drupe in the Araliaceae.
Global Distribution of Apiaceae
The Apiaceae family is a cosmopolitan family found all over the globe, from frigid arctic to tropical zones, and is found on every continent except Antarctica. However, the north temperate zone has the greatest diversity of species. In the American continents, Apiaceae occurs from Alaska, USA, and Arctic Canada all the way south to southern Patagonia and the Falkland Islands.
Distribution of Apiaceae in the Americas
Canadian Apiaceae Genera
Apioideae in Canada
Aegopodium 1 sp. intro to all of S Canada except AB and Labrador; Aethusa monospecific intro to ON, QC, NB, and NS; Anethum 1 sp. intro to S provinces except NS, NB, PE, and NL; Angelica 9 spp. native to all of Canada (& Greenland) except SK and MB; Anthriscus 3 spp. intro to BC, ON, QC, NB, NS, and NL (exc. Labrador); Astrantia 1 sp. intro to NL (exc. Labrador); Berula 1 sp. native to BC and ON; Bunium 1 sp. intro NL?; Bupleurum 2 spp. native to YT, AB, NT, BC, and intro to QC and ON; Carum 1 sp. intro to all of Canada except YT and Labrador; Chaerophyllum 3 spp. intro to BC, native in ON, and QC?; Cicuta 4 spp. N temperate genus native to all of Canada including the Arctic; Cnidium 1 sp. native to BC, YT, and NT; Conioselinum 2 spp. N temperate genus native to BC, ON, NL, NB, NS, and PE; Conium 1 sp. intro to BC, AB, SK, ON, QC, NB, and NS; Conopodium 1 sp. intro to NL Island; Coriandrum 1 sp. intro to ON, QC, and NS; Cryptotaenia 1 sp. a former NAM endemic native in MB, ON, and QC and extirpated in NB; Cymopterus 1 sp. NAM endemic genus native to AB, SK, and MB; Daucus 2 spp. including 1 native to BC and 1 intro to all of the S provinces; Erigenia monospecific E NAM endemic genus native to ON; Foeniculum 1 sp. intro to BC, ON, and QC via cultivation; Glehnia 1 sp. NW NAM endemic genus native to BC; Heracleum 4 spp., inc. 1 native to all of Canada except NU and 3 spp. intro to BC, YT, ON, QC, NB, NS, PE, and NL; Levisticum monospecific intro to AB, ON, QC, and NS; Ligusticum 6 spp. N temperate genus native to BC, ON, QC, NL, NS, NB, PE, and NU (& Greenland); Lilaeopsis 2 spp. native in BC and NS; Lomatium 20 spp. NAM endemic genus native to BC, AB, SK, and MB; Musineon 1 sp. C NAM endemic genus native to AB, SK, and MB; Myrrhis monospecific intro to BC, ON, NS, and NL Island; Oenanthe 1 sp. native to BC; Osmorhiza 6 spp. native to all of Canada; Oxypolis 2 spp. NAM endemic genus native to BC and ON; Pastinaca 1 sp. intro to all of Canada except NU; Perideridia 1 sp. NAM endemic genus native to BC, AB, and SK; Petroselinum monospecific intro to BC and ON; Peucedanum 1 sp. intro to ON and NS; Pimpinella 2 spp. intro to AB, ON, QC, NB, NS, NL (exc. Labrador); Podistera 2 spp. native to YT and NT; Sium 1 sp. native to all of Canada including the Arctic; Taenidia 1 sp. E NAM endemic genus native to ON and QC; Thaspium 3 spp. E NAM endemic genera native to ON and NS; Torilis 3 spp. intro to BC, ON, and QC; Yabea monospecific W NAM endemic genus native to BC; Zizia 2 spp. N NAM endemic genus native to all of S Canada exc. PE and NL, and inc. YT.
Saniculoideae in Canada
Eryngium 4 subcosmopolitan spp. introduced to BC, AB, SK, ON, and QC; Sanicula 9 spp. native to all of S Canada except Labrador.
USA ApiaceaeGenera
Apioideae in the USA
Aegopodium 1 sp. intro to WA, OR, ID, MT, MN, WI, IL, MO, KY, TN, GA, SC, NC, VA, WV, MD, DE, IN, OH, MI, PA, NJ, NY, CT, RI, MA, VT, NH, and ME; Aethusa monospecific sp. intro to ID, AR, MN, WI, IL, IN, OH, KY, MI, WV, PA, DE, NJ, NY, CT, RI, MA, and ME; Aletes 4 spp. S NAM endemic genus native to CO, NM, TX, and WY, including 2 narrow endemics of CO (1 of which was also in WY but has been extirpated); Ammi 2 spp. intro to OR, CA, AZ, TX, LA, MS, AL, GA, FL, SC, NC, MO, SD, and PA; Ammoselinum 2-3 spp., including 1 endemic, native to CA, AZ, NM, TX, LA, OK, KS, AR, MO, MS, TN, NC, and intro to AL; Anethum 1 sp. intro to most of the USA, including HI but excluding ID, NV, UT, WY, NM, TN, MS, AL, GA, SC, FL, VT, and NH; Angelica 22 spp. native to all of the USA, including AK, but excluding ND, SD, NE, KS, and TX; Anthriscus 3 spp. intro to WA, OR, CA, ID, MT, WY, AZ, NE, OK, MN, MO, AR, LA, GA, SC, NC, TN, VA, WV, MD, DE, WI, IL, IN, OH, MI, PA, NJ, NY, CT, RI, MA, VT, and ME; Apiastrum monospecific SW NAM endemic genus native to CA and AZ; Apium 4 spp. intro in WA, OR, CA, ID, UT, AZ, TX, OK, SD, MO, LA, IL, TN, MS, FL, SC, NC, OH, WV, PA, NJ, NY, CT, and MA; Berula 1 sp. native to all of the W USA from MN S to LA and all states W except LA and including MI and NY; Bifora 3 spp., including 1 S USA endemic of TX, OK, and AR, and 2 spp. intro to AL, PA, MD, NJ, and RI; Bupleurum 4 spp. native AK and native and intro to most of USA except WA, NV, UT, ND, NE, OK, MN, IA, WI, RI, ME, MS, and SC; Carum 1 sp. intro to the N half of USA from OR E to NJ and all N except NE and including UT, CO, NM, LA, MO, TN, KY, WV, VA, MD, and NC; Caucalis monospecific intro to PA and HI; Chaerophyllum 4 spp. intro and native to most of the E USA from ND S to TX and all E except ND, SD, MN, CT, MA, VT, NH, and ME, and including AZ and NM; Cicuta 4 spp. N temperate genus native to all of the USA, inc. AK; Cnidium 2 spp. including 1 native in AK and 1 intro to OR; Conioselinum 4 spp. N temperate genus native to most of the USA, including AK, but excluding ID, NV, ND, SD, KS, OK, TX, AR, MS, AL, SC, FL, TN, KY, WV, MD, and DE; Conium 1 sp. intro to all of the USA except MS and FL; Coriandrum 1 sp. intro to WA, OR, CA, NV, MT, ND, SD, AZ, NM, TX, OK, LA, FL, MO, IL, TN, SC, NC, VA, DE, MD, MI, OH, PA, NJ, NY, CT, RI, MA, and HI; Cryptotaenia 1 sp. former NAM endemic genus native to all of the E USA from ND S to TX and every state E; Cuminum 1 sp. intro to TX and MA; Cyclospermum 1 sp. intro to all of the S USA from NM E to NC and inc CA, NV, OR, IL, VA, WV, MD, PA, NY, and HI; Cymopterus ~40 spp. native to all of the W half of USA from ND S to TX, including MN; Cynosciadium monospecific S USA endemic genus of TX, OK, LA, AR, MO, IL, TN, MS, and AL; Daucosma monospecific narrow endemic genus of NM and TX; Daucus 2 spp., including 1 native to the W, S, and SE USA and 1 intro to all of the USA, including AK and HI; Erigenia monospecific E NAM endemic genus native to NE, OK, MO, AR, and WI S to MS and all E except FL, SC, DE, NJ, CT, RI, MA, VT, NH, and ME; Eurytaenia 2 spp. S USA endemic genus of NM, TX (1 endemic), and OK; Falcaria monospecific intro to WY, SD, NE, OK, LA, IA, MO, WI, IL, WV, VA, MD, PA, NY, and CT; Foeniculum 1 sp. intro to HI and most of the USA except ID, MT, WY, CO, ND, SD, OK, MN, AL, VT, and NH; Glehnia 1 sp. NW NAM endemic genus native to WA, OR, and CA; Harbouria monospecific C USA endemic of WY, CO, and NM; Harperella monospecific SE USA endemic of AL, AK, MS, GA, SC, NC, VA, MD, and OK; Helosciadium 1 sp. intro to CA, PA, and NJ; Heracleum 3 spp. inc. 1 native and 2 intro to most of the USA exc TX, OK, AR, LA, MS, AL, FL, and SC, and it is native in AK; Levisticum monospecific intro to CO, NM, MO, MN, MI, OH, PA, NJ, NY, CT, MA, VT, and ME; Ligusticum 11 spp. N temperate genus native to all W and E states, including AK but excluding ND S to TX and MN, IA, LA, FL, WI, IL, MI, and VT; Lilaeopsis 6 spp. native to WA, OR, CA, AZ, TX, LA, AR, MS, AL, FL, GA, SC, VA, NC, MD, NY, NJ, MA, NH, ME, and AK; Limnosciadium 2 spp. SE USA endemic genus of TX, OK, KS, LA, AR, MS, MO, and IA; Lomatium 89+ spp NAM endemic genus native to all of the W+C USA from MN S to LA and all states W exc. LA, with most being endemics of the USA; Musineon 6 spp. C NAM endemic genus native to ID, MT (1 narrow endemic), WY, CO, NV, UT, NM, ND, SD, and NE, including 5 endemic to the USA; Myrrhis monospecific introduced to OR, MI, and PA; Neoparrya monospecific narrow SW USA endemic genus of NM and CO; Oenanthe 4 spp. native to AK, WA, OR, and CA and intro to MO, OH, MD; Oreonana 3 spp. narrow endemic genus of CA; Oreoxis 2-4 spp. narrow endemic genus of UT, CO, and NM; Osmorhiza 8 spp. native to all of the USA, including AK but exc. FL and LA, including 1 US endemic; Oxypolis 4 spp. NAM endemic genera native to all of the USA except WA, ID, WY, NV, ND, SD, NE, and KS, inc. 2 endemic to S USA; Pastinaca 1 sp. intro in all the USA exc. MS, AL, GA, and FL; Perideridia 14 spp. NAM endemic genus native to W USA from MT S to NM, plus SD, KS, OK, MO, AR, IL, IN, KY, TN, AL, and MS and extinct in OH, includes 12 endemic to the USA; Petroselinum monospecific intro to WA, CA, NV, UT, ID, MT, KS, TX, LA, AR, MS, FL, GA, SC, NC, IA, MI, OH, PA, MD, NJ, NY, CT, RI, MA, and HI; Peucedanum 3 spp. intro to TN, PA, NY, WV, and MA, and 1 native to HI; Pimpinella 3 spp. intro to WA, MT, MN, WI, TN, IN, MI, OH, VA, WV, MD, DE, PA, NJ, NY, CT, MA, VT, and ME; Podistera 4 spp. native to CA, UT, CO, NM, and AK; Polytaenia 3 spp. E USA endemic genus of ND, NE, KS, OK, TX, MN, IA, MO, AR, LA, MS, AL, TN, KY, WI, IL, IN, and MI; Ptilimnium 5 spp. USA & Caribbean endemic genus native in most of SE USA (4 endemics) from KS S to TX and E to NJ except IN, OH, and inc SD, NY, CT, RI, and MA; Scandix 1 sp. intro to WA, OR, CA, AZ, TX, SD, AL, GA, FL, SC, NC, TN, OH, MI, PA, MD, NJ, NY, RI, and MA; Selinum 1 sp. intro to MA, VT, and NY?; Seseli 1 sp. intro to MD; Shoshonea monospecific narrow endemic genus of WY and MT; Sium 2 spp. native to all of the USA exc. OK but inc. AK; Smyrnium 1 sp. intro in AL; Spermolepis 9 spp. native in most of S+E USA (6 endemics) from ND S to TX except the NE states but inc. NM, AZ, CA, and HI; Taenidia 2 spp. E NAM endemic genus native in all the E half of USA from ND S to TX and all E except ME, NH, CT, FL, ND, and NE, includes 1 endemic of NE USA; Tauschia 10 spp. native to WA, ID, OR, CA, and TX, about half are endemic; Thaspium 4 spp. E NAM endemic genera native to all of E USA (1 endemic) from ND S to TX and all E exc ND, SD, NE, CT, MA, VT, NH, ME; Tiedemannia 2 spp. SE USA & Caribbean endemic genus native to TX, LA, MS, AL, GA, FL, SC, NC, and MD, extirpated in DE; Tilingia 1 sp. native to AK; Tordylium 1 sp. intro to AZ; Torilis 5 spp. intro to most of the USA except MT S to NM, also except NV, ND, SD, MN, DE, CT, RI, VT, NH, ME, and inc. HI; Trachyspermum 1 sp. intro to MI; Trepocarpus monospecific SE USA endemic genus of TX, OK, LA, AR, MO, KY, TN, MS, AL, GA, FL, and SC; Turgenia 1 sp. intro to WA, OR, and PA; Vesper 6 spp. SW NAM endemic genus native to CA, NV, ID, UT, AZ, WY, CO, NM, SD, NE, KS, OK, and TX, including 5 SW USA endemics; Visnaga 1 sp. intro to CA, OR?, AL, TX?, FL?, NC?, and PA?; Yabea monospecific W NAM endemic genus native to WA, ID, OR, CA, NV, UT, AZ, and NM; Zizia 3 spp. N NAM endemic genus native in all of the USA exc. CA, AZ, and NM, includes 1 endemic to SE USA.
Azorelloideae in the USA
Bowlesia 1 sp. native to OR, CA, NV, AZ, NM, TX, OK, LA, MS, AL, and FL.
Mackinlayoideae in the USA
Centella 2 spp. native to TX, LA, AR, MS, AL, GA, FL, SC, NC, VA, MD, DE, and NJ and intro to WA, OH, and HI.
Saniculoideae in the USA
Eryngium 34 spp. subcosmopolitan genus native and intro to all of the USA except UT, WY, MT, and ND; Sanicula 22 spp. native in all of the USA except AZ and UT, and inc. HI.
Mexico ApiaceaeGenera
Apioideae in Mexico
Aletes 1 sp. S NAM endemic genus native to NW Mexico; Ammi 1 sp. intro to SW+C Mexico; Ammoselinum 1-2 spp. native to BCN, BCS, Son, Sin, Chi, Dgo, Zac, Coa, NL, Tam, SLP, Gto, Qro, Ags, and Hgo; Angelica 2 spp. native to most of Mexico except BCN, BCS, Son, Sin, Chp, Tab, Cam, Yuc, and QR; Apiastrum monospecific SW NAM genus native to BC, BCS, Son, and Sin?; Apium 1 sp. intro to NW Mexico; Arracacia ~24 spp Mexico & neoendemic genus native to all of Mexico, including several endemics; Berula 1 sp. native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Pue, Cam, Yuc, and QR; Chaerophyllum 3 spp. native to N+SW+C Mexico and Ver, including one endemic; Cicuta 2 spp. N temperate genus native to Chi, Coa, NL, Tam, Dgo, Zac, Gto, Qro, Ags, SLP, and Hgo; Coaxana 2 spp. Mexico + CAM endemic genus native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Cam, Tab, Yuc, and QR, including 1 endemic; Conioselinum 1 sp. N temperate genus native to BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Ags, Gto, Qro, Hgo, SLP, Nay, Jal, Col, Mch, Gro, and Oax; Coriandrum 1 sp. intro to NW+C Mexico; Coulterophytum 4 spp. narrow Mexico endemic genus of Mch (1), Jal (2), Dgo + Sin + Nay (1); Cuminum 1 sp. intro to Chi, Coa, NL, Tam, Dgo, and Zac; Cyclospermum 1 sp. native to most of Mexico except BC, BCS, Son, and Sin where it is intro; Cymopterus 2-5 spp. NAM endemic genus native to much of Mexico except Mex, Cd Mex, Mor, Tlx, Pue, Ver, Tab, Cam, Yuc, and QR; Dahliaphyllum monospecific endemic genus of Nay, Jal, Col, Mch, Gro, and Oax; Daucus 3 spp., including 2 native to all of Mexico and the Mexican Pacific Is., and 1 sp. intro to NE+C Mexico; Donnellsmithia 19 spp. Mexico + N neoendemic genus native through all of Mexico, including 17 endemic to Mexico; Enantiophylla monospecific Mexico & CAM endemic genus native to most of Mexico except Ver, Tab, Cam, Yuc, and QR; Ligusticum 1-2 spp. N temperate genus native to BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Ags, SLP, Hgo, Gto, and Qro; Lilaeopsis 1 sp. native to most of Mexico except Chp, Tab, Cam, Yuc, and QR; Lomatium 1-2 spp. NAM endemic genus native to BC, BCS, Son, and Sin; Mathiasella monospecific NE Mexico endemic genus of Chi, Coa, NL, Tam, Dgo, SLP, Zac, Gto, Ags, Qro, and Hgo; Myrrhidendron 1 sp. N neoendemic genus native to Chp, Tab, Cam, Yuc, and QR; Neogoezia 5 spp. Mexican endemic genus of N+SW+C Mexico and Ver; Neonelsonia monospecific neoendemic genus native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Tab, Cam, Yuc, and QR; Oenanthe 1 sp. native to Nay, Jal, Col, Mch, and Gro; Osmorhiza 3 spp. native to most of Mexico except the SE, inc. 1 narrow endemic of NL; Ottoa monospecific N neoendemic genus native in Nay, Jal, Col, Mch, Gro, Chp, Ver, Tab, Cam, Yuc, and QR; Petroselinum monospecific intro to Mex, Cd Mex, Mor, and Pue; Prionosciadium 23 spp. Mexico & Guatemalan endemic genus native to all of Mexico, including 21+ endemic to Mexico; Rhodosciadium 15 spp. Mexico & Guatemala endemic genus native to all of Mexico (14 endemics); Spermolepis 4 spp. native to BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Ags, Hgo, SLP, and Ver; Tauschia ~22 spp. native, mostly endemics, in all of Mexico; Torilis 1-2 spp. intro to NE Mexico; Vesper 1 sp. SW NAM endemic genus native to BCN and Son; Villarrealia monospecific narrow endemic genus of Coa and NL; Visnaga 1 sp. intro to SW Mexico; Yabea monospecific W NAM endemic genus native to NW Mexico.
Azorelloideae in Mexico
Bowlesia 2 spp. native to N, C, and SW Mexico; Spananthe 1 sp. Mexico & neoendemic genus native in all of Mexico.
Mackinlayoideae in Mexico
Centella 2 spp. inc. 1 native and 1 intro to Chi, Coa, Dgo, NL, Tam, Zac, Gto, Qro, Ags, SLP, and Hgo; Micropleura 1 sp. Mexico & N neoendemic genus native to all of Mexico.
Saniculoideae in Mexico
Eryngium ~55 spp. native throughout all of Mexico; Sanicula 4-5 spp. native to all of Mexico, including 2 endemics.
Neotropical ApiaceaeGenera
Apioideae in the Neotropics
Ammi 2 spp. intro to Bermuda, Bahamas, Cuba, Hispaniola, Guatemala, El Salvador, Colombia, Argentina, S Brazil, and Uruguay; Ammoselinum 1 narrow endemic sp. of NE Argentina + Uruguay; Anethum 1 sp. intro to Guatemala, Bahamas, Greater Antilles, Leeward & Windward Is, Ecuador, Peru, NE Argentina, and S+SE Brazil; Anthriscus 1-2 spp. intro to C Chile and NW Argentina; Apium 9 spp., including 8 native to Bolivia, Chile (1 endemic), Juan Fernandez Is. (2 endemic), Desventurados Is, Argentina, Paraguay, S+SE Brazil, and Uruguay (1 endemic) and 1 intro to Guatemala, Bermuda, Cuba, Hispaniola, Puerto Rico, Trinidad-Tobago, Ecuador, and Peru; Arracacia ~35 spp. Mexico & neoendemic genus of Guatemala, El Salvador, Honduras, Costa Rica, Panama, Andes of Colombia, Venezuela, Ecuador, Peru, and Bolivia, and intro to Cuba, Hispaniola, Jamaica, Puerto Rico, and Trinidad-Tobago; Asciadium monospecific endemic genus of Cuba; Austropeucedanum monospecific narrow endemic genus of NW Argentina; Berula 1sp. native to Guatemala; Bupleurum 1 sp. intro to NE Argentina; Caucalis monospecific intro to NE Argentina; Chaerophyllum 3 spp. native to Guatemala, Costa Rica, Colombia, Ecuador, Peru, Bolivia, and Argentina, including 2 endemics of the Andes; Coaxana 1 sp. Mexico & CAM endemic genus native to Guatemala and Honduras; Conium 1 sp. intro to Guatemala, Honduras, El Salvador, Cayman Is., Hispaniola, Colombia, Ecuador, Peru, Bolivia, S+SE Brazil, Argentina, and C+S Chile; Coriandrum 1 sp. naturalized in Cuba, Hispaniola, Puerto Rico, Trinidad-Tobago, Juan Fernandez Is., Ecuador, Peru, Paraguay, S Brazil, and Argentina; Cotopaxia 2 spp. N SAM endemic genus of the high Andes of Ecuador and Colombia; Cryptotaenia 1 sp. former NAM endemic sp. intro to Colombia and Peru; Cyclospermum 3 spp. native to CAM (except Belize), Colombia, Venezuela, Ecuador, Galapagos, Peru, Bolivia, C+E+S Brazil, Paraguay, Chile, Argentina, and Uruguay, and intro to Bermuda, Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., and Juan Fernandez Is., including 2 endemics of C-S SAM; Daucus 3 spp. including 2 native to Guatemala, El Salvador, Honduras, Colombia, Venezuela, Ecuador, Peru, Bolivia, S+SE Brazil, Chile, Argentina, and Uruguay and 1 sp. intro to Greater Antilles (exc. Cayman Is.), Leeward Is., Trinidad-Tobago, Juan Fernandez Is., Desventurados Is., Peru, Argentina, Chile, Uruguay, and S Brazil; Donnellsmithia 2 spp. Mexico & N neoendemic genus native to Guatemala, El Salvador, Honduras, Nicaragua, Panama, Colombia, and Venezuela; Enantiophylla monospecific Mexico & CAM endemic genus native to Guatemala, El Salvador, and Honduras; Foeniculum 1 sp. intro in Bermuda, the Bahamas, Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., Guatemala, El Salvador, Colombia, Ecuador, Peru, Chile, Paraguay, Argentina, S+SE Brazil, and Uruguay; Helosciadium 1 sp. intro to N+C Chile and NE Argentina; Heracleum 1 sp. intro to Haiti; Klotzschia 3 spp. endemic genus of Brazil; Lilaeopsis 6 spp. native to Cuba, Dominican Republic, Colombia, Ecuador, Peru, Bolivia, Paraguay, S Brazil (1 narrow endemic), Chile, Argentina, and Uruguay; Myrrhidendron 5 spp. N neoendemic genus native to Guatemala, Honduras, Costa Rica, Panama (1 narrow endemic), and N Andes of Colombia (1 narrow endemic) and Ecuador, including 4 endemic to neotropical zone; Neonelsonia monospecific neoendemic genus native to Guatemala and Andes of SAM in Colombia, Venezuela, Ecuador, and Peru; Niphogeton 18 spp. neoendemic genus of Costa Rica, Panama, and N Andes of Colombia, Venezuela, Ecuador, Peru, and Bolivia; Notiosciadium monospecific narrow E SAM endemic genus of NE Argentina and Uruguay; Oenanthe 1 sp. intro to Uruguay and NE Argentina; Oligocladus monospecific Argentina endemic found throughout Argentina; Osmorhiza 4 spp. native to Guatemala, Colombia, Peru, Bolivia, Argentina, and C+S Chile; Ottoa monospecific N neoendemic genus of Guatemala, Costa Rica, Colombia, Venezuela, and Ecuador; Paraselinum monospecific endemic of Peru and Bolivia; Pastinaca 1 sp. intro to Greater Antilles, Ecuador, Peru, Bolivia, Argentina, C+S Chile, and Uruguay; Pedinopetalum monospecific endemic of the Dominican Republic; Perissocoeleum 4 spp. narrow endemic genus of Colombia & Venezuela; Petroselinum monospecific intro to Guatemala, El Salvador, Hispaniola, Puerto Rico, Ecuador, Peru, S Brazil, and Argentina; Pimpinella 2 spp. intro to Guatemala, Venezuela, N Argentina, and S Brazil; Prionosciadium 1 sp. Mexico & Guatemala endemic genus native in Guatemala; Ptilimnium 1 sp. USA & Caribbean endemic genus native to Cuba, Hispaniola, and Puerto Rico; Rhodosciadium 1 sp. Mexico & Guatemala endemic genus native to Guatemala; Ridolfia monospecific intro to Peru; Scandix 1 sp. intro to C Chile and NE Argentina; Seseli 1 sp. intro to C Chile; Sium 1 sp. intro to N+C Chile; Spermolepis 1 sp. endemic throughout Argentina; Tauschia 7-10 spp. native to Guatemala (2 endemics?), Colombia, Venezuela, and Ecuador; Tiedemannia 2 spp. S USA & Caribbean endemic genus native to the Bahamas and Cuba; Tordylium 1 sp. intro to NE Argentina; Torilis 2 spp. intro to Peru, Bolivia, C Chile, N Argentina, S Brazil, and Uruguay; Visnaga 1 sp. intro to Colombia, Peru, C Chile, N Argentina, Uruguay, and S Brazil.
Azorelloideae of the Neotropics
Asteriscium 9 spp. S SAM endemic genus of Chile (3 endemics) and Argentina (3 endemics in NW); Azorella ~40 spp. native to Costa Rica, Venezuela, Colombia, and through the Andes S through Ecuador, Peru, Bolivia, Chile, and Argentina; Bowlesia 16 spp. former neoendemic genus native to French Guiana, Ecuador, Peru, Bolivia, Paraguay, Chile (3), Argentina (3), Uruguay, and S+SE Brazil; Diposis 3 spp. narrow endemic genus of C Chile (1), S Argentina (1), and Uruguay (1); Domeykoa 5 spp. narrow endemic genus of Peru and N Chile; Eremocharis 9 spp. narrow W SAM endemic genus of N Chile and Peru; Gymnophyton 6 spp. Andes endemic genus of N+C Chile (6 endemic), Bolivia, and NW Argentina; Homalocarpus 6 spp. narrow endemic genus of N+C Chile; Pozoa 2 spp. S SAM endemic genus of NW+S Argentina and C+S Chile; Spananthe 2 spp. Mexico & neoendemic genera native CAM, Colombia, Venezuela, Ecuador, Peru (1 endemic), Bolivia, C +E Brazil, Haiti, and Trinidad-Tobago.
Mackinlayoideae in the Neotropics
Centella 1-2 spp. native to CAM (exc. Panama), Bahamas, Turks-Caicos, Greater Antilles, Leeward & Windward Is., Trinidad-Tobago, Juan Fernandez Is., Galápagos, Colombia, Venezuela, Brazil (exc. N), Bolivia, Paraguay, C+S Chile, N Argentina, and Uruguay; Micropleura 2 spp. Mexico & neoendemic genus native to Guatemala, El Salvador, Honduras, Costa Rica, and Colombia (1 endemic).
Saniculoideae in the Neotropics
Eryngium 100+ subcosmopolitan spp. native throughout CAM, SAM, the Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., and Trinidad-Tobago; Sanicula ~3 spp. native to CAM (exc. Belize), Colombia, Venezuela, Ecuador, Peru, Bolivia, C+S Chile, and NW+S Argentina.
Patagonian South America (Southern Argentina and Chile) ApiaceaeGenera
Apioideae in Patagonia
Ammi 1 sp. intro to S Chile and S Argentina; Anthriscus 1? sp. intro throughout Patagonia; Apium 2 spp. native throughout Patagonia & the Falkland Is.; Chaerophyllum 1-2 spp. native to S Chile, S Argentina, and Falkland Is.; Conium 1 sp. intro throughout Patagonia and Falkland Is.; Coriandrum 1 sp. intro to S Argentina; Cyclospermum 1 sp. native throughout Patagonia; Daucus 2 spp., including 1 native and 1 intro throughout Patagonia; Foeniculum 1 sp. intro throughout Patagonia; Helosciadium 1 sp. intro to S Argentina; Heracleum 1 sp. intro to S Argentina; Levisticum monospecific intro to S Chile; Lilaeopsis 1 sp. native throughout Patagonia and the Falkland Is.; Oligocladus monospecific Argentina endemic found in S Argentina; Osmorhiza 3 spp. native throughout the Patagonia region; Pastinaca 1 sp. intro to all of Patagonia; Petroselinum monospecific intro to S Argentina; Spermolepis 1 Argentina endemic in S Argentina.
Azorelloideae in Patagonia
Asteriscium 3-4 spp. S SAM endemic genus native throughout Patagonia; Azorella 15-20 spp. native throughout Patagonia and the Falkland Is., including several endemics of the Andes and Patagonia steppe; Bolax 2 spp. Patagonian endemic genus of S Chile, S Argentina, and the Falkland Is.; Bowlesia 4 spp. former endemic genus native throughout Patagonia; Diposis 2 spp. SAM endemic genus native including 1 narrow endemic of S Argentina; Homalocarpus 1 sp. narrow endemic genus of N+C Chile found near N limit of Patagonia in SC Chile; Pozoa 1-2 spp. S SAM endemic genus native throughout the Patagonia region.
Mackinlayoideae in Patagonia
Centella 1 sp. native to C+S Chile.
Saniculoideae in Patagonia
Eryngium ~17 spp. native throughout Patagonia; Sanicula 2 spp. native throughout Patagonia.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get their definitions there.
Willis, Lyrae – Unpublished. Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, as well as from personal observations of Apiaceae in North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Delta: Watson, L., and Dallwitz, M.J. (1992 onwards). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Flora of North America. (1993+). https://floranorthamerica.org/Main_Page.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009 onwards). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/ Retrieved Winter 2020 – current.
USDA, NRCS. (2020). The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
29 Mar, 2023
9 Oct, 2022
How to Identify the Apocynaceae (Dogbane and Milkweed) Family
Asclepias variegata Redring Milkweed inflorescence with flowers. The milkweeds were once their own family but are now a subfamily of Apocynaceae. Page Last Updated August 20, 2026.
Introduction to the Apocynaceae Family
The Apocynaceae family is an important family to learn how to identify. It is a family of often showy, beautiful flowers that are frequently fragrant but also often highly poisonous if ingested. The name “dogbane” comes from this toxic nature that has poisoned livestock and dogs.
The Apocynaceae was recently revised to include the former Asclepiadaceae, or milkweed, family. Molecular phylogenetics provides an excellent reason to do so, and the two families are similar in morphology and other properties. However, there are a few notable differences in the Asclepiadoideae subfamily that I have included in detail in the descriptions below.
Beginner’s Guide to the Dogbane or Milkweed Family
If you’re new to plant morphology, this section is a perfect beginner’s description to teach you how to identify the Apocynaceae family, with no need to know any scientific jargon. Below is some additional information on the uses of the Apocynaceae family, along with morphology pictures to help you identify family members, and finally, pictures of individual species found in North America.
But for researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below the images in addition to genus-level distribution data.
Leaves and Stems of the Dogbane and Milkweed Family
Perennial or annual herbs, shrubs, woody vines, and trees that all have a characteristic milky white juice (latex) (sometimes clear) that they release when damaged. Leaves are usually simple (not compound) and may be thin to thick and leathery. They are usually arranged in opposite pairs or whorls around the stem. In some species, the leaves are modified into spines, and the stem may appear cactus-like.
Flowers of the Dogbane and Milkweed Family
Flowers are often large, showy, symmetrical, and come in whites, reds, blues, and yellows and may be fragrant, foul-smelling, or odorless. Petals are joined at the base to form a funnel or trumpet shape, often with twisted or contorted lobes in bud, often appearing pinwheel-like. Most flowers have nectaries at their base to attract pollinators.
Reproductive Features of the Dogbane and Milkweed Family
There are 5 male parts (stamens) that are often fused to the female parts (ovary, style, and stigma) to create a unique central structure called a “gynostegium,” but in some lineages they are partially to fully free. There are typically two superior ovaries (which sit above where the petals attach), with a large and conspicuous style head on top that acts as a platform to receive pollen.
Fruits of the Dogbane and Milkweed Family
The fruits are most often large pod-like capsules (follicles) containing numerous seeds accompanied by long silky hairs (comose), which allow them to disperse in the wind. But sometimes the seeds are hairless, and some species produce fleshy berries or drupes (like a cherry with a hard central pit) or dry capsules.
Morphology of Apocynaceae in North America
The first table shows general Apocynaceae family morphology, but then there is a second one below it showing morphology specific to the Asclepiadoideae subfamily of the Apocynaceae.
Some Apocynaceae Species Found in North America
Apocynoideae Subfamily
Adenium obesum – Sabi Star or Desert Rose
This is a drought-deciduous or evergreen shrub that is native to Africa but cultivated elsewhere. It has large, swollen stems with a very enlarged, swollen stem (caudex). Spiral leaves are clustered at branch tips. It has tubular pink flowers 4 – 5 cm wide with 5 petals.
Apocynum androsaemifolium – Spreading Dogbane
This is a branching herbaceous perennial with opposite and more or less egg-shaped to somewhat elliptical leaves. Flowers are small, bell-shaped, whitish-pink, and found mostly in terminal clusters like these. Native throughout North America.
Apocynum cannabinum – Indian Hemp
Erect, herbaceous branching perennial with usually purplish-green stems and with opposite lance-shaped to egg-shaped leaves that usually have white hairs on the lower surface. Flowers are small greenish to cream-colored, usually in terminal inflorescences. Native throughout North America.
Nerium oleander – Oleander or Nerium
This cultivated Apocynaceae species is originally from the Mediterranean. It has thick, leathery, lance-shaped leaves in whorls of 2 – 3. Flowers are deeply 5-lobed with a fringed corolla around the mouth of the floral tube, as seen here in the center of the flower. Flowers are intensely fragrant (perfume).
Pachypodium rutenbergianum—Madagascar Palm
This is a unique-looking tree 3-8 m tall with very thick succulent branches, long spines, and an enlarged stem (caudex). It has long, leathery, oblong to lance-shaped leaves. Flowers are white with a yellow center, petals spreading in a pinwheel shape. Native to Madagascar & cultivated elsewhere.
Trachelospermum jasminoides—Star Jasmine
This is a vigorous, medium-sized evergreen shrub or vine with elliptic to egg-shaped, hairless, glossy, green, leathery leaves. Flowers are in few-flowered clusters on long stalks; they are very fragrant and hairy inside the floral tube. This Apocynaceae member is native to Asia but widely cultivated elsewhere.
Asclepiadoideae Subfamily
Asclepias arenaria – Western Sand Milkweed
Erect herbaceous perennial with densely woolly leaves and stems. Leaves are broadly egg-shaped with wavy (undulate) margins seen in the photo. Flowers are found in the leaf axils and are greenish to cream-colored. This species is endemic to the Great Plains region of the USA and is very drought-tolerant.
Asclepias asperula—Antelope Horns
This is a clump-forming, 1-2 ft tall perennial with long, narrow leaves that are usually folded lengthwise, as shown in the photo. Flowers are usually in roundish terminal inflorescences with greenish flowers with maroon highlights. The fruit are follicles that usually curve like a horn (see photo). It is native to the southwestern USA and northern Mexico.
Asclepias curassavica – Tropical Milkweed
A perennial native of South America but becoming widely introduced elsewhere. Flowers have purple or red corollas and yellow or orange coronas in the center. Leaves are long and narrow with acute tips or tapering to a point. It is not recommended to grow this plant outside of the tropics because it is confusing monarchs into overwintering in temperate climates instead of migrating.
Asclepias engelmanniana – Engelmann’s Milkweed
A tall, slender perennial with 1 – 4 branching stems with long and very narrow linear leaves, usually in groups of 2 – 3. Pale green flowers without horns are crowded in umbels in the upper leaf axils. This species is endemic to the Great Plains of the USA.
Asclepias incarnata—Swamp Milkweed
A herbaceous perennial that is branched on the upper part of the stem and has lance-shaped to linear–oblong leaves. The flower’s corolla is pink to red (rarely white), and the horn curves inward past the hood. This lovely plant is native to swamps and other wet areas of eastern North America.
Asclepias latifolia – Broadleaf Milkweed
This unbranched, 2 – 3 ft tall herbaceous perennial has very large, broad, somewhat egg-shaped or oval leaves with prominent veins. Leaves are densely packed, appearing cabbage-like when young. Flowers are pale greenish to yellow, often hidden in axils by the large leaves. Native to the western USA and northern Mexico, mostly in the Great Plains.
Asclepias pumila – Plains Milkweed
This short herbaceous perennial is usually less than 30 cm tall with narrow leaves that are densely packed, appearing whorled but not upon close inspection. Flowers are light pink or white in terminal inflorescences. This is another endemic of the Great Plains region of the USA.
Asclepias speciosa – Showy Milkweed
Herbaceous perennial up to 1.2 m tall with oppositely arranged, elongated, simple leaves. Large, hairy, pale pink to pinkish-purple flowers appear in dense umbel-like clusters and have very prominent hoods and hooks forming a star shape. Native to western North America.
Asclepias subverticillata – Horsetail Milkweed
This erect, spreading, herbaceous perennial may or may not be branched and grows to 1 m tall with sparse, narrow, linear leaves with margins that roll backward on the edge (revolute) and grow in whorls of 3 – 5 at branch nodes. Star-like whitish or cream flowers grow in the upper leaf axils. It is native to the central and southwestern USA and northern Mexico.
Asclepias syriaca—Common Milkweed
A tall perennial up to 1 m tall with large egg-shaped to somewhat elliptic leaves with pale green on the lower surface. Flowers are in somewhat drooping umbels in leaf axils and are usually pink (rarely white), with horns that bend inwards. The follicles have a very roughly textured surface (shown in the photo). Native to the eastern USA and Canada.
Asclepias tuberosa—Butterfly weed
A bushy herbaceous perennial to 60 cm tall, with a hairy stem that may or may not branch in the top half. Leaves are linear to narrowly egg-shaped and may be arranged opposite or alternate on branches. Flowers are in terminal flat-topped umbels of yellow to red-orange flowers. Native to southeastern Canada and the eastern and southwestern USA.
Asclepias variegata—Red Ring Milkweed
Herbaceous perennial with usually unbranched stems with several pairs of opposite broadly oblong to ovate leaves. Flowers in 1 – 4 rounded, compact umbels with showy white and pinkish-red-tinged flowers with spreading hoods. Native to eastern North America, rare in the north, most common in the southeastern USA.
Asclepias verticillata – Whorled Milkweed
An erect perennial with branching only at the top of the plant (or unbranched) with numerous narrow linear leaves in whorls of 3 – 6. Flowers are in several umbels crowded in the upper axils with white to greenish flowers with somewhat spreading hoods and horns that are larger than the hoods. Native to eastern North America and parts of western North America.
Asclepias viridis – Green Antelope Horns
A herbaceous perennial common on overgrazed pastures and roadsides. Simple leaves, often with wavy (undulate) edges, are arranged alternately on the stems. Flowers are green with purplish hoods, and they lack the horns usually present in the genus. This species is endemic to the south-central and some of the southeastern USA.
Cyanchum laeve – Climbing Milkweed or Sand Vine
This is a climbing vine that is sparsely hairy with opposite heart-shaped leaves with palmate veins. Flowers are in clusters of 5 – 40 flowers in the leaf axils. The fruit is an egg-shaped follicle. Native to central and eastern USA, southeastern Canada
A tendril-climbing perennial vine with linear to oblong leaves that are hairy and somewhat succulent. Flowers appear in the leaf axils and have soft-hairy white petals. This species is native to the southern USA, Mexico, and the tropical Americas.
Rauvolfioideae Subfamily
Carissa macrocarpa—Natal Plum
Spiny evergreen shrub with leathery, glossy dark green leaves. Flowers are very fragrant and white with long narrow petals. The fruit is a large, reddish, edible drupe (looks like a plum). Native to Africa, cultivated in southern North America and the tropical Americas.
Cascabela ovata—Yellow Oleander
A perennial shrub or tree with spiral, moderately thick, and leathery leaves with prominent veins (pinnate). Flowers are large, showy, tubular, and yellow. The fruit is large, ~rounded, and somewhat plum-like but with multiple large stony seeds, turning purplish when mature. Native and common in Mexico and also Central America.
Catharanthus roseus – Madagascar Periwinkle
An evergreen subshrub with hairless egg-shaped, somewhat glossy leaves arranged in opposite pairs. Flowers are white with yellow or red centers or dark pink with red centers. Native to Madagascar but frequently cultivated in North America.
Plumeria rubra – Red Frangipani
A medium to large shrub or small tree with a succulent trunk and branches. Drought-deciduous or semi-evergreen with large leaves clustered at branch ends. Flowers are white to pink and very fragrant in terminal umbels. Native to Mexico and tropical America, widely cultivated elsewhere.
Rauvolfia tetraphylla – Devil Pepper
A much-branched shrub or small tree with 4 (3 – 5) whorled egg-shaped, elliptic, or ~oblong leaves per node. Flowers are small and white and appear in clusters in the leaf axils. The fruit is a small red 2-seeded drupe (shown in the photo). It is native to Mexico and the tropical Americas.
A scrambling vine with opposite semi-evergreen leaves with a waxy surface and tiny hairs, sometimes with hairy margins. Flowers are pink to violet, fused at the base, with pinwheel-like lobes. Native to the western Mediterranean, widely cultivated as a groundcover, and highly invasive in some areas.
A scrambling vine with opposite hairless evergreen leaves that are smaller and narrower than V. major and never have a hairy margin. Flowers are similar to V. major but a little smaller. This Apocynaceae member is native to Eurasia, widely cultivated and highly invasive in some areas.
Uses of the Apocynaceae Family
Most parts of many members of the Apocynaceae family are poisonous, hence the common family name of dogbane, since it has been used to poison dogs and other animals. The sap of most is a milky latex, which is often toxic but can sometimes be used for medicine and rubber. In fact, the family is used for cardiac stimulants, chemotherapy, and hypertension in modern pharmacology.
Many ornamental shrubs, trees, herbs, and vines come from this family, including Oleander, Frangipani, Carissa, Plumeria, Vinca, Asclepias, Hoya, Araujia, Ceropegia, Stapelia,Caralluma, Decabelone, etc.
Several species in the basal Ravolfioideae are used as edible fruits, like Carissa macrocarpa, which is the source of the edible natal plum; karanda, which comes from Carissa carandas; and the wild mangaba from Hancornia speciosa.
Ecosystem and Wildlife Values of the Apocynaceae Family
The famous monarch butterfly requires Asclepias species for reproduction, depositing its eggs on the plants, which hatch into caterpillars that eat the leaves. The monarchs are able to eat the toxic sap without ill effects. Other insects like milkweed beetles, milkweed bugs, and milkweed tussock moths also feed on them, and the Danaine butterflies also depend on the subfamilies Asclepiadoideae, Apocynoideae, and Secamonoideae as larval host plants.
Many Apocynaceae flowers, especially Asclepias, Apocynum, Cynanchum, and Hoya, produce large volumes of sugar-rich nectar for a vast array of generalist native bees, honeybees, wasps, butterflies, and hummingbirds.
The silky coma hairs of Asclepias, Nerium, and Funastrum seeds are extensively used by small songbirds (goldfinches, bushtits, and hummingbirds) to line and insulate nests.
Fleshy-fruited Rauvolfioideae (such as Carissa, Landolphia, Saba, and Willughbeia) serve as critical food sources for frugivorous birds, bats, and primates in tropical ecosystems.
Taxonomy of the Apocynaceae
The Apocynaceae contains 4555 to 5100 species in 400 genera, which belong to five subfamilies. It is part of the Gentianales order of the core eudicots. The recent inclusion of Asclepiadoideae in Apocynaceae greatly increased the number of species and genera. As with most families, thanks to molecular phylogenetics, which is better clarifying our understanding of the plant families, the genera and species have been undergoing revisions. This information is up-to-date as the accepted data currently shows.
Apocynoideae Subfamily
The Apocynoideae is a diverse subfamily of perennial (rarely annual) herbs, shrubs, lianas, and the occasional tree. They exude milky latex, but it is sometimes clear. Leaves are simple and entire and usually exstipulate or have very small stipules and are otherwise quite variable. The stamens converge into a cone and adhere directly to the style head, though they lack pollinaria and do not form a fully fused gynostegium. Fruits are typically paired, dry follicles containing seeds crowned with a conspicuous tuft of silky hairs (coma) for wind dispersal.
The Asclepiadoideae is a subfamily that can usually be easily recognized by the presence of a gynostegium with its monoadelphous stamens and two styles that are partially joined (free below) to the massive style head. The two carpels are free below, joining at the style head, where lateral receptive stigmatic chambers alternate with the anthers. Pollen is aggregated into waxy pollinia, and the stamens often have complex petaloid outgrowths forming characteristic “hoods” and “horns.” Fruits are always dry, paired (or solitary by abortion) follicles containing comose seeds, and most plants exude milky latex.
The Periplocoideae are a subfamily of twining lianas, erect or climbing shrubs, geophytic herbs, or rarely small trees, exuding milky, watery, or clear sap. Colleters are characteristically present at the base/sinuses of the calyx. Filaments are distinct and inserted near the corolla base, with anthers converging over and adhering to the style head. The subfamily is differentiated by pollen shed in tetrads deposited into a spoon-shaped (spatulate) translator bearing an adhesive basal disc (lacking the paired waxy pollinia of Asclepiadoideae). Fruits are paired follicles with comose seeds for wind dispersal.
The Rauvolfioideae forms the basal grade of the Apocynaceae. They are a diverse subfamily divided into eleven tribes. In general, they are mostly pantropical trees, shrubs, and some lianas, with just a few temperate herbaceous lineages. They also have variable fruit and floral morphology but generally have stamens that are free from the style head, which separates them from the Apocynoideae and Asclepiadoideae. They also have actinomorphic flowers, usually salverform or rotate with petals often overlapping with left-contorted aestivation, giving them a “pinwheel” look. They have highly variable fruits but often produce fleshy drupes or berries, or paired dry follicles with unwinged or hairless seeds (no silky comas).
The Secamonoideae are a small subfamily of twining lianas or climbing vines; rarely, they may be shrubs (Madagascar). Leaves are simple, opposite, and entire, sometimes bearing adaxial colleters. Flowers are characteristically small to minute, with a fully developed gynostegium. The subfamily is best differentiated by its pollinia arrangement, producing 4 pollinia per pollinarium (2 per anther theca) attached to a central corpuscular translator. Fruits are paired, slender to fusiform follicles that contain comose seeds.
The Apocynaceae can be confused with the Rubiaceae (Coffee/Madder), who share opposite, entire leaves, sympetalous 4-5-merous flowers, and woody or herbaceous habit. The Rubiaceae, however, almost never have a milky latex and have prominent interpetiolar stipules and strictly inferior ovaries.
They are also confused with the Gentianaceae, which also share similar leaves without stipules and sympetalous flowers with contorted corollas, but the sap of the Gentianaceae is always clear, never milky, and they have a single syncarpous ovary. They also lack the specialized pollinia and other features of the Apocynaceae.
The Euphorbiaceae are another family occasionally confused with the Apocynaceae, mostly because of their abundant milky latex, and some succulent forms resemble succulent Apocynaceae. However, Euphorbiaceae flowers are highly reduced unisexual pseudanthaia (cyathia) subtended by petal-like glands.
Scientific Botanical Description of the Apocynaceae
This section is for researchers and others who want a more thorough, scientific botanical description of the Apocynaceae family.
Habit & Leaf Form of the Apocynaceae Family
The Apocynaceae are mostly perennial or annual herbs, shrubs, and lianas, which may be root climbers, scramblers, and stem twiners. However, some trees are also seen, which may develop buttress roots (a few in Tabernaemontana and Dyera). Some plants may be switch plants with succulent, photosynthetic stems. Others have peculiar vegetative forms, such as leaves modified into passive pitcher traps in Dischidia rafflesiana. All forms are laticiferous, containing a milky or sometimes watery or clear latex characteristic of the family.
Leaves are simple and usually well-developed but may be very reduced. They may be herbaceous, leathery, membranous, succulent, or rarely modified into spines. They are mostly attached opposite or whorled (3-8 per whorl) or rarely alternate. Stipules are usually absent or highly reduced; when present, they are often modified into colleters or pairs of sharp spines. Domatia are sometimes seen as pits, pockets, or hair tufts.
The leaf lamina is entire and is frequently pinnately veined but is sometimes one-veined or palmately veined. It is usually dorsiventral, sometimes bifacial, or isobilateral in Nerium oleander. The epidermis frequently contains crystal idioblasts, and diverse hairs are often found, which may be simple eglandular to multicellular glandular shaggy hairs at the lamina bases and on the petiole.
Flowers of the Apocynaceae Family
Apocynaceae plants are predominantly hermaphroditic, tetracyclic, actinomorphic, and 5-merous (rarely 4-merous) and adapted for specialized entomophilous pollination (often utilizing clip mechanisms, guide rails, or temporary pitfall traps). Inflorescences are terminal or axillary, solitary or arranged in cymes, panicles, thyrses, or umbelliform cymes, typically subtended by bracts and bracteoles.
The flowers are often large and showy and may be malodorous, fragrant, or odorless. A basal annular or lobed hypogynous nectariferous disk is usually present in Rauvolfioideae and Apocynoideae but is replaced by internal stigmatic chamber nectaries in Asclepiadoideae.
The perianth is biseriate with a distinct calyx and corolla. The calyx has five parts in one whorl, is usually connate (at least basally), is regular, and is quincuncial, imbricate, or valvular; the adaxial base often bears secretory colleters.
The corolla also has five parts in one whorl and may or may not be appendaged. The corolla is connate (ranging from rotate, campanulate, and salverform to tubular, funnelform, or urceolate), with lobes shorter or longer than the tube.
Aestivation is predominantly contorted, typically sinistrorse (overlapping to the left) in Rauvolfioideae and dextrorse (overlapping to the right) in Apocynoideae/Periplocoideae, or valvate in derived Asclepiadoideae. The throat or tube often bears internal appendages forming a corolline corona (Nerium, Strophanthus). Corolla colors span white, cream, yellow, green, orange, red, pink, purple, violet, and mottled brown/black.
Androecium of the Apocynaceae Family
The androecium varies heavily, depending on the subfamily. In general, it consists of a single whorl of 5 distinct, fertile stamens alternating with the corolla lobes (haplostemonous, isomerous). Filaments are epipetalous, inserted near the corolla tube base (in Asclepiadoideae and Periplocoideae), midway down the tube, or within the throat.
In Rauvolfioideae, the filaments and anthers are completely free from one another and free from the style head.
In Apocynoideae, the filaments are distinct, but the anthers are connivent (often sagittate with sterile, tailed bases) and postgenitally adhere to the style head via sticky secretions, forming an anther cone.
The Periplocoideae have distinct filaments inserting near the tube’s base. The anthers converge and adhere to the style head, shedding pollen tetrads into spoon-like translators.
In the Secamonoideae and Asclepiadoideae, the filaments are connate into a monadelphous tube that is congenitally fused to the massive style head, forming a true gynostegium. In Asclepiadoideae, anthers bear sclerified lateral guide rails (horny wings) and terminal membranous connective appendages, while the filament tube bears complex dorsal outgrowths forming a nectariferous staminal corona (hoods and horns).
Anthers are basifixed, introrse, non-versatile, and dehisce longitudinally. They are dithecal and tetrasporangiate in the basal subfamilies, reducing to bisporangiate in Asclepiadoideae (where each theca holds a single pollinium).
Gynoecium of the Apocynaceae Family
The gynoecium is typically bicarpellate (rarely 3–5 or up to 8 carpels in Pleiocarpa). Across most of the family, the carpels and their lower styles are free (apocarpous), uniting postgenitally only at the apex into a single, massively enlarged style head (synstylous). Truly syncarpous ovaries occur in select basal clades (e.g., Allamanda, Carissa).
The ovary is superior to semi-inferior (rarely inferior). The carpels are oriented transversely across most basal lineages but are oriented medially (anteroposterior) in Asclepiadoideae.
Placentation is marginal in the typical apocarpous/synstylous condition, with each free carpel bearing 2 to >100 ovules along the ventral suture, or parietal when syncarpous and unilocular (Allamanda) or axile when syncarpous and bilocular (Carissa).
Ovules are pendulous, anatropous to hemianatropous, unitegmic, and tenuinucellate (Apocynoideae/Rauvolfioideae) or pseudocrassinucellate (Asclepiadoideae).
Rather than a conventional apical receptive surface, the style head is expanded into a pentagonal, capitate, or spool-shaped structure. It is often equipped with a basal collar, a ring of hairs, or secretory translator-producing zones. The true receptive stigmatic surfaces are localized laterally or on the underside in specialized chambers alternating with the stamen attachments.
Fruit of the Apocynaceae Family
The fruits of Apocynaceae are typically a pair of dry, dehiscent follicles (follicetum) opening along the ventral suture, but it’s often solitary via abortion of one carpel.
However, in Rauvolfioideae they are more variable, often paired or solitary fibrous drupes, or berries, but may also be a spiny bivalved dehiscent capsule or large woody follicles.
Seeds are usually flat and are conspicuously comose in the Apocynoideae, Periplocoideae, Secamonoideae, and Asclepiadoideae. But they may be hairless, winged, or unadorned. Seeds are oily, and an endosperm is usually present.
Global Distribution of the Apocynaceae
The Apocynaceae are mostly subtropical to tropical shrubs, trees, and herbs, with a few temperate representatives. They are cosmopolitan in distribution, found everywhere except Antarctica. In the American continents, they are widespread throughout, including some herbaceous Apocynaceae species that reach as far north as Arctic Canada.
Distribution of Apocynaceae in the Americas
Canadian ApocynaceaeGenera
Apocynoideae in Canada
Apocynum2 spp. native in almost all of Canada, including the Arctic but excluding NU and Labrador, with 1 NAM hybrid sp. also native in this range.
Asclepiadoideae in Canada
Asclepias 15 spp. native in all S provinces but intro in NL (absent in Labrador); Cynanchum 1 sp. intro in ON; Vincetoxicum 3 spp. intro to BC, ON, QC, and NB.
Rauvolfioideae in Canada
Vinca 2 spp. intro to BC, ON, QC, NS, and NB.
USA Apocynaceae Genera
Apocynoideae in the USA
Apocynum 2 spp. native to all of the USA, including AK, plus 1 NAM hybrid sp. native in this range; Beaumontia 1 sp. intro HI; Cycladenia monospecific SW USA endemic to CA, OR, AZ, and UT; Echites 1 sp. native to FL; Mandevilla 4 spp. native to AZ, NM, and TX; Nerium monospecific sp. intro to most of S border states exc. NM, also in UT and CA; Pentalinon 1 Mexico, CAM & Caribbean endemic sp. native to S FL; Rhabdadenia 1 S NAM & neoendemic sp. native to FL; Thyrsanthella monospecific SE USA endemic to OK, TX, MO, AR, LA, IL, IN, KY, TN, MS, AL, GA, FL, SC, NC, VA, and DE; Trachelospermum 2 spp. intro to TX, OK, MO, AR, LA, MS, AL, GA, FL, SC, NC, VA, MD, DE, TN, KY, IL, and IN.
Asclepiadoideae in the USA
Araujia 2 former neoendemic spp. intro to CA, GA, and FL; Asclepias 75 spp. native to all the continental states and HI, with some intro in some states; Calotropis 2 spp. intro to CA, FL, and HI; Cynanchum 17 spp. native and intro to most of the USA exc WA, OR, WY, MT, CO, ND, and SD; Funastrum 5-7 spp. native to CA, NV, UT, CO, AZ, NM, TX, OK, AR, and FL; Gomphocarpus 1 sp. intro to CA?; Gonolobus 3 spp. native to AZ, KS, OK, TX, MO, AR, LA, IL, IN, KY, TN, MS, AL, GA, FL, NC, SC, VA, and MD; Hoya 1 sp. intro to HI; Matelea 24 spp. (may be less now that genus has been reduced) sp. native to the most southern states; Metastelma 7 spp. native to AZ, NM, TX, and FL; Orthosia 2 spp. native to MS, FL, GA, and SC; Pherotrichis 1 sp. native to AZ;Suberogerens monospecific endemic of W+SE Mexico, and Ver; Vincetoxicum 3 spp. intro to CA, NE, KS, MN, MO, MI, WI, IL, IN, KY, OH, PA, NJ, MD, NY, CT, RI, MA, VT, NH, and ME.
Periplocoideae in the USA
Cryptostegia 2 spp. intro to TX and FL; Periploca 1 sp. intro to KS, OK, TX, TN, VA, PA, NJ, NY, CT, and RI.
Rauvolfioideae in the USA
Allamanda 1 former neoendemic sp. intro to FL; Alstonia 1 sp. intro to FL and HI; Alyxia 1 Pacific sp. native to HI; Amsonia 16 spp., including 14 native to all of S USA from CA E to NJ but excluding WV, which includes 7 endemic to the USA and 3 narrow endemics of AZ (2) and NM (1), and includes 2 spp. intro to NY, CT, and MA; Carissa 1 sp. intro to AZ, TX, and FL; Catharanthus 1 sp. intro to CA, TX, LA, MS, FL, GA, SC, NC, OH, and HI; Haplophyton 1 S NAM & N CAM endemic spp. native to AZ, NM, and TX; Ochrosia 4 spp. native to HI and intro to FL; Plumeria 1 sp. native FL; Pteralyxia 2 spp. endemic genera of HI; Rauvolfia 3 spp. inc. native in FL, and intro and native in HI; Tabernaemontana 2 spp. native to FL and intro HI; Thevetia 1 Neo sp. intro to TX, FL, and HI; Vallesia 2 spp., including 1 native and 1 intro to CA and FL; Vinca 3 spp. intro to most of the USA, except NV, OK, CO, WY, ND, and SD.
Mexico ApocynaceaeGenera
Apocynoideae in Mexico
Apocynum 1 sp. native to N Mexico, plus 1 NAM hybrid sp. native in this range; Echites 7 NAM, CAM & Caribbean spp. native to most of Mexico, exc. BC, BCS, Son, and Sin, and inc. 1 endemic to SW+C Mexico; Forsteronia 1-3 spp. neoendemic genus native to SW+SE Mexico, Ver, Chp; Laubertia 1 Mexico endemic sp. in most of Mexico exc. Ver; Mandevilla ~22 spp. native (~1/2 endemic) to all of Mexico; Mesechites 1 Mexico & Neoendemic sp. native to Mexico except for BC, BCS, Son, Sin, Mex, Cd Mex, Pue, Tlx, and Mor; Nerium monospecific sp. intro to most of Mexico exc. BC, BCS, Son, Sin, and Ver; Odontadenia 1 neoendemic sp. native SW+SE Mexico, Chp; Pentalinon 1 sp. native SW+C+SE Mexico; Pinochia 2 spp. Mexico & N neoendemic genus native to SW+SE Mexico, Chp, and Ver; Prestonia ~5 spp. native to most of Mexico exc. BC, BCS, Son, and Sin; Rhabdadenia 1 S NAM & neoendemic sp. native to Ver, Cam, Tab, Yuc, QR, and Chp; Thenardia 3 spp. Mexico & Honduras endemic genus native to SW+C+SE Mexico, inc. 2 endemics; Thoreauea 3 spp. endemic genus of SW Mexico + Ver; Tintinnabularia 2 spp. Mesoamerica endemic genus native to Oax, Chp, and Ver, inc. 1 narrow endemic of Ver.
Asclepiadoideae in Mexico
Asclepias 70+ spp. native to all of Mexico; Calotropis 1 sp. intro to SW+C+SE Mexico; Cynanchum several spp. native to all of Mexico; Fischeria 1 Neoendemic sp. native to SW+C+SE Mexico; Funastrum 13 spp. native throughout all of Mexico, including 3 endemics; Gomphocarpus 1 sp. intro to SW Mexico; Gonolobus ~50 spp., about half of which are endemic and native to all of Mexico; Jobinia 1 sp. native Ver; Macroscepis 5 Mexico & neoendemic spp. native to all of Mexico, including 2 narrow endemics; Matelea ~70 spp., ~60% endemic to all of Mexico; Metastelma ~30 spp. native to all of Mexico, including Mexican Pacific Is., including many endemics; Orthosia 9 spp. inc. 6 endemics native to all of Mexico; Oxypetalum 1-2 spp. native to NE+SW+SE Mexico and Ver; Pherotrichis 4 spp. Mexico & N CAM endemic genus native to most of Mexico except Ver, including 2 Mexican endemics of SW Mexico; Ruehssia ~40 Mexico & neoendemic spp. native to all of Mexico, with ~68% endemism; Stelmagonum is monospecific and endemic to SW Mexico; Talayotea 2 spp. endemic genera of most of Mexico except Ver; Tassadia 1 neoendemic sp. native to SW+SE Mexico and Ver.
Periplocoideae in Mexico
Cryptostegia 2 spp. intro to W+SE Mexico.
Rauvolfioideae in Mexico
Allamanda 1 former neoendemic sp. intro to SW+C Mexico; Alstonia 1 sp. native to SW+C+SE Mexico; Amsonia 4 spp. native to N Mexico; Aspidosperma 5-7+ neoendemic spp. native to SW+SE Mexico, Ver., including 2 endemics; Cameraria 1 former Mexico + N neoendemic sp. native to SE Mexico; Carissa 1 sp. intro to SW+C Mexico; Cascabela 5 spp. native to all of Mexico, including 3 endemics; Catharanthus 1 sp. intro to SW+SE Mexico; Haplophyton 2 S NAM & N CAM endemic spp. native to most of Mexico except Ver; Plumeria 2 spp. native to all of Mexico; Rauvolfia 3-4 spp. native to all of Mexico; Tabernaemontana ~16 spp. native to all of Mexico, including 6 endemics; Thevetia 1 sp. native to most of Mexico except BC, BCS, Son, and Sin; Vallesia 8 spp. native to all of Mexico, inc. 5 narrow endemics; Vinca 1 sp. intro to SW+C+SE Mexico.
Neotropical ApocynaceaeGenera
Apocynoideae in the Neotropics
Allomarkgrafia 10 spp. neoendemic genus of Honduras S to Colombia, Ecuador, and Peru; Anodendron 1 sp. intro to Trinidad-Tobago; Asketanthera 4 spp. Greater Antilles endemic genus of Cuba, the Dominican Republic, and Haiti; Bahiella 2 spp. narrow endemic genus of NE Brazil; Beaumontia 1 sp. intro to Costa Rica, Guatemala, El Salvador, and Honduras; Echites 13 spp. native to CAM, the Bahamas, Turks-Caicos, the Greater Antilles, and the Leeward Islands, including 4 narrow endemics of Cuba (2), Costa Rica (1), and Panama (1); Forsteronia 45 spp. neoendemic genus of Cuba, Jamaica, Trinidad-Tobago, CAM, and tropical SAM S to N Argentina (exc. N Chile); Funtumia 1 sp. intro to Cuba, Puerto Rico, Trinidad-Tobago, and El Salvador; Galactophora 6 SAM endemic spp. of Colombia, N+C Brazil, Venezuela, Guyana, Peru, and Bolivia; Hylaea 2 spp. N SAM endemic genus of S Venezuela and N Brazil; Laubertia 3 spp. neoendemic genus of Belize (1 endemic), Colombia, Venezuela, N Brazil (1 endemic), Ecuador, Peru, and Bolivia; Macropharynx 15 neoendemic spp. of Honduras, Costa Rica, Panama, Colombia, Venezuela, Guyana, Suriname, Ecuador, Peru, Bolivia, Paraguay, Brazil, and N Argentina; Malouetia ~20 spp. native to CAM (exc. El Salvador), Windward Is, Colombia, Venezuela, French Guiana, Suriname, Guyana, Brazil (exc. C Brazil), Peru, and Bolivia, and intro to Cuba; Mandevilla ~165 spp. mostly neoendemic genus native to CAM, Cuba, Jamaica, Trinidad-Tobago, and tropical SAM S to N Argentina (exc. N Chile); Mesechites 8 spp. mostly neoendemic genus native to CAM, Cuba (2 endemics), Hispaniola (1 endemic), Jamaica, Trinidad-Tobago, and tropical SAM S to N Argentina (excluding Uruguay and N Chile); Neobracea 8 spp. narrow single-island endemics of Cuba (7) and Cuba + the Bahamas (1); Nerium monospecific sp. intro to CAM and S Brazil; Odontadenia 23 spp. neoendemic genus native to CAM (exc. El Salvador), Hispaniola, Colombia, N+E+C Brazil, Venezuela, Guyana, Suriname, French Guiana, Ecuador, Peru, Bolivia, and Trinidad-Tobago and intro to the Windward Is.; Pentalinon 2 spp. native to the Bahamas, Turks & Caicos, Greater Antilles, SW Caribbean, Leeward & Windward Is., Guatemala, Belize, El Salvador, Honduras, and Nicaragua; Pinochia 4 spp. mostly N neoendemic genus native to Guatemala, Belize, Nicaragua, Costa Rica, Panama, and the Greater Antilles (exc. Cayman Is. & inc. 2 endemics); Prestonia 63 spp. Mexico & neoendemic genus native to CAM, tropical SAM S to N Argentina (exc. N Chile), Leeward & Windward Is., and Trinidad-Tobago; Rhabdadenia 3 spp. native to CAM, Bahamas, Greater Antilles, Leeward & Windward Is., Trinidad-Tobago, and tropical SAM S to N Argentina (exc. N Chile); Rhodocalyx 2 spp. SAM endemic genus of Peru, Bolivia, C+E+S Brazil, Paraguay, and N Argentina; Salpinctes monospecific endemic of S Colombia; Stipecoma monospecific SAM endemic of Bolivia and C+E Brazil; Strophanthus 1 sp. intro to Trinidad-Tobago; Temnadenia 2 spp. endemic genera of Brazil (exc. N); Thenardia 1 S Mexico + Honduras endemic sp. native to Honduras; Tintinnabularia 2 spp. Mesoamerica endemic genus native to Guatemala and Honduras (1 endemic).
Asclepiadoideae in the Neotropics
Anechites monospecific N neoendemic genus of Honduras S to Colombia, Venezuela, Ecuador, and Peru, plus the Greater Antilles; Anemotrochus 3 spp. Caribbean endemic genus of the Bahamas, Turks-Caicos, Cuba, Hispaniola, and Jamaica; Araujia 13 spp. former S SAM endemic genus native Bolivia, C+SE+S Brazil, Paraguay, Uruguay, and Argentina, and intro in C Chile; Asclepias 12 spp. native to CAM, Bahamas, Turks-Caicos, Antilles (exc. Aruba), Trinidad-Tobago, Galapagos, and most of SAM, exc. Chile and intro in N Chile; Barjonia 7 spp. SAM endemic genus of Brazil, Suriname, and Bolivia; Blepharodon 4 spp. SAM endemic genus native to Bolivia, C+S+SE Brazil, NE Argentina, and Paraguay; Calotropis 2 spp. intro to Bahamas, Turks and Caicos, Antilles, Trinidad-Tobago, Colombia, Venezuela, N+C+E Brazil, Paraguay, and Bolivia; Cristobalia 2 spp. native to Bolivia, Uruguay, N Argentina, and S Brazil; Cynanchum ~15 spp. native in CAM, Cuba, Jamaica, tropical SAM S to N Argentina (exc. N Chile); Diplolepis 9 spp. S SAM endemic genus native to N+C Chile, NW Argentina, including 4 narrow endemics of Chile, the rest in Patagonia; Ditassa 114 SAM endemic spp. of Colombia S to N Argentina, except N Chile and Paraguay; Fischeria 17 spp. neoendemic genus native from S Mexico S through CAM (exc. El Salvador), Cuba, Jamaica, Trinidad-Tobago, Colombia, Venezuela, Ecuador, Peru, Bolivia, Brazil, Paraguay, and NE Argentina; Funastrum 12+ spp. native to the Antilles (exc. Aruba, Leeward, Netherlands Antilles), Trinidad-Tobago, CAM, and tropical SAM S to N Argentina (exc. N Chile), including 5 narrow endemics of Guatemala, Bolivia, Colombia, SE Brazil, and Galapagos; Gomphocarpus 1 sp. intro to CAM (exc. Belize), Cuba, Jamaica, Puerto Rico, Leeward Is, Colombia, Venezuela, Suriname, Brazil, Uruguay, NE Argentina, Ecuador, Peru, and Bolivia; Gonolobus ~100 spp. native to Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., CAM, and tropical SAM S to N Argentina (exc. N Chile, Suriname, French Guiana); Gyrostelma monospecific endemic of C+SE Brazil; Hemipogon 8 spp. SAM endemic genus of Peru, Brazil, Bolivia, and Paraguay; Hoya 1 sp. intro to Cuba, Trinidad-Tobago, Puerto Rico, and Leeward Is.; Hypolobus monospecific endemic of NE Brazil; Ibatia 36 spp. neoendemic genus of Honduras, Nicaragua, Panama, Cuba, Hispaniola, Puerto Rico, Lesser Antilles, Colombia, Venezuela, Guyana, Brazil, Paraguay, Ecuador, Bolivia, and N Argentina; Jobinia 25 spp. neoendemic genus native to Guatemala, Honduras, Venezuela, Ecuador, Peru, Bolivia, C+S+E Brazil, N Argentina, and Uruguay; Lachnostoma 16 spp. N SAM endemic genus of Colombia, Ecuador, Peru, and Venezuela; Macroscepis 19 spp. Mexico & neoendemic genus native to CAM (exc. Belize), Colombia, Venezuela, Guyana, Ecuador, Peru, Bolivia, Paraguay, N Argentina, and Brazil; Matelea ~140 spp. native to CAM, Bahamas, Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., Trinidad-Tobago, and tropical SAM S to N Argentina (exc. N Chile); Metastelma ~85-90 spp. native to the Bahamas, Turks and Caicos, Antilles, CAM, Colombia, Venezuela, Guyana, N+E+S Brazil, Ecuador, Peru, Bolivia, Paraguay, and N Argentina; Minaria 22 spp. SAM endemic genus of Brazil, Bolivia, and NE Argentina; Monsanima 2 spp. narrow endemic genus of E Brazil; Nautonia monospecific E SAM endemic genus of C+SE+S Brazil, Paraguay, and NE Argentina; Nephradenia 5 spp. N SAM endemic genus of Colombia, Venezuela, Guyana, N+E+C Brazil, and Bolivia; Orthosia ~48 spp. neoendemic genus native to CAM (exc. Belize), Colombia, Venezuela, E+S Brazil, Uruguay, N Argentina, Ecuador, Peru, Bolivia, Paraguay, Bahamas, and the Greater Antilles (exc. Cayman Is); Oxypetalum 139 spp. mostly neoendemic genus of Guatemala, Honduras, Costa Rica, Panama, Greater Antilles (exc. Cayman Is), Leeward Is, Colombia, Venezuela, Guyana, Brazil, Ecuador, Peru, Bolivia, Paraguay, Uruguay, and N Argentina; Pentacyphus 3 spp. N SAM endemic genus of high Andean Venezuela, Colombia, Ecuador, and Peru, including 1 narrow endemic of Caldas, Colombia; Peplonia 9 spp. SAM endemic genus of Peru, Bolivia, E+C+S Brazil, and Paraguay; Petalostelma 7 spp. SAM endemic genus of Brazil, Bolivia, Paraguay, and N Argentina; Pherotrichis 1 sp. native to Guatemala; Philibertia 41 spp. SAM endemic genus of Ecuador, Peru, Bolivia, N+C Chile, and Argentina; Pseudolachnostoma 12 spp. neoendemic genus of Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, Venezuela, N Brazil, and Trinidad-Tobago; Rhytidostemma 8 spp. neoendemic genus of Panama, Colombia, Venezuela, Guyana, Suriname, French Guiana, C+N Brazil, Ecuador, and Peru; Rojasia monospecific SAM endemic genus of Bolivia, Paraguay, S Brazil, and NE Argentina; Ruehssia ~120+ spp. Mexico & neoendemic genus native to CAM, much of the Antilles, and tropical SAM S to N Argentina (exc. N Chile); Schubertia 6 spp. SAM endemic genus of Colombia, Peru, Bolivia, Paraguay, Brazil, and N Argentina; Scyphostelma 39 spp. neoendemic genus of Costa Rica, Panama, Colombia, Venezuela, Ecuador, Peru, and Bolivia; Stephanotis 1 sp. intro to Cuba, Hispaniola, Puerto Rico, Leeward Is., and Trinidad-Tobago; Tassadia 31 spp. neoendemic genus native to S Mexico, Cuba, Trinidad-Tobago, Belize, Nicaragua, Costa Rica, Panama, and tropical SAM S to Peru, Bolivia, Paraguay, and S Brazil; Topea 2 spp. narrow endemic genus of WC Brazil, Paraguay, and NE Argentina; Tweedia 6 spp. S SAM endemic genus of Bolivia, N+C Chile, Argentina, and Paraguay, with most being narrow endemics; Tylodontia 4 spp. narrow endemic genus of Cuba.
Periplocoideae in the Neotropics
Cryptostegia 2 spp. intro to CAM (exc. Guatemala, Belize), the Bahamas, the Antilles, Trinidad-Tobago, Colombia, Venezuela, and N+NE+C Brazil.
Rauvolfioideae in the Neotropics
Allamanda 15 spp. of former neoendemic genera native to tropical SAM S to Bolivia, NE Argentina, and S Brazil, excluding Ecuador and Paraguay and intro to Honduras, Nicaragua, Costa Rica, Panama, Guatemala, Belize, El Salvador, Trinidad-Tobago, and Galapagos; Alstonia 1 sp. native to CAM (exc. Belize) and intro in Trinidad-Tobago; Ambelania 3 spp. SAM endemic genus of Colombia, Venezuela, Peru, N+NE Brazil, French Guiana, Guyana, and Suriname; Anechites monospecific N neoendemic of Honduras S to Colombia, Venezuela, Ecuador, and Peru, and the Greater Antilles (exc. Cayman Is.); Aspidosperma ~78 spp. neoendemic genus native from S Mexico S through CAM and tropical SAM S to N Argentina (except N Chile), Hispaniola, Trinidad-Tobago, and the Venezuelan Antilles; Cameraria 7 spp. native to Belize, Guatemala, Cuba (4 endemics), Hispaniola (2 endemics), Jamaica, and the Greater Antilles; Carissa 1 sp. intro to Honduras, Nicaragua, Bahamas, Jamaica, Puerto Rico, Leeward & Windward Is, and Trinidad-Tobago; Cascabela 3 spp. native CAM S through tropical SAM to Peru, Bolivia, NE Argentina, SE Brazil (exc. NE Brazil), and intro to Bermuda, Bahamas, Antilles (exc. Cayman Is., Netherlands Antilles); Catharanthus 1 sp. intro to CAM, Bahamas, Turks-Caicos, Antilles (exc. Cayman Is., Venezuelan Antilles), SW Caribbean, the Galapagos, and French Guiana; Cerbera 1 sp. intro to Trinidad-Tobago; Chamaeclitandra monospecific intro to Trinidad-Tobago; Condylocarpon 7 spp. neoendemic genus of Nicaragua, Costa Rica, Colombia, Venezuela, Brazil, French Guiana, Guyana, Suriname, Paraguay, Peru, Uruguay, NE Argentina, and Trinidad-Tobago; Couma 5 spp. neoendemic genus of Guatemala, Belize, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Venezuela, Suriname, Guyana, French Guiana, N+NE Brazil, Ecuador, Peru, and Bolivia; Geissospermum 5 spp. SAM endemic genus of Venezuela, Guyana, Suriname, French Guiana, N+E Brazil, Peru, and Bolivia; Hancornia monospecific SAM endemic genus of Bolivia, Brazil, Paraguay, and Peru; Haplophyton 2 spp. native to Guatemala and introduced in Cuba; Himatanthus 9 spp. neoendemic genus of Panama and tropical SAM S to Peru, Bolivia, and C+SE Brazil; Kopsia 1 sp. intro to Trinidad-Tobago; Lacmellea 24 spp. neoendemic genus native to CAM (exc. El Salvador), and tropical SAM S. to Peru, Bolivia, and C+E Brazil; Landolphia 1 sp. intro to Trinidad-Tobago; Laxoplumeria 5 spp. neoendemic genus of Panama, Colombia, Ecuador, Peru, Bolivia, Brazil, and French Guiana; Macoubea 3 spp. neoendemic genus of Costa Rica, Panama, Colombia, Peru, Bolivia, Venezuela, Guyana, Suriname, French Guiana, and N+NE Brazil; Microplumeria monospecific N SAM endemic genus of Colombia, Venezuela, and N Brazil; Molongum 3 spp. N SAM endemic genus of Colombia, Venezuela, and N Brazil; Mortoniella monospecific CAM endemic to Belize, Nicaragua, and Costa Rica; Mucoa 2 spp. N SAM endemic genus of Colombia, Venezuela, N Brazil, and Peru; Neocouma 2 spp. N SAM endemic genus of Colombia, Venezuela, Peru, and N Brazil; Pacouria 3 spp. N SAM endemic genus of Colombia, Venezuela, Guyana, Suriname, French Guiana, N+SE Brazil, Bolivia, and Peru; Parahancornia 7 spp. NW SAM endemic genus of Colombia, Venezuela, Guyana, Suriname, French Guiana, N Brazil, Peru, and Bolivia; Plumeria 18 spp. native to CAM, Colombia, Venezuela, Guyana, Bahamas, Turks-Caicos, Antilles (exc. Aruba, Netherlands Antilles), and SW Caribbean and now intro to Ecuador, Peru, Bolivia, Paraguay, Netherlands Antilles, and Trinidad-Tobago; Rauvolfia ~25 spp. native to CAM, Antilles (exc. Netherlands Antilles), tropical SAM S to N Argentina (exc. Uruguay, N Chile); Rhigospira monospecific N SAM endemic genus of Colombia, Venezuela, N Brazil, and Peru; Skytanthus 3 spp. narrow SAM endemic genus of E Brazil (2), N+C Chile (1); Spongiosperma 6 spp. N SAM endemic genus of Colombia, Venezuela, and N+NE Brazil; Strempeliopsis 2 spp. single island endemic genus of Cuba (1) and W Jamaica (1); Tabernaemontana ~45 spp. native to the Antilles (exc. Aruba, Netherlands Antilles), SW Caribbean, tropical SAM S to Peru, Bolivia, and NE Argentina; Thevetia 3 spp. Mexico & neoendemic genus native to CAM, Cuba, Colombia, Venezuela, N & C Brazil, Bolivia, Paraguay, and NE Argentina; Vallesia 6 spp. native to Cuba, Hispaniola, Jamaica, Belize, Guatemala, El Salvador, Honduras, Costa Rica, Colombia, Venezuela (1 endemic), N Brazil, Peru, Bolivia, Paraguay, N Argentina, and Galapagos (1 endemic); Vinca 2 spp. intro to Guatemala, Costa Rica, Colombia, Venezuela, Bolivia, C Chile, and Uruguay.
Patagonia ApocynaceaeGenera
Apocynoideae in Patagonia
Elytropus monospecific endemic to C & S Chile and S Argentina.
Asclepiadoideae in Patagonia
Araujia 1 sp native to S Argentina; Asclepias 1 sp. native to S Argentina; Diplolepis 10 spp. S SAM endemic genus native to SC+S Chile and S Argentina, including 5 narrow endemics; Philibertia 1 sp. SAM endemic genus native to C Chile and S Argentina; Tweedia 2 spp. S SAM endemic genus native to C Chile and S Argentina.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, as well as my own personal observations.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Endress, Mary & Liede-Schumann, Sigrid & Meve, Ulrich. (2014). An updated classification for Apocynaceae. Phytotaxa. 159. 10.5167/uzh-93115.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
Stevens, P. F. (2001 onwards). Angiosperm Phylogeny Website. Version 14, July 2017 [more or less continuously updated since]. http://www.mobot.org/MOBOT/research/APweb/
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout the fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
9 Oct, 2022
28 Sep, 2022
How to Identify the Aristolochiaceae or Birthwort Family
Aristolochia taliscana flower showing unusual hairs used to temporarily trap flies for pollination. Page Last Updated August 19, 2026.
Introduction to the Aristolochiaceae or Birthwort Family
The Aristolochiaceae are a family with bizarre-looking flowers, and each genus has its own unique and often very bizarre morphology. Since I always believe the weirder the better, the first time I saw an Asarum and an Aristolochia, I was instantly in love with their unique beauty.
And the bizarre got even more bizarre when the Angiosperm Phylogeny Group (IV) recently combined two very small families into the Aristolochiaceae so that it would not be paraphyletic. Since these new subfamilies are themselves very unique and different morphologically from the traditional Aristolochiaceae (which only included Asaroideae and Aristolochioideae), I am describing the subfamilies separately from the traditional Aristolochiaceae.
Beginners Guide to the Birthwort (Arisolochiaceae) Family
If you’re new to plant morphology, this guide is a perfect beginner’s description to help you learn how to identify the Aristolochiaceae family, with no need to know any scientific jargon. Below this are morphology photos and pictures of some species found in North America to further help you with identification. But for researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below the images in addition to genus-level distribution data.
Leaves and Stems of the Birthwort Family
These are mostly woody vines, shrubs, or herbs with simple (never compound) leaves on stalks (petioles) that are usually arranged in a spiral pattern and are often heart-shaped (cordate) or kidney-shaped (reniform). Most have aromatic leaves that may have gland dots. The Hydnoroideae are leafless parasitic herbs that live almost entirely below the soil.
Flowers of the Birthwort Family
The flowers are unusual and highly characteristic of the family, often known for their S-shaped floral tubes, but they are also highly variable. They are very small to often large and showy and often emit strong, foul odors. They also often have unique and specialized hairs designed to trap flies. They are held there until the hairs wither, releasing them to escape and pollinate other flowers.
Reproductive Features of the Birthwort Family
The reproductive features are highly variable in the family, but they typically have 3-36 stamens, which are often fused to the female parts into a specialized central column called a gynostegium but are also often free. The ovary may be inferior (attached below the point of attachment of the floral parts) or superior (attached above the floral parts).
Fruits of the Birthwort Family
Fruits are mostly dry capsules that split open when ripe to release their seeds. They may sometimes be a fleshy berry-like fruit.
Morphology of Aristolochiaceae in North America
Some Species of Aristolochiaceae Found in North America
Aristolochioideae Subfamily
Aristolochia taliscana – Mexican Birthwort
This is a lush medium green vine with heart-shaped (cordate) leaves with a deep cleft and a rounded to notched tip. Flowers are solitary in leaf axils with an S-shaped petal-like calyx in burgundy, purple, or brown, usually with yellow markings. The limb is covered with conspicuous purple hairs that trap pollinating insects. Native to western Mexico.
Aristolochia watsonii – Watson’s Dutchman’s Pipe
This one has very deeply arrow-shaped (sagittate) green leaves with purple markings. The calyx tube is straight or S-shaped, and the limb has maroon spots and no elaborate hairs. It is native to the southwestern USA and northwestern Mexico.
Asaroideae Subfamily
Asarum caudatum – Western Wild Ginger
This long favorite of mine has classic heart-shaped leaves with very long stalks from the ground (no plant stem). Flowers are solitary and burgundy or greenish-yellow, with a 3-part calyx with very long lobes that taper to a fine point. It is native to the Pacific Northwest, from BC, Canada, south to California, and east to Idaho and Montana, USA.
Asarum (Hexastylis) arifolia Little Brown Jug
This low herbaceous perennial has triangular, arrow-shaped, heart-shaped, or diamond-shaped leaves that are often variegated (this one shows slight variegation). Flowers are jug-shaped (urceolate) and brown, purple, or reddish with three lobes that may or may not be flared (visible at the base of the leaf stalk). Native to the southeastern USA.
This one has round to heart-shaped & usually variegated leaves. Its flowers are similar to A. arifolia but much larger. It’s a narrow endemic of the southern Appalachians & the surrounding area, eastern USA.
Uses of the Aristolochiaceae Family
Several species of Aristolochia (e.g., A. grandiflora, A. gigantea, A. littoralis) are cultivated globally as ornamental greenhouse and garden vines for their bizarre, showy perianths. Many Asarum (Hexastylis) species are grown as shade-tolerant, evergreen groundcovers.
While many were used in traditional medicine, they are no longer recommended since Aristolochia and some Asarum contain a toxin known to be carcinogenic to humans and rats. However, historically, the fruits of the Hydnoroideae were collected, roasted, and eaten by indigenous human populations.
Ecosystem and Wildlife Values of the Aristolochiaceae Family
Caterpillars, including the pipevine swallowtail, Battus philenor, and tropical birdwing butterflies, are specialized herbivores on Aristolochia. Rather than succumbing to the toxins, larvae sequester aristolochic acids within their bodies, rendering both the caterpillars and adult butterflies unpalatable to birds and other predators.
The fleshy, geocarpic, baccate fruits of Hydnora (commonly known as “jackal food” in southern Africa) develop a fragrant, astringent-to-sweet pulp packed with starch and tannins. They serve as an important food source for mammals like baboons, jackals, porcupines, and rhinos.
Taxonomy of Aristolochiaceae
The Aristolochiaceae family has 682 species in 7-9 genera of the Piperales order in the Magnoliids clade of mesangiosperms. This clade is technically not part of either the monocots or the dicots but instead is one of the sister groups to monocots and dicots, having diverged early on.
APG IV (2016) has combined the former Hydnoraceae and Lactoridaceae, as their exclusion would render the Aristolochiaceae paraphyletic. Molecular phylogenies have confirmed that Lactoris and the holoparasitic hydnoras are nested deeply within the traditional aristolochioid lineage.
Aristolochioideae Subfamily
Plants are mostly lianas, but occasionally shrubs or herbs. Inflorescences are usually axillary, and the flowers, or at least the floral buds, are zygomorphic, though Thottea is actinomorphic or weakly zygomorphic. The gynoecium has 4-6(2-3) carpels, which are constricted apically. One of the defining synapomorphies is the stamens, which in Aristolochia (6, rarely 4-5 stamens) are fused with the style into a 3- to 6-lobed gynostemium, while in Thottea the 6-40 stamens are arranged in whorls around the lower part of a multi-lobed style column. Stigmas are wet or dry and are commissural in Aristolochia. Fruits are mostly 6-locular dehiscent capsules that dehisce septicidally, but Thottea forms 4-angled, 4-valved siliquiforms, and Pararistolochia (if separated from Aristolochia) forms indehiscent baccate fruits.
Aristolochia (569 s.l.), Thottea (46).
Asaroideae Subfamily
Plants are rhizomatous perennial herbs with actinomorphic and trimerous flowers that are solitary and terminal. Flowers mostly are apetalous, made of 3 connate sepals forming a fleshy calyx tube, but have 3 distinct sepals and petals in Saruma. The gynoecium is inferior or half-inferior, and the stigma has multicellular papillae, and a key defining feature is that unlike the Aristolochioideae, the stamens are distinct or only weakly adnate to the style column and do not form a gynostemium. The fruit of the Asarum is an irregularly dehiscent capsule and a follicular schizocarp in Saruma.
Asarum (138 s.l.), Saruma (1).
Hydnoroideae Subfamily
Unusual obligate root holoparasitic herbs that resemble fungi with warted, cylindrical haustorial roots that make contact with host roots. The plants lack leaves, stems, and chlorophyll and live mostly underground with only fleshy, foul-smelling flowers emerging above the soil.
Hydnora (10), Prosopanche (7).
Lactoridoideae Subfamily
The Lactoridoideae is a monospecific subfamily consisting of a narrowly endemic plant found only in the cloud forests of Robinson Crusoe Island (Juan Fernández Archipelago, Chile). It is a small, glabrous perennial subshrub with small alternate leaves prominently dotted with pellucid oil cells, with very small flowers and dry fruits that split into pod-like segments.
Lactoris monospecific (Lactoris fernandeziana).
Key Differences From Similar Families
The unique flowers of most members of the Aristolochiaceae make them difficult to confuse with other families. The subfamilies Aristolochioideae and Asaroideae are so unique that they are rarely confused with other families, and the Lactoridoideae is a rare microendemic from the Juan Fernández Islands. Still, the Piperaceae is a sister lineage within Piperales, and climbing species share cordate/palmate-veined alternate leaves, swollen nodes, and aromatic pellucid oil cells, but the Piperaceae differs by bearing spicate, minute, ebracteate flowers lacking a perianth, whereas the Aristolochiaceae bears large, showy, synsepalous perianths.
The Balanophoraceae are often confused with Hydnoroideae due to the leafless, achlorophyllous root-holoparasite habit and fungus-like subterranean emergence. However, the Balanophoraceae differ by their dense, club-like inflorescences with hundreds of minute unisexual flowers, compared to the solitary, massive, 3–4-merous trap flowers in the Hydnoroideae.
The Orobanchaceae are the most common root-parasite family that produces fleshy, leafless/scaly flowering stems, but the Orobanchaceae flowers are sympetalous, bilabiate corollas arranged in erect racemes or spikes with superior ovaries and four didynamous stamens.
Scientific Botanical Description of the Aristolochiaceae
Note that, with the addition of the two very unique subfamilies, I have combined the Lacoridoideae in the traditional Aristolochiaceae description since they share many features but added descriptions of the Hydnoroideae separately simply because they are so different from the rest.
Habit & Leaf Form of Aristolochiaceae
Most Aristolochiaceae are perennial lianas, twiners, rhizomatous herbs, or small shrubs bearing essential oils. Most plants are mesophytic, except the xerophytic Hydnoroideae.
Leaves are simple, alternate, spiral (distichous in Lactoridoideae), flat, and either herbaceous or herbaceous and membranous. They are petiolate, non-sheathing (sheathing in Lactoridoideae), simple, aromatic, and may be gland-dotted, pellucid, or punctate.
The lamina is usually entire or sometimes dissected, palmatifid, or trilobed and is often cordate, reniform, or auriculate. They are either palmately or pinnately veined and are cross-venulate. Leaves are mostly exstipulate, except in the Lactoridoideae, which possess intrapetiolar stipules, and occasionally the first 1–2 leaves of suppressed branches simulate stipules in Aristolochia.
The Hydnoroideae are holoparasitic herbs with a very peculiar vegetative form that lacks leaves, stems, and chlorophyll. The vegetative component consists of a coarse, rhizome-like pilot root with many slender, unbranched haustorial roots that parasitize the roots of host plants.
Flowers of Aristolochiaceae
Plants are hermaphrodites or polygamomonoecious to gynomonoecious in Lactoridoideae. Pollination in Aristolochia is entomophilous and occurs via Diptera, with a conspicuously specialized mechanism that uses articulated hairs to trap flies within the perianth tube; these hairs wither to release the flies, allowing them to visit another flower. In Asaraoideae, pollination is often via fungus gnats or beetles; in Hydnoroideae, it is exclusively pollinated by carrion beetles, and the Lactoridoideae are primarily anemophilous.
Flowers can be solitary or aggregated in axillary or occasionally terminal cymes, racemes, or spikes. Flowers are very unusual in shape and can be minimal to very large. They are often malodorous and smelling of carrion but may also be odorless. They are actinomorphic to zygomorphic (Aristolochia) and tricyclic to pentacyclic.
The perianth usually has parts joined in one whorl, which is often petaline, with 3 sepals connated into a campanulate, rotate, or tubular-inflated structure. In Aristolochia, the tubular perianth is differentiated into an inflated basal chamber (utricle), a narrowed cylindrical tube (often S-shaped or bent), and a 1–3-lobed, expanded, uniseriate limb. However, in the Lactoridoideae, the perianth is small and sepaline. Only in Saruma and select Asarum is the corolla whorl conspicuous and well developed.
The Hydnoroideae are hermaphrodites, and pollination is via beetles. Flowers are solitary and arise endogenously from the pilot roots on short stalks that barely emerge above the ground. They are medium to large, malodorous, regular, and either tricyclic or tetracyclic with a short free hypanthium. The perianth is sepaline or petaline with 3–4 (5) parts joined in one whorl with valvate lobes that are often fleshy with retrorse bristles used as temporary traps.
Androecium of Aristolochiaceae
The androecium has 3–36 members in one or two whorls (always 2 in Lactoridoideae) that are free of the perianth and free of the gynoecium (always in Lactoridoideae) or, more often, united with the gynoecium, forming a gynostemium. All members are usually fertile (may contain staminodes in Lactoridoideae), usually with 5-6(4) stamens in Aristolochioideae, 6 in Lactoridoideae, 12 in Asaroideae, or 3-4(5) in Hydnoroideae.
Members are mostly fertile, but staminodes are sometimes present in Prosopanche and Lactoris.
Stamens usually have short filaments, but they can be well-developed in Asaroideae and are typically absent in Hydnoroideae.
Anthers are usually separate from one another but connate into a massive, sessile, fleshy synandrium in Hydnora and some Prosopanche. Anthers are 2-locular (tetrasporangiate), usually extrorse, basifixed, and dehiscing by longitudinal lateral slits but may also be irregular or transverse slits in Hydnoroideae. Anthers are sometimes appendaged apically with the expanded connective, but they may also be unappendaged.
Gynoecium of Aristolochiaceae
The gynoecium is highly variable, depending on the subfamily.
In the Aristolochioideae, there are 6 (sometimes 4–5) syncarpous carpels with an inferior ovary that is typically 6-locular with axile placentation (or 1-locular with deeply intruded parietal placentas in Thottea). The style column is fused with the stamens into a gynostemium, terminating in (3)6 fleshy, commissural, stigmatic lobes. There are 20-100+ ovules per locule, anatropous, bitegmic, crassinucellate, horizontal to pendulous with a distinct funicle.
In the Asaroideae there are 6 syncarpous carpels with an inferior to half-inferior (superior/half-inferior in Saruma) ovary that is 6-locular with axile placentation or 1-locular with intrusive parietal placentas. There are 6 free or basally connate styles tipped with decurrent or capitate stigmas covered with multicellular papillae. Ovules are numerous, anatropous, and bitegmic.
In the Lactoroideae, there are 3 apocarpous carpels arranged in a single whorl, with a superior ovary. The stigmas are sessile and decurrent along the adaxial suture of each free carpel. Placentation is marginal/ventral; ovules are 4–8 per carpel, anatropous, bitegmic, and crassinucellate.
In the Hydnoroideae, carpels are 3–4(5) and syncarpous with a strictly inferior, unilocular ovary, but the cavity is often heavily occluded by massively expanded, intruding lamellate placentas. Placentation is parietal (in Prosopanche) or apical/pendulous (in Hydnora). The stigma is cushion-like, 3-lobed, and sessile directly on the ovary tip/hypanthium floor. Ovules are extremely numerous (thousands to hundreds of thousands), minute, orthotropous to hemianatropous, and unitegmic.
Fruit of Aristolochiaceae
The fruits, like the gynoecium, are very diverse morphologically.
In the Aristolochioideae, the fruits are mostly dry, 6-valved, septicidally dehiscent capsules opening basipetally (forming a hanging basket in pendulous species) or acropetally; elongated and siliquiform in Thottea; or an indehiscent, elongated berry-like fruit in Aristolochia subg. Pararistolochia. Seeds are numerous with copious endosperm, oily, sometimes weakly ruminate, and may be winged or not.
In the Asaroideae, the fruit is an irregularly bursting, fleshy to leathery subglobose capsule in Asarum (often dehiscing irregularly upon decomposition in leaf litter) or a follicular schizocarp splitting into 6 dry, dehiscent, follicle-like mericarps in Saruma. Seeds unwinged, obovoid to oblong, smooth to rugose, bearing a prominent, fleshy lateral elaiosome/caruncle for ant dispersal. The endosperm is copious, oily, and non-ruminate.
In the Lactoroideae, the fruit is an aggregate of 3 free, beaked, dry follicles that dehisc along their adaxial (ventral) sutures. Seeds are 4–8 per follicle, small, ovoid, ribbed, unwinged, and lacking an aril. The endosperm is copious and oily.
The Hydnoroideae is a large, globose to subglobose, geocarpic (subterranean) baccate fruit with a thick, scaly or leathery/woody pericarp (subterranean and indehiscent or splitting irregularly in Hydnora; circumscissile near the apex in Prosopanche), containing tens of thousands of minute, globose, hard-coated seeds. Seeds possess both a hard outer seed coat and rich perisperm and endosperm.
Global Distribution of Aristolochiaceae
The traditional Aristolochiaceae family is widespread in warm temperate to tropical areas around the world except in Australasia, and they are not present in arctic areas. Thy Hydnoroideae are mostly found in South America and Africa, while the Lactoridoideae is a rare microendemic genus confined to Juan Fernández Island off the coast of Chile.
Distribution of Aristolochiaceae in the Americas
Canadian AristolochiaceaeGenera
Aristolochioideae:Aristolochia 2 spp. including 1 native to ON and 1 intro (sometimes referred to as Isotrema) to ON and QC.
Asaroideae:Asarum 2 spp. native to BC, MB, ON, QB, and NB.
USA AristolochiaceaeGenera
Aristolochioideae: Aristolochia 16 spp., mostly native, some intro to most of the USA except WA, OR, NV, UT, ID, MT, WY, CO, ND, SD, NE, MN, and VT.
Asaroideae:Asarum (inc. Hexastylis) 17 spp. native in most of the USA except NV, AZ, UT, WY, CO, NM, NE, and TX.
Mexico AristolochiaceaeGenera
Aristolochioideae: Aristolochia 47 spp. native throughout all of Mexico, including the Mexican Pacific Islands.
Asaroideae: Asarum 1 sp. native Yuc.
Neotropical AristolochiaceaeGenera
Aristolochioideae: Aristolochia ~200 spp. native throughout Mexico, CAM, Bermuda, the Bahamas, Cuba, Hispaniola, Jamaica, Puerto Rico, the Leeward & Windward Is., and tropical SAM S to Santiago, C Chile, and N Argentina, and it is intro in the Venezuelan Antilles and Galapagos.
Hydnoroideae: Prosopanche 7 neoendemic spp. native to Costa Rica, Peru, Bolivia, Argentina, Paraguay, NE & S Brazil.
Lactoridoideae:Lactoris monospecific endemic of Juan Fernandez Island off the coast of Chile.
Patagonia AristolochiaceaeGenera
Hydnoroideae: Prosopanche 1 sp. native to S. Argentina.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, as well as my own personal observations.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Flora of North America. (1993+). https://floranorthamerica.org/Main_Page
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009 onwards). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
28 Sep, 2022
25 Sep, 2022
How to Identify the Amaranthaceae or Amaranth Family
Amaranthus palmeri inflorescence showing tiny flowers in bloom. Page last updated August 18, 2026.
Introduction to the Amaranthaceae Family
The Amaranthaceae family is part of the Caryophyllales order of core eudicots (dicots), made of mostly herbs or shrubs that are often found growing in disturbed habitats, making them often very weedy. However, many edible plants come from the Amaranthaceae, including commercially important ones.
Still, most of us will recognize this maligned family as weeds, often noxious ones, like certain Amaranth, Salsola, Iresine, and Bassia, to name just a few. They are hardy herbs or sub-shrubs that can grow in deserts, saline or alkaline soils, and extreme heat.
I have always thought that instead of waging war on amaranth with glyphosate (to which most are now resistant, which is why we have “Roundup Ready” crops so they can still kill the amaranth without killing the crops), we should grow it and eat it instead. It will grow in marginal lands already badly degraded by conventional farming (chemicals and tilling), and it needs very little water and very little fertilizer. You can also harvest about 60-80% of the leaves (eat them like spinach; they are delicious!) without it impacting seed production. Seeds can be eaten in porridge or ground into a gluten-free flour for baking with (mmm… zucchini bread and carrot cake). It is far more nutritious than the corn and wheat fields it competes with. Lesson: EAT THE WEEDS instead of poisoning ourselves trying to kill them!
Beginner’s Guide to the Amaranth (Amaranthaceae) Family
If you’re new to plant morphology, this guide is a perfect beginner’s description to teach you how to identify the Amaranth (Amaranthaceae) family, with no need to know any scientific jargon. Below is additional information on uses and morphology, as well as pictures to help identify family members and individual species found in North America.
But for researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below the images in addition to genus-level distribution data.
Leaves and Stemsof the Amaranth Family
Most members are annual or perennial herbs or shrubs, sometimes described as sub-shrubs due to their somewhat woody nature. Stems often have thickened joints (nodes) and may become fleshy (succulent) in some species. Leaves vary in size from tiny scales to large, well-developed leaves but are also occasionally absent. Leaves are usually simple (not compound) and may be in opposite pairs or alternately arranged along the stem.
Flowersof the Amaranth Family
Flowers are usually very small to minute and grow in spikes, heads, tight clusters, or branched groups. They are most often accompanied by conspicuous papery leaf-like structures (bracts) that stay on the plant for a long time. Rather than petals, most flowers are made of thin and papery tepals that look more like scales or sepals, and they sometimes remain attached to the fruits as they grow, developing into wings, spines, or bumps to help protect or distribute them.
Reproductive Featuresof the Amaranth Family
These are very diverse in the family, ranging from flowers with both male and female parts (bisexual) to separate male and female flowers on separate plants (dioecious). And since the flowers are tiny, these features are seldom easily visible, so we’ll skip it here. But you can check out the scientific botanical description below for more information.
Fruitsof the Amaranth Family
Fruits may be dry, bladder-like fruits (utricles) or capsules that may split open from the top, but occasionally they are small, fleshy berry-like fruits. In many species, the fruit stays enclosed in and is dispersed with persistent tepals or bracts that often grow into wings, spines, and other features in the fruit to aid in dispersal.
Morphology of Amaranthaceae in North America
Some Amaranthaceae Species Found In North America
Amaranthoideae Subfamily
Achyranthes aspera—Chaff Flower
This is a tall herb, up to 2 m tall, with silky or short-hairy stems and variable leaves, often somewhat egg-shaped to rounded. Sessile flowers are in a long spike surrounded by persistent awned bracts and bracteoles. These pantropical herbs are introduced to the southern USA and Mexico.
Amaranthus arenicola—Sand Amaranth
This dioecious annual (male and female flowers on separate plants) is common in sandy habitats, hence its common name. It has simple leaves and grows 2 m tall. Flowers occur in congested clusters (as shown in the photo). Native to the central and south Great Plains of the United States.
Amaranthus palmeri—Palmer’s Amaranth
This species is a fast-growing, aggressive herb that grows to 1.5+ m tall with diamond-shaped leaves on long stalks. Flowers are in terminal spikes or drooping branched inflorescences, as shown in the photo. Native to southern North America but now widely introduced and considered one of the most noxious weeds in the world. It is also edible and highly nutritious and can be used as a food crop in marginal environments.
Amaranthus retroflexus—Red Root Amaranth
It is a tall herb, growing to 3 m tall; is pubescent and hairy; and has rhombic or ovate leaves with long petioles. Flowers are in terminal and axillary spikes or panicles. It is believed to be native to eastern and central North America.
Camphorosmoideae Subfamily
Bassia scoparia—Summer Cypress
This annual herb grows up to 1.5 m tall and has linear–lanceolate leaves that often curl and a stem that is often reddish. Inconspicuous flowers grow in the leaf axils with much more conspicuous 0.5-1 cm long bracts. This Amaranthaceae member is a highly invasive Eurasian introduced species.
Chenopodioideae Subfamily
Atriplex canescens—Four-Wing Saltbush
This lovely woody shrub has the occasional spine on its branches, as well as plenty of more or less stalkless, somewhat oblong leaves and tiny flowers in congested spikes, as shown here. It produces conspicuous, winged greenish bracteoles that expand in fruit and turn papery and beige, becoming wings. This common Amaranthaceae member is native and widespread in the western USA.
Atriplex confertifolia—Spiny Saltbrush
This one is similar to A. canescens but with shorter, wider leaves, unwinged fruits, and many more spines on its branches. It’s also native to dry areas of the western USA, especially in the Great Basin region.
Chenopodiastrum simplex—Giant-Seeded Goosefoot
This herb has larger leaves than most of the family; they are 3–10 cm long and more than half as wide, with irregular, large pointy teeth, lobes, or lobules (of varying depths), mostly hairless stems and leaves, and small flowers without petals. It is native to much of North America.
Chenopodium album—White Goosefoot
This plant is a very common erect annual with visible lines down its stems in green or reddish-purple. Their leaves are diamond-shaped to eggshaped, and their flowers are in compact cymes in terminal or lateral spikes. It was introduced from Eurasia and is widespread in North America.
Krascheninnikovia lanata—Winterfat
This is a small shrub with flat lance-shaped leaves. Leaves and stems are both white and woolly, turning reddish. Its fruits (utricles) are densely woolly and visible all winter, giving it its common name of “winterfat.” The silky hairs help them disperse in the wind. It is endemic to western North America from Canada south to northern Mexico.
Gomphrenoideae Subfamily
Froelichia floridana—Large Cottonweed or Plains Snakecotton
A small annual with a single erect or ascending stem and leaves on the bottom third of the plant that are lanceolate to linear with silky-wooly hairs. Flowers are in hairy spikes, and the fruits are flask-shaped utricles. Native to the central and eastern USA and northern Mexico.
Gomphrena serrata—Prostrate Globe Amaranth
An erect or prostrate perennial or annual, with a pilose stem and obovate to oblong pilose leaves that are sessile to petiolate. Flowers in a head covered by white lanceolate bracteoles. Native to the southeastern USA, south to the tropical Americas.
Iresine diffusa—Juba’s Bush
This is a branched erect to clambering annual to perennial with elongated egg-shaped leaves that are 3 – 14 cm long and hairless to woolly-hairy. Flowers are in woolly-hairy branched open inflorescences (males) or compacted ones (females). This species is native to South America and has been introduced into North America.
Salsoideae Subfamily
Halogeton glomeratus—Salt Lover
This well-branched annual has narrow fleshy blue-green leaves tipped with long spines and flowers that grow densely along the branches with large, conspicuous, waxy, winged bracts. This species is native to Central Asia and introduced in western North America. It is often easy to spot because it is a halophyte, or salt-loving species that grows where many other plants cannot.
Salsola tragus aka Kali Tragus—Tumbleweed
This is a low-growing annual with branched and tangled stems and firm, more or less linear & usually very spine-tipped leaves. Flowers are surrounded by long spiny bracts and a disk of winged white/pink sepals. This Amaranthaceae member is from Russia and widely introduced in western North America. It is often our most common tumbleweed, breaking easily at the base when mature to roll across the plains and dispersing its seeds.
Uses of Amaranthaceae
The Amaranthaceae family has a few cultivated ornamentals that are from Amaranthus, Gomphrena, Ptilotus, and Iresine. Some of our most noxious weeds are from Amaranthus spp., Kali tragus, and Bassia scoparia.
Amaranthus species are also used as food in many parts of the world. In the Americas, Native American, Mesoamerican, and Andean civilizations all used to cultivate it for both the greens, eaten as a vegetable, and the seeds, which were often ground into flour. Amaranth seeds and flour are gaining renewed interest as they make a suitable replacement for wheat for those with grain allergies and gluten intolerance, and they are incredibly tough and able to grow where most conventional crops like wheat and corn cannot.
Other commercially grown species include quinoa (Chenopodium quinoa), spinach (Spinacia oleracea), and the sugar beet and Swiss chard from Beta vulgaris.
Ecosystem and Wildlife Values of Amaranthaceae
The Amaranthaceae often form keystone browse, forage, and habitat in extreme arid, semi-arid, and saline regions where most flowering plants cannot survive and often provide primary nutrition for herbivore communities in those regions. For instance, (Atriplex), winterfat (Krascheninnikovia), hopsage (Grayia), and bluebush (Maireana) retain green, protein- and mineral-rich foliage throughout dry seasons and winter months, providing critical forage for pronghorn antelope, mule deer, bighorn sheep, and more. And succulent halophytes (Salicornioideae and Suaedoideae) often drive estuarine and intertidal trophic webs.
The dense seed production of the Amaranthaceae also makes them invaluable food sources for songbirds, gamebirds, and granivorous small mammals. They also act as larval hosts for numerous butterfly and moth species and provide late-season nectar for pollinators.
Scientific Botanical Description of the Amaranthaceae
Habit & Leaf Form of Amaranthaceae
The Amaranthaceae are mostly annual or perennial (rarely biennial) herbs or subshrubs, some shrubs, and a few lianas and small trees. Stems are often ribbed or distinctly swollen at the nodes. In halophytic and xerophytic lineages (notably Salicornioideae and Salsoloideae), stems frequently become fleshy, articulated/jointed, and photosynthetic, with the leaves reduced. The wood of the perennial stem has a typical anomalous secondary growth, and only the subfamily Polycnemoideae has normal secondary growth.
Leaves may be well-developed, much reduced, or absent, and they may be minute to large. Usually, there is no basal aggregation of leaves, except sometimes in Ptilotus and basal Chenopodioideae. Leaves are arranged alternate or opposite, and they are usually herbaceous but can also be fleshy or membranous. The leaves are simple, petiolate or sessile, connate or not, sheathing or not, and flat or terete; they are also exstipulate and epulvinate. The lamina is either one-veined or pinnately veined. Various hair shapes and features are often present and become diagnostic at the genus and tribal level.
Flowers of Amaranthaceae
The Amaranthaceae are usually hermaphroditic but otherwise may be monoecious, andromonoecious, gynomonoecious, dioecious, androdioecious, or rarely polygamomonoecious. Flowers are solitary, paired (axillary), or aggregated in terminal or axillary cymes, spikes, heads (often with conspicuous persistent bracts and bracteoles), panicles, or thyrses. The hypogynous disk is absent except in Chenopodioideae, where it is usually present; otherwise, nectary tissue is typically found along the margins of the staminal cup or filament tube.
Flowers are small to minute in size and subtended by a primary bract and typically two lateral bracteoles, which may be scarious, persistent, carinate, spinose, or modified into accrescent valves that enclose the pistillate flower.
The perianth is made of tepals that are typically dry, scarious, and papery/chaffy in Amathrathoideae and Gomphrenoideae but are otherwise sepaloid or fleshy or may be vestigial or absent.
When present, there are 3–5 (1–6) tepals that are free or connate basally but may be deeply fused in Salicornioideae. They are typically persistent and often accrescent in fruit, often enclosing the fruit with wings, tubercles, or spines.
Androecium of Amaranthaceae
The androecium consists of 2-5 (1–10) members that are either free of the perianth or slightly adnate to the base of the tepals and always arranged in one whorl. All members are usually unequal except in the Chenopodioideae and some Ptilotus, where they are all equal.
The filaments are characteristically 1 adelphous, with filaments usually connate into a shallow nectariferous cup or fused for most of their length into a staminal tube but are free in some subfamilies.
Pseudostaminodes (sterile teeth, fringed lobes, or petaloid appendages) are often seen in Amaranthoideae and Gomphrenoideae, while in reduced or unisexual flowers, true staminodia may also occur.
Anthers are dorsifixed or basifixed, introrse, and dehisce by longitudinal lateral slits. They are dithecal, 2-locular (tetrasporangiate) in Amaranthoideae, Chenopodioideae, Salsoloideae, Suaedoideae, Salicornioideae, and Betoideae and are monothecal, 1-locular (bisporangiate) in Gomphrenoideae and Polycnemoideae.
Gynoecium of Amaranthaceae
The gynoecium is syncarpous with 2–3 (rarely 4–5) fused carpels forming a strictly unilocular ovary. The ovary is superior and mostly sessile and rarely short-stipitate, but it can sometimes be semi-inferior when sunken into the swollen floral receptacle.
The gynoecium is stylate or non-stylate. When present, there is one primary style with 2-3 (-5) apical branches or 2-5 distinct filiform or subulate styles that are free or partially connate. There are 1-3 stigmas that are of the dry type and papillate.
Placentation is always basal. The vast majority possess a single ovule per locule on an erect or curved funiculus. Ovules are campylotropous to amphitropous, bitegmic, and crassinucellar, non-arillate (though occasionally with a small caruncle/funicular arillode).
Fruit of Amaranthaceae
The Amaranthaceae fruits are mostly dry, 1-seeded, indehiscent utricles or achenes/nutlets, or circumscissile capsules (pyxidium/pyxis). However, there is considerable variability, and they may be fleshy berries or, more often, false berries that form when the accrescent perianth becomes fleshy or when multiple floral bases fuse into a multi-seeded aggregate.
Persistent or accrescent perianths and bracteoles are very common, often forming wings, spongy valves, spines, or horns that assist in seed dispersal.
Seeds are non-endospermic and contain starch. Perisperm is present (abundant, mealy) or sometimes absent in Chenopodioideae.
Taxonomy of Amaranthaceae
The Amaranthaceae family (sensu lato, including the Chenopodiaceae) comprises about 180 accepted genera and about 2000–2500 species within the core eudicot order, Caryophyllales. Under modern phylogenetic circumscription established by the Caryophyllales Network (Kadereit et al., 2011; Hernández-Ledesma et al., 2015; APG IV), the family is delineated into 10 distinct subfamilies.
Amaranthoideae Subfamily
The Amaranthoideae are annual or perennial herbs, subshrubs, shrubs, lianas, or occasionally small trees. Cuticle waxes lack platelets, and hairs are predominantly uniseriate (simple, dendroid, or stellate). The inflorescences are solitary or branched, typically forming dense spikes, racemes, thyrses, or heads. The bracts are persistent or disarticulating, and bracteoles (2) may be scarious, chataceous, or spinescent. The perianth is typically scarious or with membranous tepals; there are 1-5 stamens; it typically possesses staminodes or pseudostaminodes; and the anthers are bilocular, a key diagnostic trait.
The Betoideae are annual to perennial herbs or occasionally dwarf subshrubs or woody climbers. Bracteoles are usually present; the perianth has 5 (or 3-) parts that are herbaceous or coriaceous and often persistent, hardened, or accrescent in fruit. The androecium has 5 (rarely 1-) members, and the gynoecium is sometimes partly inferior. The fruit is a pyxidium (circumscissile capsule) with the top coming off like a lid or an indehiscent capsule in a hardened or accrescent perianth.
The Camphorosmoideae are often shrubs or subshrubs or may be annual herbs and exhibit either C₃ or C₄ photosynthesis. Their leaves are simple and linear to semi-terete, often fleshy or succulent, bearing hairs with swollen bases, and are without stipules. The styles are filiform with papillae all around. The perianth is herbaceous and becomes accrescent and heavily modified, producing wings, spines, tubercules, or horns or rarely becoming fleshy. There are 2-3 filiform stigmas entirely covered in papillae. The fruit is an indehiscent utricle.
The Chenopodioideae are annual herbs or short-lived perennial herbs, subshrubs, or shrubs that are more or less succulent and often have swollen nodes and farinose (or sometimes glandular) hairs, preferring dry or saline temperate to subtropical habitats. Flowers are small and have a greenish perianth that often becomes more elaborate after flowering and is accrescent with the usually indehiscent fruits, but occasionally the perianth is missing and enclosed by 2 accrescent bracteoles instead. An annular to horseshoe-shaped embryo surrounding a copious, mealy perisperm is also characteristic.
The Corispermoideae are annual herbs without any C₄ photosynthesis (strictly C₃). The inflorescence is spicate, simple, compact, or sometimes globular, and lacking bracteoles. Leaves are mostly alternate, sessile, or petiole-like. Hairs are branched or stellate. The perianth has 0-5 drastically reduced membranous tepals that are not accrescent. The fruit is a characteristic compressed utricle/achene, typically bordered by a scarious or membranous marginal wing and capped with two persistent beak-like style/stigmas.
The Gomphrenoideae are annual to perennial herbs or subshrubs that often possess laterally compressed, scarious, and often crested/keeled bracteoles that clasp the flower, with a perianth that is free to connate. Anthers are bisporangiate and monothecal, and their filaments are more or less connate into a tube, typically bearing lateral appendages or pseudostaminodes. Their stigma is either capitate or bilobed.
The Polycnemoideae are annual to perennial herbs or small shrubs that often inhabit saline habitats, and unlike other subfamilies, they exhibit normal secondary growth derived from a single persistent vascular cambium. Leaves are needle-like or succulent, bracts are disarticulating, and bracteoles are often equal or larger than the perianth. Flowers are axillary, the perianth is petaloid but never modified, and the androecium is basally connate with bisporangiate anthers similar to Gomphrenoideae.
The Salicornioideae are succulent, hygrohalophytic annual or perennial herbs, subshrubs, or low shrubs, usually with glabrous and articulated stems. Leaves are opposite to alternate but typically reduced to scales, short lobes, or a rim. The inflorescence is dense, succulent, spike-like, and terminal or lateral. The perianth has 3-4 (2-5) parts, is typically at least partially connate, and is often embedded in the axils of fleshy bracts, where it often becomes spongy, crustaceous, or horny in fruit.
The Salsoideae are annual or perennial herbs, subshrubs, shrubs, or occasionally small trees with predominantly C₄ photosynthesis. Stems and leaves are often succulent, with branches often articulated and leaves that range from fleshy and terete to reduced to scales, often mucronate or spinescent. Inflorescences are solitary or in small cymules in leafy spikes or panicles, with flowers subtended by a small bract and 2 prominent, fleshy or scarious bracteoles. Anthers have colored appendages, and their stigmas are flattened. Scarious wings usually develop from the perianth in fruit.
The Suaedoideae are annual to perennial herbs or shrubs with stems that are usually glabrous and rarely jointed. They typically have well-developed, succulent, terete leaves and exhibit three photosynthetic pathways, including C₃ and classical C₄, with novel single-cell C₄ also seen in a few species. The inflorescence is solitary or 2-10-flowered glomerules or cymes with small fleshy flowers and a persistent perianth that becomes accrescent, spongy, succulent, berry-like, or develops wings or lobes. The styles are filiform, and the stigma may be capitate but is papillate all around.
Bienertia (4), Suaeda (94).
Key Differences From Similar Families
The Amaranthaceae are most likely to be confused with the Polygonaceae, which are also weedy herbs that produce small apetalous flowers in dense spikes, but the Polygonaceae all have a characteristic sheathing stipule (ochrea) at their nodes, while the Amaranthaceae always lack stipules of any kind. The Polygonaceae also produce 3-angled or lenticular achenes for fruits.
Occasionally woody Amaranthaceae may be confused with Achatocarpaceae, but the latter always has normal secondary growth instead of only occasionally in the Amaranthaceae (only in the Polycnemoideae). The Amaranthaceae also usually have dry fruits rather than the succulent berries found in the Achatocarpaceae.
Global Distribution of Amaranthaceae
The Amaranthaceae family is a temperate to tropical, truly cosmopolitan family missing only from Antarctica and the most extreme Arctic areas. It is widespread, both native and introduced, throughout North America, Central America, the Caribbean, and South America.
Distribution of Amaranthaceae in the Americas
Canadian Amaranthaceae Genera
Amaranthoideae:Achyranthes 1 sp. intro in ON; Amaranthus 20 spp. intro in BC, NT, NB, NS, PE, and NL Island, with some native in AB, SK, MB, ON, and QC.
Camphorosmoideae: Bassia 2 spp. intro to all S provinces except NL, NS, and PE.
Chenopodioideae:Atriplex 18 spp. native to all of Canada and Greenland; Axyris 1 sp. intro to all of S Canada exc PE and NL; Blitum 4 spp., including 2 native and 2 intro in all of Canada inc Arctic but ephemeral PE and NL (exc Labrador); Chenopodiastrum 4 spp. inc 1 native to all S provinces exc NL and 3 spp. intro into S Canada, YT, and NT; Chenopodium 19 spp. native to YT, NT, BC, AB, SK, MB, ON, QC, and NS, and intro in NB, PE, NL, NU (and Greenland); Dysphania 4 spp., including 3 intro to BC, ON, QC, NB, and NS and 1 native to ON, QC, and MB; Krascheninnikovia 1 sp. native to YT, AB, SK, and MB; Lipandra monospecific intro to BC, SK, MB, ON, QC, and NB; Oxybasis 6 subcosmopolitan spp. including 3 native to all of Canada including the Arctic but excluding PE and NL, and 3 spp. intro to E Canada; Spinacia 1 sp. intro and ephemeral in YT, NT, AB, and MB; Stutzia 1 NW NAM endemic sp. native to AB and SK; Suckleya monospecific N-C NAM endemic sp. native to AB and SK.
Corispermoideae:Corispermum 6 spp., mostly native to BC, AB, SK, MB, ON, QC, YT, and NT.
Gomphrenoideae: Froelichia 1 sp. intro to ON.
Polycnemoideae: Polycnemum 3 spp. intro to BC and ON.
Salicornioideae: Salicornia 5 spp. native to all of Canada except Labrador, it’s found in coastal and inland saline areas. Salsoideae: Salsola (inc. Kali) 3 spp. intro to all S provinces.
Suaedoideae: Suaeda 4 spp. native to all of Canada except for Labrador.
USA AmaranthaceaeGenera
Amaranthoideae: Achyranthes 4 spp. including 2 intro to TX, LA, FL, AL, KY, WV, IN, OH, and MD, plus 2 spp. endemic to HI; Aerva 1 sp. native and believed extinct in HI; Amaranthus 45 spp. both intro and native in all of the USA, including HI and intro in AK; Celosia 4 spp., including 1 native to TX and FL and 3 intro to most of E USA from WI S to MS and all E exc MI, GA, SC, RI, MA, NH, ME, and inc MO, LA, KS, UT; Charpentiera 5 spp. endemic to HI; Digera monospecific sp. intro to NJ; Hermbstaedtia 1 sp. intro to MD.
Betoideae: Aphanisma monospecific SW NAM endemic sp. native to CA; Beta 2 spp. intro to MT, OR, CA, UT, TX, MO, AL, SC, NC, VA, WV, PA, MI, NY, CT, MA, RI, NH, and ME.
Camphorosmoideae:Bassia 6 spp. including 2 native and 4 intro to most of the USA except AR, GA, and FL, and intro to HI; Enchylaena 1 sp. intro to CA; Neokochia 2 W USA endemic spp. of OR, CA, ID, NV, MT, WY, CO, UT, AZ, NM, and TX; Spirobassia monospecific intro to PA, NJ, MD, NY, and CT.
Chenopodioideae: Atriplex 94 spp. mostly native with some intro, found in most of the USA, including AK, but excluding AR and TN, and intro HI; Axyris 1 sp. intro to MT, CO, ND, WI, and MO;Blitum 4 spp. inc. 3 native and 1 intro to most of USA except AR S to LA and E to NC S to FL plus VA, MD, and DE; Chenopodiastrum 2 spp. including 1 native to most of the USA and AK but excluding OR, AZ, AL, GA, SC, and FL where intro and 1 sp. intro scattered throughout USA; Chenopodium ~40 spp. native and intro to all of the USA inc AK and HI; Dysphania 11 spp. native and intro to the entire USA, intro in AK and HI; Extriplex 2 SW NAM endemic spp. native to CA, inc 1 narrow endemic; Grayia 4 W USA endemic spp. from MT S to NM and all W; Krascheninnikovia 1 spp. native to W USA from ND S to TX and all states W; Lipandra monospecific sp. intro to OR, WI, IL, MI, PA, NJ, NY, CT, and ME; Neomonolepis monospecific former SW NAM endemic of CA, NV, and OR; Oxybasis 6 spp., including 2-3 native to most of USA except the SE states and 2-3 spp. intro to much of the same range but including FL, AL, IL, IN, KY, WV, VA, NC, and VT; Proatriplex monospecific S-C USA endemic of UT, AZ, CO, and NM; Spinacia 1 sp. intro to WA, OR, CA, UT, TX, KS, SC, NC, VA, OH, PA, CT, MA, NY, NH, and ME; Stutzia2 NW NAM endemic spp. native to CA, NV, MT, WY, CO, ND, SD, and NE; Suckleya monospecific N-C NAM endemic sp. native to MT, ND, WY, CO, NM, AZ, NE, OK, and TX; Teloxys monospecific sp. intro to MI, NY, and AK.
Corispermoideae: Corispermum 9 spp. native and intro in most of the USA except ME, VT, NH, PA, MD, DE, WV, VA, TN, NC, SC, LA, MS, AL, and FL, and it is native in AK and extinct in CA.
Gomphrenoideae: Alternanthera 11 spp. including 1 native to FL and the rest intro to CA, AZ, NM, TX, OK, MO, AR, LA, IL, KY, TN, MS, AL, GA, SC, NC, VA, MD, PA, NJ, NY, and HI; Froelichia 6 former Americas endemic spp. native to most of the USA except WA, OR, ID, MT, NV, UT, ND, VT, RI, and ME, including 2 narrow endemics of TX, and intro CA?; Gomphrena 8 spp. native to AZ, NM, TX, LA, FL, GA, and VA, and intro to PA, MD, OH, NY, MA, and HI; Guilleminea 1 sp. native to CA, AZ, NM, TX, OK, CO, SC, MD, AR, and LA; Iresine 6 former Americas endemic spp. native to AZ, NM, TX, KS, OK, MO, AR, LA, IL, IN, KY, TN, MS, AL, GA, FL, SC, NC, MD, and PA and intro to HI; Tidestromia 5 S NAM & Caribbean endemic spp. native to CA, NV, UT, AZ, CO, NM, TX, LA, OK, KS, SD, MO, IL, and PA.
Polycnemoideae: Nitrophila 2-3? SW NAM endemic spp. native WA, OR, CA, NV, UT, and AZ, including 1 narrow endemic of the Mohave Desert; Polycnemum 1 sp. intro to IN, NY, MD, DE, and NH.
Salicornioideae: Allenrolfea 1 SW NAM endemic sp. native to OR, ID, CA, NV, UT, AZ, NM, and TX (other 2 are endemic to Argentina); Arthroceras monospecific SW NAM endemic sp. native to CA; Salicornia 5 spp. native most of the USA including AK but exc. AZ, OK, AR, TN, KY, IN, WI, WV, PA, and VT, and it’s intro in HI and MI, and extirpated IL, found in coastal & inland saline areas.
Salsoideae: Caroxylon 1 sp. intro in CA; Halogeton 1 sp. intro in all of W USA from MT S to NM and all W, plus SD and NE; Salsola 6 spp. intro to all of the USA including HI.
Suaedoideae: Suaeda 13 spp. intro and native to most of the USA except IA, AR, TN, WV, and VT, and it is native in AK.
Mexico AmaranthaceaeGenera
Amaranthoideae: Achyranthes 2 spp. inc 1 intro in all of Mexico and 1 native to S Mexico; Amaranthus ~35? spp. native through all of Mexico and intro to Mexican Pacific Is.; Celosia 3? spp. native to most of Mexico except where intro in Mex, Cd Mex, and Tlx; Chamissoa 1 Mexico & neoendemic sp. native in all of Mexico; Cyathula 2 spp. native to Nay, Jal, Col, Gro, Mch, Oax, Chp, Pue, Ver, Tab, Cam, QR, and Yuc; Lagrezia 1 sp. Mexico endemic of Nay, Jal, Col, Mch, Gro, Oax, Chp, Tab, Cam, Yuc, and QR (most of genus is Madagascar); Pleuropetalum 2 Mexico & neoendemic spp. native to N+SE+SE Mexico, Ver.
Betoideae: Aphanisma monospecific SW NAM endemic sp. native to BC, BCS?, and Mexican Pacific Is.; Beta 2 spp. intro to BC, BCS, Son, and Sin.
Camphorosmoideae: Bassia 2 spp. intro to BC, BCS, Son?, and Sin?.
Chenopodioideae: Atriplex ~30 spp. native through all of Mexico, including Mexican Pacific Is.; Blitum 4 spp., inc. 2 native and 2 intro to BCN, BCS, Son, Sin, Chi, NL, Tam, Dgo, Zac, SLP, Gto, Qro?, and Hgo?; Chenopodiastrum 1 sp. intro to BC, BCS, Son, Sin, Nay, Jal, Col, Mch, Gro, and Oax; Chenopodium ?? spp. native throughout all of Mexico; Dysphania 8 spp., inc. 7 native and 1 intro, found in all of Mexico and intro Mexican Pacific Is.; Extriplex 1 SW NAM endemic sp. native BCN and BCS?; Krascheninnikovia 1 sp. native to N Mexico in BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Qro, Ags, Gto, and SLP; Neomonolepis monospecific former SW NAM endemic native to BCN and BCS?; Oxybasis 4 3 subcosmopolitan spp., including 2 native (1 endemic) to Chi, Coa, NL, Tam, Dgo, Zac, Ags, SLP, Gto, Qro, Hgo, Mex, Cd Mex, Mor, Nay, Jal, Col, Gro, Mch, and Oax, and 2 spp. intro to BC, BCS, Son, and Sin.
Corispermoideae:Corispermum 1 sp. native to Chi, Dgo, Zac, SLP, Hgo, Gto, Qro, NL, Tam, and Coa.
Gomphrenoideae: Alternanthera ~6 spp. native throughout all of Mexico; Froelichia 6 former Americas endemic spp. native in all of Mexico, including 1 narrow endemic of BCS; Gomphrena ~16 spp. native to all of Mexico; Guilleminea 2 spp. native to N+SW+C Mexico; Hebanthe 1 sp. mostly neoendemic genus native to most of Mexico exc. the NW+C; Iresine ~20 spp. native to all of Mexico, including many endemics; Pfaffia 1 sp. mostly neoendemic genus native to S Mexico in Nay, Jal, Col, Mch, Gro, Oax, Chp, Cam, Tab, QR, and Yuc; Tidestromia 6 NAM & Caribbean endemic spp. native to BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Gto, Qro, SLP, Hgo, and Ags, inc. 1 narrow endemic of Coa.
Polycnemoideae: Nitrophila 1 sp. native to NW Mexico.
Salicornioideae: Allenrolfea 1 SW NAM endemic native to BCN, BCS, Son, Sin, Chi, NL, Tam, Dgo, and SLP (other 2 spp. endemic to Argentina); Arthroceras monospecific SW NAM endemic sp. native to BC, BCS, Son?, and Sin?; Salicornia 4?spp. native to most of Mexico except Pue, found in coastal & inland saline areas.
Salsoideae: Salsola ~6 spp. intro to BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Gto, Qro, and Ags.
Suaedoideae: Suaeda ~17 spp. native in all of Mexico including the Mexican Pacific Is.
Neotropical AmaranthaceaeGenera
Amaranthoideae: Achyranthes 2? spp. including 1 intro to CAM (exc. Costa Rica), Bahamas, Turks-Caicos, Aruba, Antilles (exc. Cayman Is.), SW Caribbean, Galapagos, and tropical SAM S to Peru, Bolivia, C+SE Brazil (exc. Ecuador) plus 1 native to Cuba, parts of the Antilles, Guatemeal, Colombia, and Venezuela; Amaranthus ~45 spp. native throughout N Caribbean, Antilles, SW Caribbean, Trinidad-Tobago, CAM, all of SAM, and Galapagos, and is intro to Bermuda and Juan Fernandez Is.; Celosia several spp. are native to Guatemala, El Salvador, Honduras, Nicaragua, Panama, Cuba, Hispaniola, Puerto Rico, Bahamas, Leeward & Windward Is., Venezuela, Colombia, Ecuador, Peru, and Brazil, and are intro in Belize, Cayman Is., Galapagos, Trinidad-Tobago, C Brazil, Bolivia, NE Argentina, and Paraguay; Chamissoa 3 Mexico & neoendemic spp. of Greater Antilles (exc. Cayman Is.), CAM S through tropical SAM to N Argentina exc. French Guiana and N Chile; Cyathula 3 spp. inc 2 native to CAM, Cuba, Hispaniola, Jamaica, Trinidad-Tobago, Colombia, Venezuela, Brazil, Ecuador, Peru, and Bolivia, and 1 intro to Puerto Rico, Leeward & Windward Is, Venezuelan Antilles, French Guiana, Suriname, Guyana; Hebanthodes monospecific endemic of Peru; Herbstia monospecific E SAM endemic of E+S Brazil, Paraguay, and NE Argentina; Lecosia 2 narrow endemic spp. of E Brazil (not in APG); Pleuropetalum 3 Mexico & neoendemic spp. native to CAM, Venezuela, Colombia, Ecuador, Peru, Bolivia, and Galapagos (1 narrow endemic of Galapagos).
Betoideae: Beta 2 spp. intro to Honduras, Cuba, Cayman Islands, Dominican Republic, Puerto Rico, Ecuador, N & C Chile, Juan Fernández Is., Argentina, and Uruguay.
Camphorosmoideae: Bassia 1-2 spp. intro to C. Chile and N. Argentina; Maireana 1 sp. intro in N Chile, Desventurados Is.
Chenopodioideae: Atriplex ~20? spp. native to Honduras, Bermuda, Antilles (exc. Windward Is.), SW Caribbean, Venezuela, Colombia, Peru, Bolivia, Paraguay, Chile, Argentina, Uruguay, and S Brazil; Blitum 1 sp. intro to N Argentina; Chenopodiastrum 1 sp. intro to Honduras, Nicaragua, Panama, Bermuda, Bahamas, Turks-Caicos, Antilles (exc. Cayman Is, Windward Is.), Venezuela, Colombia, Ecuador, Peru, Bolivia, C+E Brazil, Chile, N Argentina, and Uruguay; Chenopodium ??spp. native to Honduras, Panama, Colombia, Ecuador, Peru, Chile, Argentina, Paraguay, and S Brazil, and intro C+E Brazil, Bermuda, Bahamas, Cuba, Dominican Republic, and Trinidad-Tobago; Dysphania 15 spp. native to CAM, Bermuda, all of SAM except Ecuador, French Guiana, Suriname, and Guyana where it is now intro, also intro in the Bahamas, Antilles, SW Caribbean, Trinidad-Tobago, Galapagos, and Juan Fernandez Is.; Holmbergia monospecific C SAM endemic of Bolivia, Paraguay, Uruguay, and N Argentina; Oxybasis 5 subcosmopolitan spp., including 3 native (2 endemic) of Peru, Bolivia, Chile, and NW+S Argentina and 2 spp. intro to Argentina; Spinacia 1 sp. intro to Hispaniola and Cayman Is.
Gomphrenoideae: Alternanthera ~100? spp. native to Bermuda, Bahamas, Turks-Caicos, Aruba, Antilles, CAM, and all of SAM, including Galapagos, excluding S Chile; Froelichia 8 former Americas endemic spp. native to Guatemala, Honduras, Nicaragua, Cuba, Hispaniola, Jamaica, Colombia, Venezuela, Brazil, Ecuador, Galapagos, Peru, Bolivia, Paraguay, Uruguay, and N Argentina, including 4 narrow endemics of Galapagos (2), Para N Brazil, and Paraguay; Froelichiella monospecific endemic of C Brazil; Gomphrena ~90 spp. native to all of CAM and SAM, exc. S Chile, plus much of the Antilles region; Guilleminea 4 spp. native to Cuba, Hispaniola, Colombia, Ecuador, Peru, Bolivia, C Brazil, Paraguay, N Argentina, and Uruguay, inc. 2 endemics of Cuba and Uruguay; Hebanthe 6 spp. mostly neoendemic genus native to CAM and SAM S to N Argentina, exc. N Chile, Uruguay; Iresine ~20 spp. Mexico + former neoendemic natives throughout all of CAM, the Bahamas, Antilles (exc. Aruba and Netherlands Antilles), and tropical SAM to N Argentina (exc. French Guiana and N Chile); Pedersenia 8 neoendemic spp. of Honduras S to Colombia, Venezuela, Ecuador, Peru, Paraguay, and N Brazil, plus Puerto Rico and the Windward Is.; Pfaffia ~26 neoendemic spp. native to S Mexico, Haiti, Leeward & Windward Is., Venezuelan Antilles, Trinidad-Tobago, Costa Rica, and tropical SAM S to N Argentina (except N Chile); Pseudoplantago 2 SAM endemic spp. endemic to Venezuela (1) and S Brazil + NE Argentina (1); Quaternella 3 Brazil endemics exc. N Brazil; Tidestromia 1 S NAM & Caribbean endemic spp. native to the Dominican Republic; Xerosiphon 2 spp. endemic to most of Brazil except the south.
Polycnemoideae: Nitrophila 2 SAM endemic spp. native to Argentina and N. Chile.
Salicornioideae: Allenrolfea 2 Argentina endemic spp. native to all of Argentina; Heterostachys 2 neoendemic spp. native to Hispaniola, Colombia, Venezuela, Paraguay, and Argentina, including 1 narrow endemic of Buenos Aires, Mendoza & Rio Negro, Argentina, at the N limit of Patagonia; Mangleticornia monospecific endemic of Ecuador and Peru; Salicornia 5-6 spp. native in coastal and inland saline areas of the Bahamas, Turks and Caicos, Antilles (exc. Windward Is.), Colombia, Venezuela, Ecuador, Peru, Bolivia, Paraguay, S Brazil, Argentina, Chile, and Uruguay.
Salsoideae: Salsola 2-3? spp. intro to Uruguay, C+S Chile, and Argentina.
Suaedoideae: ~7-10 spp. native to the Bahamas, Turks and Caicos, Cuba, Hispaniola, Leeward Is., Peru, Bolivia, Chile, and Argentina, and extinct or extirpated Juan Fernandez Is.
Patagonia AmaranthaceaeGenera
Amaranthoideae:Amaranthus 4 spp. native to C+S Argentina, C+S Chile.
Betoideae: Beta 1 sp. intro to C Chile and S Argentina.
Camphorosmoideae: Bassia 1 sp. intro to C Chile and S Argentina.
Chenopodioideae:Atriplex 1 sp. native throughout Patagonia and intro to Falkland Islands; Blitum 2 spp. inc. 1 intro and 1 endemic to Patagonia; Chenopodiastrum 1 sp. intro C+S Chile and S Argentina; Chenopodium 1 sp. native throughout Patagonia; Dysphania 1 sp. native to all of Patagonia; Oxybasis 4 subcosmopolitan spp., inc. 3 native to C+S Chile, S Argentina, and Falkland Islands, and 1 sp. intro to Patagonia.
Gomphrenoideae: Alternanthera 1 sp. native just N of Patagonia in the mountains N of Bahia Blanca, S Argentina; Gomphrena 1-2 spp. native to S Argentina.
Polycnemoideae: Nitrophila 1 SAM endemic sp. of S Argentina near N limit of Patagonia.
Salicornioideae:Allenrolfea 1 Argentina endemic sp. native to S Argentina; Heterostachys 1 sp. is a narrow endemic of Buenos Aires, Mendoza & Rio Negro, Argentina, at the N limit of Patagonia; Salicornia 2? spp. native throughout all of Patagonia in salt marshes and lagoons.
Salsoideae: Salsola 1? sp. intro throughout Patagonia.
Suaedoideae: Suaeda 1 spp. native throughout Patagonia and the Falkland Islands.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, as well as personal observations in North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Flora of North America (FNA) (1993+). https://floranorthamerica.org/Main_Page.
Hernández-Ledesma, P., Berendsohn, W. G., Borsch, T., Mering, S. v., Akhani, H., Arias, S., Castañeda-Noa, I., Eggli, U., Eriksson, R., Flores-Olvera, H., Fuentes-Bazán, S., Kadereit, G., Klak, C., Korotkova, N., Nyffeler R., Ocampo G., Ochoterena, H., Oxelman, B., Rabeler, R. K., Sanchez, A., Schlumpberger, B. O. & Uotila, P. 2015. A taxonomic backbone for the global synthesis of species diversity in the angiosperm order Caryophyllales. Willdenowia 45(3): 281–383. DOI: 10.3372/wi.45.45301
Kadereit, G. & Freitag, H. 2011. Molecular phylogeny of Camphorosmeae (Camphorosmoideae, Chenopodiaceae): Implications for biogeography, evolution of C4-photosynthesis and taxonomy. Taxon 60(1): 51–78. DOI: 10.1002/tax.601006.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout the fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
25 Sep, 2022
18 Sep, 2022
How to Identify the Anacardiaceae or Cashew Family
Rhus typhina Staghorn Sumac plants with fruits (drupes). Page Last Updated August 28, 2026.
Introduction to the Anacardiaceae Family
When you learn to identify the Anacardiaceae family, you will quickly learn its most well-known members in North America, the sumac (Rhus spp.) and poison ivy (Toxicodendron spp.). I have always been fond of sumac trees, and I am not the only one. They are often used ornamentally for their ease of growing, brilliant fall colors, and striking pyramidal clusters of red drupes that persist all winter to feed the birds when few other food sources are available.
And of course, poison ivy is a crucial one to know, as anyone who has ever hiked in the forest and come across it will tell you, since it causes incredibly itchy contact dermatitis. There is an old saying, “Leaves of three, let it be,” since the Toxicodendron species that cause poison ivy rash have trifoliate leaflets. It is a good rule of thumb if you are unsure of your plant ID. But be aware that numerous innocuous species exist that also have trifoliate leaves, so do not assume it is always poison ivy.
Beginner’s Guide to the Cashew or Sumac (Anacardiaceae) Family
If you’re new to plant morphology, this is a perfect beginner’s description to learn to identify the Cashew (Anacaradiaceae) family, with no need to know any scientific jargon. For researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below.
Leaves and Stems of the Cashew Family
The cashew family consists of woody shrubs and trees or climbing vines with resin canals in their leaves, roots, and stems that often release a milky or resinous juice when damaged and that may be aromatic, turn black when it hits the air, and/or cause severe contact dermatitis. Leaves are often arranged alternately in a spiral pattern along the stem and may be simple (1 blade) or compound and made of multiple leaflets.
Flowers of the Cashew Family
The flowers are usually quite small and occur in branched clusters called panicles. Most flowers have 5 sepals and 5 petals, but some may lack petals or have petals that are more green and sepal-like. They often contain a ring-shaped nectary inside to attract pollinators.
Reproductive Features of the Cashew Family
These flowers are quite diverse in the family, with bisexual flowers that contain both male (stamens) and female (ovary, style, stigma) parts, or separate male and female flowers that may be on the same (monoecious) or separate plants (dioecious). There are usually 5-10 stamens and a superior ovary (sitting above the point of petal attachment) with 1 to 5 styles (the tube that collects pollen) on top.
Fruits of the Cashew Family
The fruit is usually a fleshy drupe (think cherry but usually smaller) containing a fleshy or resinous outer part and a single hard pit, but some species produce winged samaras. The fruits and sap of some species contain urushiol, the toxic oil responsible for the skin irritation of poison ivy (Toxicodendron species).
Morphology of Anacardiaceae in North America
Some Anacardiaceae Species Found in North America
Anacardioideae Subfamily
Mangifera indica—Mango
A 10-20 m tall tree with long, oblong leaves and large, edible drupes on very long stalks (peduncles). While originally native to Asia, this tree is widely cultivated in southern North America (mostly Mexico) and around the world in tropical and subtropical locations for its delicious fruits—the mango.
Pistacia vera—Pistachio
A small to medium-sized tree up to 10 m tall with deciduous, compound leaves made of opposite pairs of leaflets (pinnate) 10–20 cm long. Flowers have no petals, and male and female flowers occur on separate trees (dioecious). The fruit is a drupe containing the elongated pistachio “nut.” These flowers are male, and what you are seeing are masses of anthers.
Rhus aromatica—Fragrant Sumac
Fragrant sumac is a somewhat lemon-scented shrub with trifoliate lobed leaves and hairy red drupes. It is dioecious (separate male and female plants) with small and inconspicuous flowers on both. This shrub is native throughout the USA, Mexico, and southeastern Canada, often found growing in semi-arid and arid environments.
Rhus copallinum—Shining Sumac
Shining sumac is a tall shrub with glossy odd-pinnate leaves that have a conspicuously winged leaf “stalk” (rachis—visible in the photo), which is a diagnostic feature for identification. It is native to eastern North America but is often cultivated there and elsewhere.
Rhus glabra—Smooth Sumac
Smooth sumac is another tall shrub with hairless branches and odd-pinnate leaves, with 11 to 31 toothed leaflets. It produces large, densely branched clusters (panicles) of red drupes, like shown in the photo. It is native to eastern North America, with scattered populations also found in western North America.
Rhus microphylla—Littleleaf Sumac
Littleleaf sumac is well adapted to desert life with its tiny, odd-pinnate, glossy green, leathery, and hairy leaves that emerge after its tiny flowers have already bloomed. The fruits are small clusters of small hairy drupes. It is native to the southwestern USA and northern and central Mexico.
Rhus trilobata—Skunkbush Sumac
Skunkbush sumac is closely related to fragrant sumac, but it gets a bad rap because instead of smelling pleasant and lemony, it produces a pungent, bitter scent, but it’s not nearly as unpleasant as a skunk. This shrub has trifoliate lobed leaves (shown in the pic), flowers in catkins, and its fruits are hairy, sticky red drupes. It is native to western North America, including western Mexico.
Rhus typhina—Staghorn Sumac
Staghorn sumac is a large shrub with odd-pinnate leaves with 9 – 31 toothed leaflets and can be differentiated from the similar-looking R. glabra by its densely red-hairy stems and leaf stalks (petioles). It is native to the northeastern USA and southeastern Canada.
Toxicodendron radicans—Eastern Poison Ivy
Eastern poison ivy is a climbing vine (sometimes a shrub) with woody stems & trifoliate, shiny leaves that are usually not toothed. Flowers are small, greenish, and inconspicuous, and the fruit is a gray-white drupe. The whole plant may cause contact dermatitis. It is native to the eastern USA and Canada.
Toxicodendron rydbergii—Western Poison Ivy
Western poison ivy is a shrub with opposite trifoliate leaves that are often asymmetrical. The fruits are white, yellow, or brown drupes that are ribbed (green, as in the photo, when still immature). It is native throughout the USA and Canada but is mostly found in the West.
Uses of the Anacardiaceae
Some Anacardiaceae are edible plants, such as cashew nuts (Anacardium and the fleshy peduncle of the cashew apple), mango (Mangifera), Jamaica plum, hog-plum, imbu (a plum-like fruit from Spondias), and Amarula cream (from Sclerocarya typically made into a liqueur). Resins, oils, and lacquers are derived from Toxicodendron. Several non-native Anacardiaceae are cultivated in the Neotropics for their edible fruits, including Bouea macrophylla,, Harpephyllum caffrum, Mangifera indica, Schinus terebinthifolia, Sclerocarya birrea subspecies caffra, and Spondias dulcis. Many Anacardiacea species are notorious for their allergenic properties that often cause severe rashes, particularly Toxicodendronspp. (Poison Oak, Poison Ivies).
Ecosystem and Wildlife Values of the Anacardiaceae
The Anacardiaceae serve as keystone food resources and soil stabilizers across temperate and tropical biomes. They are crucial early-season nectar sources and late-season food plants (Rhus (sumac), etc.).
Several specialized lepidopterans and herbivorous insects are specially adapted to feed on the resinous foliage, including silk moths, specialized bees, and leaf miners.
Taxonomy of the Anacardiaceae Family
The Anacardiaceae have 873 species in 80 genera of the Sapindales order of core eudicots. There are two accepted subfamilies. Previously the family had several dissident genera that were “unplaced” but now have confirmed homes in those two subfamilies, mostly accepted as early-diverging or basal grades (Attilaea, Campnosperma, Buchanania, Koordersiodendron, and Pentaspadon).
Anacardioideae Subfamily
The Anacardioideae are trees or shrubs with black or colored resinous exudate, and crystals are present in the xylem. Leaflets’ margins are usually entire or sometimes toothed in temperate species, and the base of the petiole is often swollen. Flowers are 5(-7)-merous, the calyx is more or less connate basally, the gynoecium is typically 3-carpeled, and the stigma is dry and capitate or lobed. The fruit is a drupe that is layered with a crystalliferous endocarp and lacks the opercula seen in Spondiadoideae.
The Spondiadoideae (or Spondioideae, depending on the source) are deciduous or evergreen trees or shrubs with clear, non-allergenic resins or soluble gums that typically do not cause contact dermatitis. Flower pedicels are often articulated; the gynoecium has 4-5 (rarely 1-3 or up to 12) carpels, with distinct free or basally connate styles, and a stigma is only slightly expanded. The fruit is usually a drupe with a woody, often operculate endocarp, more than two-seeded (1-5), wrapped in an inner fibrous mesocarp.
The Anacardiaceae is typically confused with its sister family, the Burseraceae, which share similar vegetative habits. However, they can be distinguished by the anatropous or epitropous ovules with 2 per locule (though one is often abortive) compared to only one in the Anacardiaceae. They are also differentiated by the black resins and contact dermatitis of the Anacardiaceae rather than the aromatic and non-allergenic resins of the Burseraceae that rarely darken on contact with the air or cause contact dermatitis.
The Meliaceae also look superficially similar vegetatively, but they almost always have stamens with filaments fused into a staminal tube surrounding the ovary, while Anacaradiaceae stamens are free. Meliaceae also typically smell of garlic or cedar but lack resin ducts that oxidize black and cause contact dermatitis.
The Rutaceae can also sometimes be confused, but they feature aromatic oil glands (pellucid dots) on their leaves that the Anacardiaceae do not have, and they often possess axillary spines or modified stipular thorns that are generally lacking in the Anacardiaceae.
Scientific Botanical Description of the Anacardiaceae
Habit & Leaf Form of the Anacardiaceae
The Anacardiaceae are trees, shrubs, or self-supporting or climbing lianas, often with a milky juice that may be resinous or laticiferous and often turns black on exposure to the air; resins may be aromatic or odorless. Resin canals located in the inner fibrous bark and pith of the stems, roots, and leaves are characteristic of this family. Tannin sacs are very common.
Leaves are evergreen or deciduous, without stipules, and alternate (spirally arranged) or rarely opposite or subopposite (e.g., Bouea). They are simple or compound ternate, trifoliate, imparipinnate, or rarely paripinnate or bipinnate.
Lamina margins are entire to serrate, dentate, or deeply lobed. Primary venation is pinnate or rarely palmate, and secondary venation is eucamptodromous, brochidodromous, craspedodromous, cladodromous, or rarely reticulodromous. If present, cladodromous venation is diagnostic for certain genera in the Anacardiaceae family.
Domatia occur in several genera as pits, pockets, or hair tufts.
Flowers of the Anacardiaceae
Plants of the Anacardiaceae are sexually diverse and can be hermaphroditic, monoecious, dioecious, gynodioecious, or polygamomonoecious. Pollination is predominantly entomophilous, though anemophily is seen in reduced-perianth genera like Pistacia.
Flowers are small, actinomorphic (rarely slightly zygomoprhic), usually 3- to 5-merous, and arranged in terminal or axillary panicles (thyrses), racemes, or spikes. A hypogynous, fleshy, intrastaminal nectar disc (annular or lobed) is characteristically present.
The perianth has a distinct calyx and corolla, may be sepaline, or sometimes is reduced to minute bracts.
The calyx has 3–5 basally connate, imbricate lobes in one whorl that may be shorter or longer than the tube.
The corolla, when present, usually has 3–5 imbricate or valvate petals that are free, but can rarely be connate basally with lobes longer than the tube.
Androecium of the Anacardiaceae
The androecium has 1–10(11–12) parts arranged in 1 or 2 whorls. In diplostemonous flowers, the outer whorl is antesepalous, while the inner whorl is antepetalous, but when there are 5 stamens, they are oppositesepalous.
Androecial members are inserted at the base of the hypogynous disc, free of the perianth and of one another, or sometimes basally connate into a short ring.
There may be 0-9 staminodes, with highly reduced flowers showing the most rudimentary staminodes.
Anthers are tetrasporangiate, introrse, versatile, mostly dorsifixed (rarely basifixed, as in Spondias), and dehisce via longitudinal slits.
Gynoecium of the Anacardiaceae
The gynoecium is typically superior (or rarely partially to completely inferior) and consists of 1-5 (rarely to 12) carpels. In Anacardioideae, the ovary is predominantly pseudomonomerous and unilocular (derived from 3 fused carpels with only one fertile locule, or strictly monocarpellary, as in Mangifera). However, in the Spondiadoideae, the ovary is typically plurilocular with 4–5 (1–12) locules, except in Buchanania, which has up to 5 sterile carpels and only one fertile.
Styles range from 1 (terminal or lateral) to 3–5 (free or connate at the base). Stigmas are capitate, discoid, or lobed and are dry to wet and are often non-papillate.
Placentation is apical, basal, or parietal in unilocular forms, and axile/apical in plurilocular forms. There is strictly 1 ovule per locule (or 1 per fertile ovary). The ovule is anatropous, pendulous or ascending, bitegmic or unitegmic, and crassinucellate, bearing a dorsal or ventral raphe and lacking an aril.
Fruit of the Anacardiaceae
The fruit is usually an indehiscent drupe, which may be fleshy or dry and resinous. Wind-dispersed genera, however, produce winged samaras or samaroid fruits from accrescent floral parts. In some genera the pedicel or receptacle dramatically enlarges into a fleshy, edible accessory structure supporting the true fruit (as in Anacardium (cashew)).
The drupes possess a stony or cartilaginous endocarp containing 1 (Anaacradioideae) or 1-5+ (Spondiadoideae) locules and sometimes contain urushiol.
Seeds are non-endospermic or retain only a rudimentary endosperm.
Global Distribution of Anacardiaceae
The Anacardiaceae family is mainly tropical to subtropical, with a few important genera found in temperate North America. They are widespread pantropically and also in the Mediterranean, eastern Asia, and the warm Americas.
Distribution of Anacardiaceae in the Americas
Canadian AnacardiaceaeGenera
Anacardioideae in Canada
Cotinus 1 sp. intro to ON; Rhus 5 spp. native to all S provinces except NL; Toxicodendron 3 spp. native in all S provinces except NL, and including YT.
USA AnacardiaceaeGenera
Anacardioideae in the USA
Cotinus 2 spp. including 1 C+E USA endemic and 1 intro to UT, TX, OK, AR, IL, MO, AL, GA, TN, KY, OH, PA, NY, MD, DE, NJ, CT, MA, VT; Lithraea 1 sp. intro CA; Malosma monospecific S NAM endemic native CA; Mangifera 1 sp. intro to FL; Metopium 1 Gulf + Caribbean endemic sp. native to FL; Pistacia 3 spp, inc native in TX and 2 intro to CA, UT, OK, AL, GA, and VA; Rhus 16 spp. native and intro in the entire US, inc. HI; Schinus 5 former SAM endemic spp. intro to CA, TX, AL, FL, and HI; Searsia 1 sp. intro to CA and AZ; Sorindeia 1 sp. intro to FL; Toxicondrendon 5 spp. native in all the USA.
Spondiadoideae in the USA
Spondias 1 sp. intro to FL.
Mexico AnacardiaceaeGenera
Anacardioideae in Mexico
Actinocheita monospecific Mesoamerican endemic of Honduras and Nay, Jal, Col, Mch, Gro, Oax, and Pue; Amphipterygium 5 spp. native to most of Mexico except NW Mexico, including 2 endemics; Anacardium 1 sp. intro to Nay, Jal, Col, Mch, Gro, and Oax; Astronium 2 spp. native to most of Mexico exc. central and NW, inc. 1 narrow endemic of Ver; Bonetiella monospecific endemic of NE Mexico; Comocladia 5 spp. native in all of Mexico, inc. 3 endemic to Mexico; Cotinus 3 spp. native to Chi, Coa, NL, Tam, Dgo, Zac, Ags, Gto, Qro, and Hgo, including 2 endemics; Lithraea 1 sp. intro in Pue; Malosma monospecific S NAM endemic genus native to BCN, BCS, Son, Sin, Chi, Coa, NL, Tam, SLP, Dgo, Zac, and Mexican Pacific Islands; Mangifera 1 sp. intro SW+SE+C Mexico; Metopium 1 sp. native to Ver, Chp, Cam, Tab, Yuc, and QR; Mosquitoxylum monospecific N Neo endemic genus native to S Mexico in Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Tab, Cam, Yuc, and QR; Pachycormus monospecific endemic of BCN, BCS; Pistacia 2 sp. inc. 1 native to most of Mexico except BC, BCS, Son, and Sin and 1 intro to N Mexico; Pseudosmodingium 5 spp. endemic to most of Mexico exc. SE Mexico; Rhus 15+ spp. native throughout Mexico including the Mexican Pacific Is.; Schinus 2 former SAM endemic spp. intro N and SW Mexico; Toxicodendron 4 spp. native to all of Mexico.
Spondiadoideae in Mexico
Attilaea monospecific endemic of QR, Yuc, and Guatemala; Cyrtocarpa 3 spp. native to most of Mexico exc. Ver, inc. 2 endemics; Spondias 3 spp. native to all of Mexico; Tapirira 2 Mexico & neoendemic spp. native to SW Mexico, Pue, Ver, Cam, Tab, Yuc, and QR, including 1 endemic of Oax + Ver.
Neotropical AnacardiaceaeGenera
Anacardioideae in the Neotropics
Actinocheita monospecific Mesoamerican endemic native to Honduras; Amphipterygium 3 spp. native to Guatemala, Honduras, Nicaragua, and NW Costa Rica; Anacardium 13 spp. native from Honduras S to Peru, Bolivia, Paraguay, S Brazil, and also in Cuba and intro to the rest of the Antilles (exc. Netherlands Antilles & Aruba), Belize, and El Salvador; Apterokarpos (~Loxopterygium?) monospecific endemic to NE Brazil?; Astronium 10 spp. native to CAM S through tropical SAM to Peru, Bolivia, NE Argentina, S Brazil (4 endemics), and Trinidad-Tobago (1 endemic); Campnosperma 2 spp. native from Honduras S to Colombia, Venezuela, Ecuador, Peru, and Amazonian N Brazil; Cardenasiodendron monospecific endemic to Bolivia; Comocladia 24 spp. native to Guatemala, Belize, Greater Antilles, and Leeward & Windward Islands. with 15 single-island endemics of Jamaica (6), Hispaniola (5), Cuba (2), Dominican Republic, Haiti, and 1 extinct sp. of the Windward Is.; Haplorhus monospecific endemic to the dry inter-Andean valleys of Peru to N Chile; Lithraea 3 spp. SAM endemic genus of C+E+S Brazil, Bolivia, Paraguay, N Argentina, Uruguay, and C Chile, inc. 1 narrow endemic of C Chile; Loxopterygium 4 spp. SAM endemic genus of Venezuela, Guyana, Suriname, French Guiana, Ecuador, Peru, Bolivia, NW Argentina, and NE Brazil; Mangifera 1 sp. intro to Guatemala, Belize, Honduras, El Salvador, Costa Rica, Galapagos, Antilles (excluding Netherlands Antilles, Aruba), Venezuela, Ecuador, Peru, Paraguay, and S Brazil; Mauria 15 spp. neoendemic genus from Costa Rica S to Colombia, Venezuela, Ecuador, Peru, Bolivia, and NW Argentina; Metopium 4 spp. native to Guatemala, Belize, Honduras, the Bahamas, Turks and Caicos, the Antilles (except Leeward Is. & Venezuelan Antilles), and the SW Caribbean; Mosquitoxylum monospecific N neoendemic genus native to Jamaica, Guatemala, Belize, Honduras, Nicaragua, Panama, and Ecuador; Myracrodruon 2 spp. SAM endemic genus of Brazil, Bolivia, Paraguay, and N Argentina; Ochoterenaea monospecific N SAM endemic to Andean Venezuela, Colombia, and Bolivia; Orthopterygium monospecific endemic to W Peru; Pistacia 1 sp. native to Guatemala and Honduras; Rhus 1-3 spp. native to Cuba, Bahamas, Guatemala, El Salvador, Honduras, Nicaragua, and Costa Rica, and intro to Trinidad-Tobago; Schinopsis 7 spp. SAM endemic genus of Peru, Bolivia, C+E Brazil, Paraguay, and N Argentina; Schinus 40 spp. native to Peru, Bolivia, and C+E+S Brazil and all south, and intro to Ecuador, Colombia, Bermuda, the Bahamas, Turks and Caicos, Cuba, the Dominican Republic, Puerto Rico, Trinidad-Tobago, Venezuelan Antilles, Guatemala, and El Salvador; Semecarpus 1 sp. intro to Trinidad-Tobago; Thyrsodium 6 spp. N SAM endemic genus of Colombia, Peru, Bolivia, Venezuela, French Guiana, Guyana, Suriname, and N+C+E Brazil; Toxicodendron 3 spp. including 2 native to Bermuda, the Bahamas, Guatemala, El Salvador, Honduras, Nicaragua, Panama, Colombia, Venezuela, Ecuador, Peru, and Bolivia and 1 sp. intro to Cuba.
Spondiadoideae in the Neotropics
Antrocaryon 1 sp. endemic to Colombia and Amazonian N+C Brazil (the rest of the genera are tropical Africa); Attilaeamonospecific endemic to SE Mexico and Guatemala; Cyrtocarpa 2 spp. native to Colombia, Venezuela, Guyana, N+C+E Brazil, and the Netherlands Antilles; Dracontomelon 1 sp. intro to Trinidad-Tobago; Spondias 12 spp., including 11 natives of the Antilles, CAM S through tropical SAM S to Peru, Bolivia, and C+SE Brazil (6 endemics), and 1 sp. intro to Guatemala, Belize, Nicaragua, Panama, the Greater Antilles, Colombia, Venezuela, Guyana, French Guiana, N+SE Brazil, Ecuador, and Peru; Tapirira 8 spp. native from CAM S through tropical SAM to Peru, Bolivia, Paraguay, and S Brazil, including 3 narrow endemics of Costa Rica, Colombia, and French Guiana; Tumultivenia monospecific endemic of E + WC Brazil; Uniostium monospecific endemic of Colombia, Venezuela, Guyana, and the Netherlands Antilles.
Patagonia AnacardiaceaeGenera
Anacardioideae in Patagonia
Lithraea 1 SAM endemic spp. native to Bio Bio to Los Lagos in C. Chile; Schinus 6 former SAM endemic spp. native to the entire region.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, along with my own observations in North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Flora of North America (1993+). https://floranorthamerica.org/Main_Page.
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Neotropikey: Milliken, W., Klitgård, B. & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/ Retrieved Winter 2020-current.
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
18 Sep, 2022
13 Sep, 2022
How to Identify the Acanthaceae or Bear's Breeches Family
Tetramerium nervosum inflorescence with showy leaf-like hairy bracts and irregular flower. Page Last Updated August 28, 2026
Introduction to the Acanthaceae Family
When you learn to identify the Acanthaceae family, it helps to know that it is part of the Lamiales order of core eudicots and is closely related to the Lamiaceae, or mint family, with which it shares several characteristics. The Acanthaceae are widespread in tropical and subtropical regions, but the USA has quite a few, and they can even be found in temperate Canada.
What I love most about this family is their unique, often beautiful, and conspicuous bracts that surround their lovely flowers. Unsurprisingly, several species are used ornamentally, but others are also used medicinally. In the field, if you are injured, crush the leaves of most Acanthaceae and apply them directly to the wound to help healing.
Beginner’s Guide to the Bear’s Breeches Family
If you’re new to plant morphology, this guide is a perfect beginner’s description to learn about the Bear’s Breeches (Acanthaceae) family, with no need to know any scientific jargon. Below is additional information on uses and morphology, as well as pictures to help identify family members and individual species found in North America.
But for researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below the images in addition to genus-level distribution data.
Leaves and Stemsof the Bear’s Breeches Family
Most members are tropical herbs, shrubs, or climbing vines. Leaves are mostly simple (not compound) and arranged in opposite pairs along the stem, which often has swollen joints (nodes). Many species have mineral crystals (cystoliths) visible in their leaves and are covered with small hairs.
Flowersof the Bear’s Breeches Family
Flowers may be small or large and showy and are typically irregular in shape, often forming funnel-shaped flowers or two-lipped flowers where the petals are joined at the base into a tube. Flowers are almost always surrounded by large, showy, leaf-like structures called bracts, which are very characteristic of most members of the family.
Reproductive Featuresof the Bear’s Breeches Family
Most flowers contain both male and female parts (hermaphrodite or bisexual), with 2-4 stamens (male parts) attached inside the petal tube, often accompanied by smaller, sterile “fake stamens” (staminodes). The superior ovary (attached above the point of petal attachment) has a long, thread-like tube (style) on top to catch pollen and a nectary ring (hypogynous disk) at the base to attract pollinators.
Fruitsof the Bear’s Breeches Family
Fruits are almost always a dry, 2-chambered capsule that usually splits explosively when dry to scatter its seeds via small, hooked stalks (retinacula) attached to the seeds, aiding in their ejection from the fruit. However, in some taxa they are fleshy drupes (like a cherry) or leathery capsules that don’t split explosively.
Morphology of Acanthaceae in North America
Some Acanthaceae Species Found in North America
Acanthoideae Subfamily
Acanthus mollis—Bear’s Breeches
A clump-forming perennial herb with tuberous roots, a basal rosette of deeply lobed leaves, and tall spikes of pinkish or purplish flowers. Native to the Mediterranean, often cultivated in North America for its leaves and flowers.
Carlowrightia arizonica – Arizona Wrightwort
Heavily branched subshrubs are 10–30 cm tall, or sometimes taller. Leaves are simple, opposite, and variable in size and shape but approximately lanceolate. Flowers are narrowly triangular with 2 lateral petal lobes, 2 upper lobes fused with a yellow spot and purple streaks, and a keeled bottom lobe. Native to Texas, Arizona, California, and northern Mexico.
Dicliptera resupinata—Arizona Foldwing
An erect herb, up to 60 cm tall, with heavily branching, pubescent stems; the leaves are lanceolate, 2 – 6 cm long. Flowers are two-lipped, light purple with small dark purple lines near the center, and surrounded by two heart-shaped bracts. Native to southern AZ and NM, United States, and northwestern Mexico.
Justicia pilosella—Hairy Tubetongue
Herbaceous perennial to 30 cm tall with opposite leaves that may be pubescent or glabrous, but with ciliate margins and zygomorphic sessile flowers, with a long, white, pubescent tubular corolla with 4 pink or purple lobes, 3 of which bend outwards strongly. Narrowly endemic to southern TX and southern NM in the USA, plus arid northeastern Mexico.
Ruellia blechum—Green Shrimp Plant
Short herbaceous perennial that is erect or clambering, with opposite ovate leaves and a conspicuously pyramidal-shaped inflorescence, often with pilose pyramidal bracts and a conspicuous spike with pyramidal bracts. Native to Mexico, Central & South America. This one was from Paco’s Nature Reserve, Sinaloa, Mexico.
Ruellia caroliniensis – Carolina Wild Petunia
Unbranched herbaceous perennial to 1 m with opposite, oval leaves and sessile axillary clusters of 2 – 4 flowers with usually only 1 – 2 open at a time; leaves and flowers are crowded together at the top of the plant. Flowers are light purple to pinkish with a slender corolla tube and 5 petaloid lobes and long, pointed calyx lobes. Native throughout the eastern USA.
Ruellia humilis – Wild Petunia
Perennial herb up to 60 cm tall, with tubular, bell-shaped flowers with a long, skinny white tube and five shallow, rounded lavender to lilac-colored petals, singly or in clusters in upper axils, not crowded at the top of the plant. Native to the eastern and central USA.
Ruellia nudiflora – Violet Wild Petunia
An erect perennial, 30 – 60 cm tall, with few branches and opposite gray-green leaves 5 – 12 cm long, with wavy-toothed margins on short petioles. Terminal inflorescence of lavender to purple trumpet-shaped flowers (bractless, hence “nudiflora”) with inserted stamens. Native to the southern USA (AZ east to AL), Mexico, and Central America.
Ruellia strepens – Smooth Wild Petunia
An herbaceous perennial plant 0.5 – 1 m tall, sometimes branching, with hairless or sparsely hairy stems; opposite leaves up to 13 cm long, lanceolate to ovate, with smooth or slightly undulate margins and mostly hairless surfaces. Nearly sessile flowers in clusters of 1 – 3 in upper axils. Native to the south-central & southeast USA.
Tetramerium nervosum – Hairy Fournwort
Subshrub to 30 cm tall with opposite lanceolate leaves. Flowers in conspicuous pilose leafy bracts on hairy, 4-sided spike inflorescences; tubular with an upper lobe with a violet patch and a yellow base, 2 side lobes, and a keel-like lower lobe. Native to AZ and TX, USA, and south through Mexico and Central America to Venezuela.
Nelsonioideae Subfamily
Elytraria imbricata – Purple Scaly Stem
Weedy subshrub with linear leaves crowded at the top of the plant that may be basal and stemless or up to 60 cm tall. Inflorescences with very appressed bracts, blue flowers. Native from the southern USA to northern Argentina, mostly in dry tropical forests.
Thunbergioideae Subfamily
Thunbergia grandiflora – Blue Trumpet Vine
A twining evergreen vine 2 – 2.5 m long, with large, heart-shaped, bright green leaves and large, showy, lavender-blue, trumpet-shaped flowers up to 7 cm across with a yellow or white throat. Native throughout Southeast Asia. Often cultivated as an annual in North America.
Uses of the Acanthaceae
The leaves of many Acanthaceae are used externally for wounds, and recent research has shown that the family has antifungal, anti-inflammatory, antipyretic, antioxidant, insecticidal, immunomodulatory, anti-platelet aggregation, and antiviral potential. More research is currently underway.
Notable ornamentals include bear’s-breech (Acanthusmollis), clock vine (Thunbergia), shrimp plant (Justicia brandegeana), caricature plant (Graptophyllum pictum), and numerous others.
Ecosystem and Wildlife Values of Acanthaceae
The leaves of many Acanthaceae serve as primary larval hosts for several nymphalid butterflies, including the Common Buckeye, checkerspots, and more.
Many members have specialized pollination mechanisms that provide nectar for birds, bats, and specialist bees.
The mangrove genus Avicennia (Avicennioideae) acts as a foundational ecosystem engineer in intertidal marine and estuarine environments, ranking among the most carbon-dense ecosystems for carbon sequestration.
Taxonomy of Acanthaceae
The Acanthaceae family has 4605 species in 191 genera. It is part of the Lamiales order of the Core Eudicots. There are currently four recognized subfamilies of the Acanthaceae. Many more genera used to be present but have been submerged into Justicia, Ruellia, and others based on modern phylogenetics.
Acanthoideae Subfamily
The Acanthoideae are the largest subfamily by far, mostly made of herbs or sometimes shrubs, vines, or rarely trees. The presence of vascular bundles arranged in a circle in the petiole and the presence of cystoliths are nearly universal. The corolla often has the abaxial lobe outside the others when in bud, but it can also show contorted or imbricate variations. Anthers are sagittate, or the thecae are nonopposite and displaced, sometimes with one theca reduced, and the stigma is dry and typically bifid. Capsules are obovoid and almost universally explosive via retinacula with flattened seeds.
The Avicennioideae are trees with pneumatophores, sometimes stilt roots. The leaf lamina is thick with salt glands on both sides, club-shaped hairs, and colleters. Flowers are 4(-6) merous and quincuncial, with nectar glands on the inside of the tube. Stamens are equal and alternate with the corolla, and the stigma has two blunt lobes. The fruit is a fleshy or leathery capsule with 2 valves but is functionally single-seeded and exhibits cryptovivipary.
Genera of the Avicennioideae Subfamily
Avicennia (8).
Nelsonioideae Subfamily
The Nelsonioideae are mostly herbs with glandular hairs, though some are subshrubs or shrubs. The inflorescence may be terminal or axillary, bracts are spiral, and bracteoles are sometimes absent. The corolla exhibits descending cochleate aestivation with the adaxial lobes outside the others. There are 2 stamens, each with variable anthers, and the thecae may or may not be separate, or there may be 4 didynamous stamens, and the stigma is broadly lobed. An important feature is the lack of retinacula attached to the seeds and the absence of cystoliths, which separates them from most other members of the family.
The Thunbergioideae subfamily is mostly twining vines, but erect shrubs do occur. Petiole bundles are arcuate or annular with wing bundles. Leaf lamina venation is strongly curved, and like the Nelsonioideae, they lack cystoliths. The inflorescence consists of axillary or fasciculate flowers that lack bracts and have a strongly reduced calyx, but the bracteoles are very large, replacing the protective function of the calyx and may or may not be connate. The stigma is small, wet, sub-bilobed to trumpet-shaped, and has broad and often unequal papillate lobes. Unique to the family, some members produce fleshy, indehiscent drupes.
The Acanthaceae are most often confused with other families in the Lamiales order because they share opposite leaves and zygomorphic flowers.
However, the Lamiaceae can be differentiated by their aromatic essential oil glands and their absence of cystoliths and retinacula as well as their deeply 4-lobed ovary with a gynobasic style rather than the unlobed ovary with a terminal style in Acanthaceae.
The Verbenaceae are similar but can be differentiated by their lack of cystoliths and bracteoles and their fruits, which are fleshy drupes instead of the usually explosive capsules seen in the Acanthaceae.
Scientific Botanical Description of the Acanthaceae
This section is for researchers or others wanting a more in-depth scientific description to learn how to identify the Acanthaceae family.
Habit & Leaf Form of the Acanthaceae
The Acanthaceae are mostly tropical annual or perennial herbs (with or without a basal aggregation of leaves), shrubs, or stem twiners, root climbers, or scrambling vines, although some epiphytes or, rarely, small to medium leptocaul trees (with pneumatophores and sometimes stilt roots in Avicennia) are also seen. Branches are terete to angular in cross-section. Plants may be hydrophytic, helophytic (including a few mangroves), mesophytic (many from damp tropical forests), or xerophytic.
Leaves are simple and usually well developed but sometimes are much reduced, or occasionally plants are aphyllous switch-plants. Leaves may sometimes be heterophyllous and are often swollen at the nodes but lack stipules.
Leaves are arranged opposite, distichous, or decussate, and are rarely whorled. ), The lamina may or may not be gland-dotted; it is dissected or entire, pinnately veined, and cross-venulate. Lamina margins are entire, crenate, serrate, or dentate and may be flat, revolute, or involute. The leaf lamina is dorsiventral (sometimes incomplete) or bifacial (isobilateral in several genera), with or without epidermal salt glands, and the abaxial surface may be papillose.
Stomata are mostly diacytic (confined to the abaxial surface), but in Lepidagathis, they are paracytic and are variable in some basal taxa.
Diverse hairs are present, including eglandular, unicellular, uniseriate, glandular (may always be glandular in Nelsonioideae), and multicellular branched or simple. Cystoliths are very often present as streaks in the lamina.
Flowers of the Acanthaceae
Plants are almost always hermaphrodites, but dioecous and gynodioecius taxa do occur. Pollination is entomophilous, ornithophilous, or chiropterophilous and may be conspicuously specialized.
Flowers are solitary or, more often, aggregated in terminal or axillary racemes, cymes, thyrses, or often in dichasial cymes that are often condensed in the leaf axils; sometimes they are pseudanthial.
Flowers are subtended by bracts and paired bracteoles, which are often large, showy, or modified. In Thunbergioideae, bracts are absent or highly reduced, but paired bracteoles are still present. In Nelsonioideae, bracts are present, but bracteoles are sometimes absent.
Flowers are usually more or less zygomorphic, sometimes actinomorphic. They are tetracyclic, 4- or 5-merous, with a distinct calyx and corolla (2 whorls), and are predominantly zygomorphic, but sometimes actinomorphic or nearly so. A nectariferous hypogynous disk is present around the base of the ovary.
The calyx is 1-whorled and connate, typically 4-5 lobed via fusion of the anterior or posterior lobes. It is valvate or imbricate in bud, but in Thunbergia it is reduced to a truncate rim or multidentate ring.
The corolla is 1-whorled and connate, at least basally, with 4-5 lobes, ranging from tubular/infundibuliform to distinctly bilabiate or apparently 1-lipped when the upper lip is suppressed. Aestivation varies and is often diagnostic at the subfamily level and may be ascending cochlear (Nelsonioideae), descending cochlear (Acanthoideae), quincuncial (Avicennioideae), or contorted (Thunbergioideae and Acanthoideae).
Androecium of the Acanthaceae
The androecium has 2 or 4 (rarely 5) members that are epipetalous and alternipetalous, adnate, and usually inserted on the corolla tube and, when 4, are usually didynamous. Members may be equal or unequal, free of one another, or coherent and one whorled, exerted, or deeply included.
The androecium may consist entirely of fertile stamens or may include staminodes in the same series as the fertile stamens; stamens are often hairy, bearded, appendaged, or spurred.
Anthers may be separate from one another or connivent; they are dorsifixed or basifixed, dehiscing predominantly via longitudinal slits or rarely apical pores. They are typically tetrasporangiate but become monothecous or functionally unilocular through the reduction or abortion of one theca in some taxa.
Gynoecium of the Acanthaceae
The gynoecium is 2-carpelled, syncarpous, and superior, forming a sessile, 2-locular ovary (or rarely imperfectly 4-locular with false septa).
There is a single, slender, terminal, filiform style that arises, attenuated, from the ovary. longer than the ovary. The stigma is predominantly bifid with unequal lobes of the dry, non-papillate type, although they are wet and papillate with broad, often trumpet-shaped lobes in Thunbergioideae.
Placentation of the ovules is axile but may be apical or pendulous in Avicennia. Ovule numbers vary widely by lineage, with numerous (10-50+) per locule in Nelsonioideae and 2 to few, rarely up to 12, in the other subfamilies. Ovules are unitegmic, tenuinucellate, and anatropous to amphitropous/campylotropous. In core Acanthoideae, the funicle develops into a hardened, ossified hook (retinaculum).
Fruit of the Acanthaceae
The fruit of the Acanthaceae is usually a non-fleshy, 2-chambered loculicidal capsule that dehisces somewhat explosively via retinacula. In some species, fleshy drupes (some Thunbergioideae) or occasionally a compressed, leathery 2-valved capsule (Avicennioideae) are present.
Seeds are non-endospermic, may be conspicuously adorned with hairs, scales, or tubercules, and may contain starch.
Global Distribution of Acanthaceae
The Acanthanceae are mostly tropical and subtropical species, with a few temperate outliers. They are native and widespread throughout the tropical and subtropical latitudes in Africa, Australia, Indonesia, and the Americas.
Distribution of Acanthaceae in the Americas
Canadian AcanthaceaeGenera
Acanthoideae in Canada
Dianthera 1 sp. native to ON and QC (s/t included in Justicia); Justicia 1 sp. native in QC and ON.
USA Acanthaceae Genera
Acanthoideae in the USA
Acanthus 1 sp. intro to CA; Andrographis 1 sp. intro to VA; Anisacanthus 4 spp. native to AZ, NM, and TX; Asystasia 1 sp. intro to FL and AL; Barleria 2 spp. intro to FL; Carlowrightia 8 spp. native to CA, AZ, NM, and TX, and intro in FL; Dianthera 9 spp. including 8 native and 1 intro AZ, KS S to TX, and all E to NJ and S to FL from there plus IA, MI, NY, and VT (s/t included in Justicia); Dicliptera 4 spp. native to S half of USA from AZ E to NC and all S plus KS, MO, IL, IN, KY, and VA; Dyschoriste 6 spp. native to NM, AZ, TX, LA, OK, FL, AL, GA, and SC; Eranthemum 1 sp. intro to FL; Graptophyllum 1 sp. intro to FL; Hemigraphis 2 spp. intro to LA and FL; Henrya 1 sp. native to AZ; Hygrophila 6 spp. native and intro to TX, LA, AL, MS, GA, FL, and VA; Hypoestes 1 sp. intro to HI; Justicia 19 spp. native and intro in most of S half USA CA E to NJ and all S exc NV, UT, CO and inc IA, WI, MI, NY, and VT; Megaskepasma monospecific, formerly N SAM endemic, introduced in HI; Odontonema 2 spp. intro to AL and FL; Pseuderanthemum 1 sp. intro to FL and SC; Ruellia 22 spp. native in most of E half USA from ND S to TX and all E exc. ND, SD, CT, RI, MA, VT, NH, ME, and including AZ and NM, but intro in AK and NY; Sanchezia 1 former neoendemic sp. intro to HI; Stenandrium 2 spp. native in NM, TX, FL, and GA; Strobilanthes 1 sp. intro LA and FL; Tetramerium 1 sub & tropical Americas endemic sp. native to NM, AZ, and TX; Yeatesia 2 SE NAM endemic spp. native to TX, LA, AL, MS, FL, and GA.
Avicennioideae in the USA
Avicennia 2 of 8 pantropical spp. native to TX, MS, AL, GA, LA, and FL and introduced to CA.
Nelsonioideae in the USA
Elytraria 3 spp. native to NM, AZ, TX, FL, GA, and SC, including 1 narrow endemic to GA, FL, and SC; Nelsonia 1 sp. intro to FL.
Thunbergioideae in the USA
Thunbergia 5 spp. intro in TX, FL, and HI.
Mexico AcanthaceaeGenera
Acanthoideae in Mexico
Acanthus 1 sp. intro to Pue; Andrographis 1 sp. intro to Pue, Tlx, Mor, and Ver; Anisacanthus 7 spp. native throughout all of Mexico, including 3 endemic to Mexico; Aphanosperma sinaloensis monospecific endemic to BC, BCS, Son, Sin, Chi, Dgo, Zac, NL, and Tam; Aphelandra 11 spp. native throughout all of Mexico, including 5 endemics; Barleria 1 sp. native to most of Mexico except BC, BCS, Son, and Sin; Bravaisia 3 Mexico + N neoendemic spp. native to much of Mexico except BC, BCS, Son, and Sin; Buceragenia 2 unplaced narrow endemics of C Mexico; Carlowrightia 26 spp. native throughout all of Mexico, including 15 endemics of Mexico, 7 of which are narrow endemics of Tam (3), Chi (2), Sin, and Yuc; Chalarothyrsus monospecific endemic of Nay, Jal, Col, Mch, Gro, Oax, and Pue; Chileranthemum 3 spp. native to most of Mexico except BC, BCS, Son, and Sin, and includes 1 narrow endemic of Jal + Gro; Dianthera 6-8 spp. native throughout all of Mexico, s/t included in Justicia now; Dicliptera 15 spp. native to all of Mexico; Dyschoriste ~20 spp. native throughout all of Mexico; Gypsacanthus monospecific endemic to Nay, Jal, Col, Mch, Gro, Oax, and Pue; Henrya 3 Americas endemic spp. native in all of Mexico, including 2 endemic to S+W Mexico; Holographis 18 spp. endemic genera found throughout all of Mexico; Hoverdenia monospecific endemic to Chi, Coa, NL, SLP, Dgo, Zac, and Ver; Hygrophila 2 spp. inc., 1 native and 1 intro to Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Yuc, QR, Cam, and Tab; Hypoestes 1 sp. intro to much of Mexico exc BC, BCS, Son, Sin, Cam, Tab, Chp, Yuc, and QR; Justicia 20+ spp. native throughout all of Mexico; Lepidagathis 1-2 spp. native to Nay, Jal, Col, Gro, Mch, Oax, Chp, Pue, Mor, Ver, Cam, Tab, Yuc, and QR; Louteridium 9 Mexico + neoendemic spp. native to most of Mexico except BC, BCS, Son, and Sin, including 6 narrow endemics of Mch, Oax, Jal + Mch, Ver + Chp, Gro, and Tam; Mexacanthus monospecific endemic of Nay, Jal, Col, Mch, Gro, and Oax; Mirandea 6 Mexico endemic spp. native to most of Mexico except Pue, BC, BCS, Son, and Sin; Odontonema 4-7 spp. native in all of Mexico; Pachystachys 1 neoendemic sp. native to Chp, Cam, Tab, QR, and Yuc, and intro to Nay, Jal, Col, Gro, Mch, and Oax; Poikilacanthus 5 Mexico + neoendemic spp. native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Pue, Tab, Cam, Yuc, and QR, including 4 endemic to Mexico; Pseuderanthemum 5-8 spp. native throughout all of Mexico; Ruellia ~50+ spp. native throughout all of Mexico, including ~20 endemic species; Sanchezia 1 former neoendemic sp. intro to Chp, Tab, Cam, Yuc, and QR; Spathacanthus 3 Mexico + CAM endemic spp. native to Nay, Jal, Col, Mch, Gro, Pue, Ver, Chp, Tab, Cam, Yuc, and QR, including 1 narrow endemic of Ver; Stenandrium 8-10 spp. native throughout all of Mexico; Stenostephanus 15 Mexico + neoendemic spp. native to most of Mexico except BC, Son, and Sin; Streblacanthus 2 Mexico & N neoendemic spp. native to Nay, Jal, Col, Mch, Gro, Oax, and Ver; Tetramerium ~25 sub & tropical Americas spp. native in all of Mexico, including 21 endemics of Mexico; Yeatesia 3 SE NAM endemic spp. native to Chi, Coa, NL, Tam, Dgo, Zac, SLP, Hgo, and Mex, including 1 endemic of NE Mexico.
Avicennioideae in Mexico
Avicennia 2 spp. native to most of Mexico except C. Mexico.
Nelsonioideae in Mexico
Elytraria 4 spp. native to all of Mexico, inc. Mexican Pacific Is., including 2 endemics to Mexico; Nelsonia 1 sp. intro to Nay, Jal, Col, Gro, Mch, and Oax; Staurogyne 1 sp. native to Nay, Jal, Col, Mch, Gro, and Oax.
Thunbergioideae in Mexico
Mendoncia 3 spp. native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Tab, Cam, Yuc, and QR; Thunbergia 3 spp. intro to much of Mexico except BC, BCS, Son, and Sin.
Neotropical AcanthaceaeGenera
Acanthoideae in the Neotropics
Acanthus 1 sp. intro to Costa Rica; Ancistranthus monospecific endemic to Cuba; Andrographis 1 sp. intro to Bahamas, Cuba, Hispaniola, Leeward & Windward Is.; Anisacanthus ~9 spp. native to El Salvador, Honduras, Nicaragua, Costa Rica, E Brazil, inc. 5 narrow endemics of Nicaragua, Costa Rica, and E Brazil (3); Aphelandra 212 spp. native from Mexico S through CAM, Trinidad-Tobago, tropical SAM S to Peru, N Argentina exc. N Chile, Paraguay, and Uruguay, and intro in Cuba, Dominican Republic, and Windward Is.; Asystasia 2 spp. intro to Cuba, Belize, El Salvador, Honduras, Nicaragua, Antilles (exc. Netherlands Antilles), Venezuela, and SE Brazil; Barleria 1 sp. native to CAM, Colombia, Venezuela, Guyana, intro Bahamas, Antilles (exc. Cayman Is.), SW Caribbean, Trinidad-Tobago, French Guiana, and S Brazil; Barleriola 4 spp. Greater Antilles endemic genus of Cuba, Dominican Republic, Haiti, and Puerto Rico; Bravaisia 3 spp. native to CAM, Cuba, Colombia, Venezuela, and Trinidad-Tobago and intro to Venezuelan Antilles and Windward Is.; Brillantaisia 1 sp. intro Jamaica; Carlowrightia 4 spp. native to CAM (except Panama) and includes 1 narrow endemic in Ecuador; Cephalacanthus monospecific endemic of Peru; Chamaeranthemum 4 spp. neoendemic genus of Costa Rica, Peru, and SE+S Brazil, including 3 narrow endemics of Costa Rica (2) and Rio de Janeiro, SE Brazil; Chileranthemum 2 spp. native to Guatemala and El Salvador; Clistax 3 spp. endemic to N+E+S Brazil; Crossandra 1 sp. intro to the Antilles (except Cayman Is. and Netherlands Antilles), El Salvador, and Nicaragua; Cuenotia monospecific endemic of NE Brazil; Cyphacanthus monospecific endemic to Colombia; Dasytropis monospecific endemic to Cuba; Dianthera ~36 spp. native to CAM, the Antilles (exc. Cayman Is. & Netherland Antilles), and S through tropical SAM S to N Argentina (exc. N Chile), and intro Bermuda; Dichazothece monospecific endemic of SE Brazil; Dicliptera 20+ spp. native to CAM, Bahamas, Turks-Caicos, Greater Antilles (except Cayman Is.), Leeward & Windward Is., Trinidad-Tobago, and tropical SAM S to N Chile and N Argentina; Dyschoriste ~45 spp. native to CAM (except Belize), Cuba, Hispaniola, Venezuela, Ecuador, Peru, Bolivia, Paraguay, C+S+SE Brazil, N Argentina, and Uruguay, and intro Leeward Is.; Encephalosphaera 3 spp. N SAM endemic genus of Colombia, Ecuador, Peru, and N Brazil; Eranthemum 1 sp. intro to El Salvador, Antilles (excluding Puerto Rico, Netherlands Antilles, and Cayman Is.), Trinidad-Tobago, and Suriname; Fittonia 2 spp. native to Colombia, Venezuela, Ecuador, Peru, Bolivia, and N Brazil and intro to El Salvador and Trinidad-Tobago; Graptophyllum 1 sp. intro to Cuba, Hispaniola, Puerto Rico, Jamaica, Leeward Is, Venezuelan Antilles, Trinidad-Tobago, Honduras, Nicaragua, Panama, and Venezuela; Harpochilus 2 spp. narrow endemic genus of NE Brazil; Henrya 1 sp. native to CAM (excluding Belize); Herpetacanthus 21 spp. neoendemic genus of Costa Rica, Honduras, Nicaragua, Panama, Ecuador, French Guiana, Suriname, Peru, Bolivia, and N+E Brazil; Hygrophila 2-3 spp. native and intro to the Greater Antilles (exc. Cayman Is.), Trinidad-Tobago, CAM (exc. Costa Rica), and tropical SAM S to N Argentina (exc. N Chile); Hypoestes 1 sp. intro in Guatemala, El Salvador, Honduras, Panama, Colombia, and Paraguay; Isotheca monospecific endemic to Venezuela and Trinidad-Tobago; Justicia ~500 spp. native and widespread in CAM, Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., Trinidad-Tobago, and tropical SAM S to N Argentina (exc. N Chile); Kalbreyeriella 4 spp. neoendemic genus native to Costa Rica, Panama, Colombia, N Brazil, Ecuador, and Peru; Lankesteria 1 sp. intro to Trinidad-Tobago; Lepidagathis ~50-60 spp. native to CAM, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is., Trinidad-Tobago, tropical SAM S to Peru, NW Argentina, Paraguay, and S Brazil; Liberatia 2 spp. SAM endemic genus of SE+S Brazil (not in APG); Louteridium 5 spp. native to CAM (exc. El Salvador), including 1 narrow endemic of Belize; Megaskepasma monospecific genus native to Suriname and Venezuela, now introduced in Costa Rica, Nicaragua, Panama, and Trinidad-Tobago; Morsacanthus monospecific endemic of S Brazil; Neriacanthus monospecific single-island endemic of Jamaica; Odontonema 32 spp. native from Mexico S through CAM, Cuba, Haiti, Leeward & Windward Is., Trinidad-Tobago, Ecuador, Colombia, Venezuela, N+E Brazil, and Guyana, and intro to Paraguay, the Dominican Republic, Puerto Rico, and Galapagos; Oplonia 16 spp. mostly neoendemic genus native to the Bahamas, Turks and Caicos, Cuba (8 endemics), Hispaniola, Jamaica (3 endemics), Puerto Rico, the Leeward Islands, Peru (2 endemics), Bolivia, and NW Argentina; Orophochilus monospecific endemic of Peru; Pachystachys 18 spp. native from S Mexico, Costa Rica, Panama, Cuba, Lesser Antilles (exc. Netherlands Antilles), and tropical SAM S to N Argentina (exc. Suriname, N Chile, and Uruguay), and intro Guatemala, El Salvador, Hispaniola, and Puerto Rico; Phaulopsis 1 sp. intro to Colombia and Jamaica; Phlogacanthus 1 sp. intro to Windward Is.; Poikilacanthus 9 spp. native to Guatemala (2 endemic), Honduras, Nicaragua, Panama, Venezuela (1 endemic), Peru (1 endemic), Bolivia, E+S Brazil (2 endemics), Paraguay, Uruguay, and N Argentina; Pranceacanthus monospecific endemic of N+C Brazil and Bolivia; Pseuderanthemum ~60 spp. native to CAM, Colombia, Venezuela, Brazil, Ecuador, Peru, Bolivia, intro Cuba, Puerto Rico, Leeward & Windward Is., Venezuelan Antilles, and Trinidad-Tobago; Psilanthele monospecific endemic to Ecuador; Pulchranthus 4 spp. N SAM endemic genus of Colombia, Venezuela, N Brazil, Suriname, French Guiana, Ecuador, Peru, and Bolivia; Rhombochlamys monospecific endemic of Colombia; Ruellia ~300 spp. native to CAM, Bahamas, Turks-Caicos, Aruba, Antilles (exc. Netherlands Antilles), Trinidad-Tobago, SW Caribbean, Galapagos, and tropical SAM S to N Argentina (exc. N Chile); Ruspolia 1 sp. intro to Trinidad-Tobago; Salpixantha monospecific endemic of Jamaica; Samuelssonia monospecific endemic of Haiti; Sanchezia 55 spp. native to Panama, Colombia, Venezuela, N Brazil, Ecuador, Peru, and Bolivia, and now intro to Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica, Antilles (exc. Cayman Is, Netherlands Antilles), and Trinidad-Tobago; Sapphoa 2 spp. endemic genera of Cuba; Schaueria 15 spp. formerly endemic to C+E+S Brazil, but 1 sp. now intro in Trinidad-Tobago; Sebastiano-schaueria monospecific endemic to SE Brazil; Spathacanthus 3 spp. native to Guatemala, Honduras, and Costa Rica (1 endemic); Stenandrium 35-40 spp. native from S USA to Nicaragua (exc. Belize), plus Bahamas, Turks-Caicos, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is., and tropical SAM S to C Chile, N Argentina (exc. Guyana, Suriname, French Guiana, N Chile); Stenostephanus 95 spp. native from Mexico S through CAM (exc. Belize, El Salvador) to Colombia, Venezuela, N+SE Brazil, Ecuador, Peru, and Bolivia; Streblacanthus 3 spp. native to Guatemala, Costa Rica, Panama, Peru, and N Brazil; Strobilanthes 1 sp. intro to Belize, El Salvador, Honduras, Nicaragua, Panama, Cuba, Hispaniola, Jamaica, Puerto Rico, Windward Is., Venezuelan Antilles, and Trinidad-Tobago; Suessenguthia 8 spp. N SAM endemic genus of N Brazil, Peru, and Bolivia; Tetramerium 9 spp. native to Guatemala, El Salvador, Honduras, Nicaragua, Panama, Venezuela, Colombia, Ecuador, Peru (5 endemics), and Bolivia; Trichanthera 2 spp. neoendemic genus of Panama, Colombia, Venezuela, N Brazil, Guyana, Suriname, French Guiana, Ecuador, and Peru; Trichosanchezia monospecific endemic of Peru; Xantheranthemum monospecific endemic of Peru.
Avicennioideae in the Neotropics
Avicennia 3 spp. native to CAM, Bahamas, Aruba, Turks and Caicos, Antilles, SW Caribbean, Trinidad-Tobago, Colombia, Venezuela, Guyana, Suriname, French Guiana, N, E, and S Brazil, Uruguay, Ecuador, and Peru.
Nelsonioideae in the Neotropics
Aymoreana monospecific narrow endemic of E Brazil; Elytraria 11 spp. native to CAM, Cuba (6 endemics), Haiti (1 endemic), Aruba, Trinidad-Tobago, and tropical SAM S to Ecuador (1 endemic), Peru (1 endemic), NW Argentina, C+SE Brazil, and intro to Galapagos; Nelsonia 1 sp. intro to El Salvador, Honduras, Nicaragua, Panama, Puerto Rico, Colombia, Ecuador, French Guiana, Bolivia, and N+C+E Brazil; Staurogyne 28-30 spp. native from Nicaragua S to Colombia, Venezuela, Guyana, Suriname, French Guiana, Brazil, Bolivia, and Trinidad and Tobago.
Thunbergioideae in the Neotropics
Mendoncia ~74 spp. native to CAM (exc. El Salvador), Trinidad-Tobago, and tropical SAM S to Peru, Bolivia, Paraguay, and S Brazil; Thunbergia several spp. intro to Bahamas, Antilles (exc. Cayman Is., Netherlands Antilles), CAM (exc. Nicaragua), and tropical SAM S to N Argentina (exc. French Guiana, N Chile, and Uruguay).
Patagonia Genera Include:
Acanthoideae in Patagonia
Stenandrium 1 sp. native in Bio Bio in C Chile and also in Buenos Aires, Argentina, just N of Patagonia.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, as well as my own personal observations of species in North America.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Flora of North America. (1993+). https://floranorthamerica.org/Main_Page.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/ Retrieved Winter 2020 – present.
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout the fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
13 Sep, 2022
9 Sep, 2022
How to Identify the Araceae or Arum Family
Arisaema triphyllum flowers in a spadix enclosed in a sheath, typical of the Araceae family. Page Last Updated August 28, 2026
Introduction to the Araceae Family
When you learn to identify the Araceae family, first understand that it is part of the Alismatales order of basal monocot flowering plants. As a monocot, they typically have parallel veins in their leaves. However, as a basal monocot, they diverged early in evolution, so their flowers are atypical for monocots. However, their very small size and dense packing into a spadix, enclosed by a showy spathe, make them easy to recognize in the field.
The Araceae family has always been a favorite of mine, having grown up in the temperate rainforest of the British Columbia coast of western Canada, where skunk cabbage is often found in wet forests and swamps. Most people don’t like the smell, hence the name; however, I love the smell because I love swamps and stinky plants, and when I smell skunk cabbage, odds are there is a swamp for me to explore! I love it so much I even have it tattooed on my back!
Beginner’s Guide to the Arum (Araceae) Family
If you’re new to plant morphology, this guide is a perfect beginner’s description to learn to identify the Araceae family, with no need to know any scientific jargon. Below is additional information on uses and morphology, as well as pictures to help identify family members and individual species found in North America.
But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Description below the images for highly detailed scientific descriptions and genus-level distribution data.
Leaves and Stems of the Arum Family
Perennial herbs, shrubs, or vines; some are aquatic plants, some terrestrial, and others grow on trees (epiphytes). They often lack true stems and instead frow from underground corms, rhizomes, or above-ground runners. Leaves are arranged spirally or alternately; most have stalks (petioles) and a base that sheaths or wraps around the plant. Leaves may be simple or compound, and they may contain natural holes. They often contain a milky or watery sap.
Flowers of the Arum Family
Unique tiny flowers densely packed in a cylindrical structure called a spadix are the most characteristic feature of this family, which makes them easy to identify. The spadix is almost always accompanied by a spathe, which is a large leaf-like bract that may be green or brightly colored and may persist or fall off. The flowers often emit strong, foul odors to attract pollinators.
Reproductive Features of the Arum Family
Some species have bisexual flowers with male (stamens) and female (ovary, style, and stigma) parts in the same flower, while others have separate male and female flowers on the same spike (monoecious), usually with males on top and female flowers below. But the flowers are very tiny, and a hand lens would be needed to see any detail.
Fruits of the Arum Family
Fruits are usually fleshy berries with one to several seeds. Occasionally the berries merge into a single compound fruit.
Morphology of Araceae in North America
Some Araceae Species Found in North America
Aroideae Subfamily
Arisaema dracontium—Green Dragon
Herbaceous perennial with one leaf that is compound and divided into two leaflets that are again palmately divided into 5 – 15 leaflets each. Flowers are in a very spadix that sticks out well beyond the sheath, several inches or more. This Araceae member is native to eastern North America, including northeastern Mexico.
Arisaema quinatum or A. triphyllum ssp. quinatum—Southern Jack-in-the-Pulpit
Herbaceous perennial with 3 leaflets per leaf, but the lateral leaflets are deeply 2-lobed, making it look like it has 5 leaflets. Flowers in a spadix enclosed by a fleshy, hooded sheath. Endemic in the southeastern USA, from Texas east to North Carolina.
Herbaceous perennial with trifoliate compound leaves on long petioles from the ground up. Flowers are in a narrow spadix enclosed by a green or purplish hooded sheath. Flowers are in a thin green spadix that is closed by a hooded sheath. Native to eastern North America.
Arum italicum—Italian Arum
Herbaceous perennial with large, showy, sagittate leaves and a large white or yellow spathe that surrounds its white to reddish spadix. Native to the Mediterranean and cultivated in North America.
Calla palustris—Bog Arum
An aquatic perennial with rounded to cordate leaves, 6 – 10 cm long and nearly as wide, on a 10 – 20 cm petiole. The flowers are enclosed by a white sheath and grow in a greenish-yellow spadix. Fruit is a cluster of red berries. Native to cool, temperate areas of the Northern Hemisphere. These plants were found in a roadside ditch in Midland, MI, USA.
Colocasia esculenta—Taro
Herbaceous perennial with an edible corm and large sagittate leaves on long, thick petioles. Spreads vegetatively and rarely flowers. Native to tropical eastern Asia, it has been introduced to North America, where it has become invasive. This was in Hot Springs, AR, USA
Peltandra virginica – Green Arrow Arum
Mostly aquatic herbaceous perennials with large sagittate leaves and pale green to white inflorescences enclosed in a darker-colored spathe. Grows in wet, swampy areas. Native to eastern North America.
Lemnoideae Subfamily
Lemna minor—Common Duckweed
A tiny floating aquatic plant with two (1-4) small leaves and a single free-floating root. It spreads vegetatively, and flowers are rare and inconspicuous. This plant has a cosmopolitan distribution.
Orontioideae Subfamily
Lysichiton americanus—Skunk Cabbage
An herbaceous perennial of wet, soggy soils and swampy areas. It has large sessile ovate leaves and a large yellow spathe encasing a rough greenish-yellow spadix. Has a strong skunky odor. This lovely but often misjudged Araceae member is native to northwest North America.
Pothoideae Subfamily
Anthurium andraeanum – Painter’s Palette
A tropical perennial plant that is often cultivated as a house plant. It has colorful orange to reddish spathes that do not enclose the yellow spadix. It is native to Colombia & Ecuador but widely cultivated as a tropical houseplant.
Uses of the Araceae
Many Araceae are toxic due to the presence of calcium oxalate crystals, which can irritate the digestive tract when ingested. Despite these concerns, however, many are still important food sources in tropical regions, including Alocasia, Amorphophallus, Colocasia esculenta (taro), Monstera, and Xanthosoma sagittifolium.
Some are used as traditional herbal medicines, or their roots are used for fiber or arrow poisons.
Many genera are cultivated worldwide as ornamentals both outdoors and indoors as houseplants, including Dieffenbachia, Caladium, Philodendron, Zantedeschia, and many more.
The Araceae also include unique plants such as Amorphophallus titanum, which has the most massive inflorescence in all the angiosperms, and Wolffia species, which have the smallest flowers.
Ecosystem and Wildlife Values of the Araceae
The berries of the Araceae serve as high-energy food sources for birds who ingest them and disperse the seeds, while neotropical frugivorous bats feed heavily on the fruits of climbing aroids, and numerous terrestrial rodents, mammals, and primates dig and eat the carbohydrate-rich tubers.
Free-floating Lemnoideae are exceptionally protein-rich food sources, providing primary forage for waterfowl, herbivorous fish, semi-aquatic rodents, and aquatic invertebrates.
Many large-spathed genera produce thermogenic heat to volatilize foul scent compounds, which creates a warm microclimate that traps and sustains pollinating beetles and flies overnight.
Taxonomy of Araceae
There are approximately 3,667 to 6,500 species in the Araceae family across 143 genera and currently eight accepted subfamilies, which are undergoing revisions and may change in the future. This family is part of the Alismatales order, which is considered a basal monocot and diverged early in monocot evolution.
Aroideae Subfamily
The Aroideae have highly variable growth forms, making generalizations difficult. But they are unisexual, typically monoecious plants with flowers that lack a perianth. They have tiny staminate flowers with connate stamens or free stamens with a thick connective found at the top of the spadix. Their pistillate flowers are found below the staminate ones on the spadix, and they often have staminodes. Their distribution is cosmopolitan.
The Gymnostachyoideae are the earliest-diverging sister lineage to other Araceae. It is a monospecific family with leaves that are two-ranked and linear and parallel-veined, with minute teeth, especially near the tip, and there is no distinction between the blade and petiole. Unlike other Araceae, it produces bisexual flowers possessing a perianth and arranged in numerous spicate spadices subtended by small, leafy bracts in a large branched inflorescence. These are restricted to eastern Australia.
Genera of the Gymnostachydoideae Subfamily
Gymnostachys (1).
Lasioideae Subfamily
The Lasioideae are often robust, prickly, rooted aquatic or perennial herbs. Their petioles are long, warty, aculeate, or brightly colored, and their spathe is often spirally twisted. Their flowers may or may not have a perianth, and they have variable stamens, usually 4-6 but up to 12, with broad, short filaments and extrorse anthers with short apical or oblique pore-like slits. They are found pantropically.
The Lemnoideae are all highly reduced, small, floating aquatic herbs with 0-5 unbranched hairless roots. They are made of thalloid stem-leaf units that possess only a primary vein without any vascular tissue. They have no perianth and possess only one stamen and one gynoecium. They have a cosmopolitan distribution.
The Monsteroideae are herbs, climbers, and epiphytes. Their flowers are bisexual, the pollen is inaperturate, the style has abundant trichosclereids, and ovules (1-4, -many) per carpel are often basal or sometimes hemianatropous. Most members lack a perianth, but some retain one. Their distribution is pantropical.
The Orontioideae subfamily is a variable group that has no vessels, possesses biforine raphides (exc. Lysichiton), has leaf blades with a midrib (exc. Orontium), and has bisexual flowers with usually inferior ovaries (exc. Orontium), a perianth of tepals, and may or may not have styles. Their distribution is north temperate.
Genera of the Orontioideae Subfamily
Lysichiton (2), Orontium (1), and Symplocarpus (6).
Pothoideae Subfamily
The Potthoideae have a flat, strap-shaped, or reflexed spathe that does not enclose the spadix and is persistent in the fruit, and they may have winged, flattened, photosynthetic petioles that may dwarf the leaf blade. They have bisexual flowers with usually 4 tepals in 2 whorls, 4 free stamens with flattened filaments, and the ovules are basally or parietally placentated. Distribution is pantropical, excluding Africa.
Genera of the Pothoideae Subfamily
Anthurium (1459), Pothoidium (1), and Pothos (66).
Zamioculcadoideae Subfamily
The Zamioculcadoideae are rhizomatous or tuberous plants with leaves that are usually 1-3-compound or simple in Stylochaeton. Leaf fine venation is reticulate, and the leaves are characteristically pulvinate along the petiole or petiolules. They are monoecious, having staminate and pistillate flowers on the same spadix. Placentation of ovules is axile, and there is one ascending ovule per carpel. Their native distribution is restricted to Africa.
The Araceae are easily differentiated from similar families with their spadix of numerous small flowers with their unique subtending spathes, their leaves with either parallel or netted venation (unlike only parallel in most monocots), their raphide crystals, and their seeds with endosperm.
The Acoraceae (sweet flags) were formerly placed in this family, but they can be differentiated by their unifacial, ensiform leaves, parallel venation, aromatic essential oils, and the lack of calcium oxalate raphide crystals.
The Alismataceae share the same aquatic habitats and sometimes sagittate leaves with reticulate venation, but they possess distinct 3-merous showy flowers with perianths, and they are not arranged in dense, fleshy spadices.
Scientific Botanical Description of the Araceae
Habit & Leaf Form of the Araceae
The Araceae are perennial herbs, shrubs, or vines that may be aquatic or terrestrial, emergent or floating, or epiphytic. They grow from vertical or horizontal rhizomes that may or may not be branched, starchy underground corms, or stolons found at or near the surface. Roots are often mycorrhizal and have no root hairs. They usually do not possess typical stems, but some taxa do. Plants always have calcium oxalate crystals or raphides and have laticifers that produce a milky, watery, or rarely colored latex.
Leaves may appear before or after the inflorescence, and cataphylls are often seen. Leaves are alternate, bifacial, spiral, distichous, or rarely solitary. A petiole is almost always present, and bases are sheathing with a membranous sheath. The leaf blade is simple or compound and sometimes is perforated or fenestrated. Leaf shape is elliptic to obovate or spatulate and sometimes sagittate–cordate. Venation can be parallel, pinnate-netted, or palmate-netted.
Flowers of the Araceae
Araceae plants are often monoecious and may be hermaphroditic or rarely dioecious. The inflorescence is characteristic of the family, with a terminal cylindrical or ovoid spadix on a peduncle bearing 3-900 sessile flowers that are very tightly packed together. When monoecious, the male flowers appear on the upper part of the spadix, with the female flowers below.
The spadix is almost always subtended by a persistent or deciduous spathe that is often colored. In the Lemnoideae, the spadix is reduced to 1–4 flowers, which are in a pouch.
Flowers are small, sessile, actinomorphic, ebracteate, hypogynous with superior ovaries (except in Orontioidiae, where the ovaries may be inferior or semi-inferior), and often possess a strong odor that most find unpleasant.
The perianth is usually only present in bisexual flowers, while most monoecious flowers and some bisexual flowers in the Monsteroideae are lacking perianth altogether. When present, the perianth is 2-whorled with 4-6 (rarely up to 9) parts that may be free or basally joined.
Androecium of the Araceae
The androecium has 4, 6, or 8 (1-32) members arranged opposite the tepals in flowers that possess a perianth. Stamens may or may not all be fertile; staminodes are often present and serve structural or secretory roles. Stamens may be free or connate in Synandria.
Anthers are often subsessile with short, flattened, or nearly absent filaments and a thick and fleshy connective tissue. Dehiscence is poricidal, longitudinal, or transverse.
Gynoecium of the Araceae
The gynoecium is syncarpous with one ovary that is 1-3 (or many) locular and may be sessile or embedded in the spadix. The ovary is usually superior with as many locules as carpels (no false septa), except when embedded in the spadix.
There is usually one short, stout style (sometimes absent) with a hemispheric, capitate, or discoid stigma that is sometimes strongly lobed. Placentation is highly variable and helps differentiate at the subfamily and tribe level and may be parietal, axile, basal, or apical. Ovules are one to many per carpel and are usually anatropous and bitegmic.
Fruit of the Araceae
The fruits of the Araceae are one- to many-seeded indehiscent berries that may be distinct or, less often, connate in a syncarp. Rarely do the fruits form as dehiscent berries via a stylar plate.
Seeds are variable in shape, may or may not possess endosperm, are oily and sometimes starchy, and sometimes have a fleshy seed coat.
Global Distribution of Araceae
The Araceae are most diverse in the neotropics of the Americas, but they are also found in the Old World tropics and in temperate regions, especially in the northern temperate zones.
Distribution of Araceae in the Americas
Canadian AraceaeGenera
Aroideae in Canada
Arisaema 2 spp. native to MB, ON, QC, NB, NS, and PE; Arum 1 sp. intro to BC; Calla 1 pan-north temperate sp native to all of Canada except NT; Peltandra 1 E NAM (+Cuba) endemic sp. native to ON and QC; Pinellia 1 sp. ephemeral intro ON; Pistia 1 pantropical sp. intro to ON.
Lemnoideae in Canada
Lemna 6 of 18 cosmopolitan spp. native to all of Canada except NF, where it was introduced; Spirodela 1 cosmopolitan sp. native to BC, AB, SK, MB, ON, QC, NB, NS, and PE; Wolffia 4 cosmopolitan spp., including 3 native to BC, AB, SK, MB, ON, QC, and NB and 1 intro in ON.
Orontioideae in Canada
Lysichiton 1 sp. native to BC; Symplocarpus 1 E NAM endemic sp. native to ON, QC, NB, and NS.
USA AraceaeGenera
Aroideae in the USA
Aglaonema 1 sp. intro to FL; Alocasia 1 sp. intro to FL, TX, and HI; Arisaema 2 spp. native to the E USA from ND S to TX and all states E of that; Arum 2 spp. intro to WA, OR, CA, MO, IL, VA, and SC; Caladium 1 sp. intro to LA and FL; Calla 1 pan-north temperate sp. native to ND, MN, IA, WI, IL, IN, MI, OH, PA, MD, NJ, NY, CT, RI, MA, VT, NH, and ME; Colocasia 1 sp. intro to TX, LA, MS, AL, GA, FL, SC, NC, PA, and HI; Cryptocoryne 1 sp. intro to TX and FL; Dracunculus 1 sp. intro to OR, CA, and TN; Epipremnum 1 sp. intro to FL, HI, Virgin Is., and Puerto Rico; Peltandra 2 E NAM (+Cuba) spp. native to KS S to TX plus E USA from MN S to LA and all states east, including 1 endemic to SE USA, also intro in OR and CA;Philodendron 1 sp. intro to FL and HI; Pinellia 1 sp. intro to CA, OH, WV, MD, NJ, PA, NY, and CT; Pistia monospecific pantropical genus native to CA, AZ, CO, KA, TX, MO, LA, MS, GA, FL, SC, NC, OH, MD, DE, NY, NJ, and CT; Syngonium 1 sp. intro to FL; Xanthosoma 2 spp. intro to TX, FL, and HI; Zantedeschia 2 spp. intro to CA, OR, PA, and HI.
Lasioideae in the USA
Dracontium 1 sp. native to Peurto Rico.
Lemnoideae in the USA
Lemna 9 spp. native throughout the entire USA, including AK and HI; Spirodela 2 cosmopolitan spp. native throughout the entire continental USA and HI; Wolffia 7 cosmopolitan spp. native to most of the USA except NV, AZ, NM, and CO; Wolffiella 5 cosmopolitan spp. native to WA, CA, TX, OK, MO, AR, LA, IL, IN, OH, KY, TN, MS, AL, GA, FL, SC, NC, VA, PA, NJ, and MA.
Monsteroideae in the USA
Epipremnum 1 sp. intro to FL and HI.
Orontioideae in the USA
Lysichiton 1 sp. native to AK, WA, OR, CA, ID, MT, and WY; Orontium monospecific SE USA endemic sp. native from TX E to FL, N to KY, MA, and RI; Symplocarpus 1 E NAM endemic sp. native to MN, IA, WI, IL, IN, OH, KY, TN, NC, VA, WV, MI, PA, MD, DE, NJ, NY, CT, RI, MA, VT, NH, and ME.
Mexico AraceaeGenera
Aroideae in Mexico
Aglaonema 1 sp. intro to NL, Sin, Jal, Son, Ver, Gro, Chi, Tab, and Cam; Alocasia 5 spp. intro from Sin E to Coa and all S Mexico; Arisaema 5 spp. native and including 1 intro in Sin, NL, Nay, Tam, SLP, Jal, Col, Mic, Mex, Pue, Gro, Ver, Oax, and Chi; Arum 1 sp. intro to NL, Jal, and Mex; Dieffenbachia 2 spp. native from Sin to S NL and all through S Mexico; Dracunculus 1 sp. intro to Chi, Cam; Leucocasia 1 sp. intro to Jal and Pue; Peltandra 1 sp. intro Tlx; Philodendron ~44-46 spp. native and some intro throughout all of Mexico; Pinellia 1 sp. intro Mex; Pistia monospecific pantropical genus native throughout Mexico; Syngonium 9 spp. native to BCS, Sin E to NL, and all through S Mexico; Typhonium 1 sp. intro to Oax, Pue, Ver, Chi, and SLP; Xanthosoma 8 spp. native to most of Mexico except north-central and northeast; Zantedeschia 1 sp. intro to Mex.
Lasioideae in Mexico
Dracontium 1 sp. a narrow endemic of SW Chi.
Lemnoideae in Mexico
Lemna 7 spp. native throughout all of Mexico; Spirodela 1 sp. native throughout all of Mexico; Wolffia 2 cosmopolitan spp. native in Jal, Nay, Gto, Chi, Mex, Qro, Mor, and Cd Mex; Wolffiella 4 cosmopolitan spp. native to NE+C+SE Mexico.
Monsteroideae in Mexico
Monstera 13 spp. neoendemic genus native Sin E to NL and all through S Mexico, but primarily in the tropical south;Rhodospatha 1 sp. native to Ver and Chi; Spathiphyllum 5 spp. including 4 native and 1 intro to Nay E to Ver and all of S Mexico, including 1 endemic to SE Mexico.
Pothoideae in Mexico
Anthurium 31 spp. native (and 1 intro) from Sin to S NL and throughout S Mexico.
Zamioculcadoideae in Mexico
Zamioculcas 1 sp. intro QR.
Neotropical AraceaeGenera
Aroideae in the Neotropics
Adelonema 16 spp. neoendemic genus native to Costa Rica, Panama, Colombia, Peru, Bolivia, N Brazil, French Guiana, Guyana, and Suriname; Aglaonema 1 sp. intro to Cuba, Puerto Rico, Trinidad-Tobago, and Venezuelan Antilles; Alocasia 5 spp. intro to Cuba, Hispaniola, Jamaica, Puerto Rico, Leeward & Windward Is., Trinidad-Tobago, Venezuelan Antilles, NE Brazil, Venezuela, Paraguay, and Galapagos; Amorphophallus 1 sp. intro to Trinidad-Tobago; Arum 1 sp. intro to NE Argentina; Asterostigma 8 spp. W SAM endemic genus native to most of Brazil and NE Argentina; Bognera monospecific endemic to N Brazil; Caladium 19 spp. neoendemic genus native from Honduras S to Peru, NW Argentina, Brazil, Cuba, Hispaniola, Puerto Rico, the Leeward & Windward Is., the Venezuelan Antilles, and Trinidad-Tobago; Chlorospatha 70 spp. neoendemic genus native to Costa Rica, Panama, Colombia, and Ecuador; Colocasia 2 spp. introduced to Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is., Trinidad-Tobago, Venezuelan Antilles, Galapagos, Honduras, Nicaragua, Costa Rica, Colombia, Venezuela, Guyana, Brazil, Ecuador, Peru, Bolivia, and Paraguay; Dieffenbachia 60 spp. neoendemic genus native from S Mexico S through to Peru, Bolivia, NE Argentina (except Uruguay), and including all of the West Indies; Epipremnum 1 sp. intro to Bermuda, Honduras, Costa Rica, Colombia, Ecuador, Suriname, Trinidad-Tobago, Venezuelan Antilles, and Leeward and Windward Is.; Filarum monospecific endemic to Peru; Gearum monospecific endemic to N+C Brazil; Gorgonidium 8 spp. SAM endemic genus native to Peru, Bolivia, and N Argentina; Idimanthus monospecific narrow endemic to SE Brazil; Incarum 1 sp. W SAM endemic genus native to Ecuador, Peru, and Bolivia; Jasarum 1 sp. N SAM endemic genus native to Venezuela and Guyana; Lorenzia monospecific endemic to N Brazil; Mangonia 2 spp. E SAM endemic genus native to S Brazil and Uruguay; Montrichardia 2 spp. neoendemic genus native to Guatemala, Belize, Honduras, Nicaragua S to Peru, Bolivia, N+SE Brazil, Trinidad-Tobago, and the Leeward & Windward Is.; Peltandra 1 sp. E NAM genus native to Cuba; Philodendron ~600 spp. neoendemic genus native throughout CAM, the West Indies, and N SAM S to Bolivia, NE Argentina, and S Brazil (excluding Uruguay); Philonotion 3 spp. N SAM endemic genus native to Colombia, Venezuela, Guyana, French Guiana, Suriname, N Brazil, Peru, and Bolivia; Pistia monospecific pantropical genus native throughout CAM, the West Indies, and SAM S to Peru, Bolivia, and NE Argentina; Scaphispatha 2 spp. N SAM endemic genus native to most of Brazil and Bolivia; Spathantheum monospecific W. SAM endemic genus of Peru, Bolivia, and NW Argentina; Spathicarpa 3 spp. E SAM endemic genus native to Brazil, Bolivia, Paraguay, NE Argentina, and Uruguay; Synandrospadix monospecific endemic to Peru, Bolivia, Paraguay, and NW Argentina; Syngonium 41 spp. Mexico + neoendemic genus native from Mexico S to Peru, Bolivia, C+SE Brazil, Greater Antilles, Trinidad-Tobago, Venezuelan Antilles, and intro S Brazil, Bahamas, Netherland Antilles, Leeward & Windward Is.; Taccarum 6 spp. SAM endemic genus of Peru, Brazil, Paraguay, Bolivia, and NE Argentina; Typhonium 1 sp. intro to NE+S Brazil, Cuba, Trinidad-Tobago, and Windward Is.; Ulearum 2 spp. N SAM endemic genus of N Brazil, Ecuador, and Peru; Xanthosoma ~140 spp. native from Mexico S through to Peru, NW Argentina, Paraguay, S Brazil (exc. El Salvador), plus Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is., Trinidad-Tobago, and is intro to Galapagos, Jamaica, Venezuelan Antilles, and Cayman Is.; Zantedeschia 1 sp. intro to Nicaragua, Costa Rica, Colombia, Ecuador, NE Brazil, Dominican Republic, Puerto Rico, and Trinidad-Tobago; Zomicarpa 2 spp. narrow endemic genus of NE Brazil; Zomicarpella 2 spp. N SAM endemic genus of Colombia, N Brazil, and Peru.
Lasioideae in the Neotropics
Anaphyllopsis 3 spp. N SAM endemic spp. native to Venezuela, French Guiana, Suriname, and N Brazil; Dracontioides 2 spp. endemic to NE+SE Brazil; Dracontium 29 spp. neoendemic genus native to the Dominican Republic, Puerto Rico, Trinidad-Tobago, Windward Is., and from Nicaragua S to Peru, Bolivia, Paraguay, and C+SE Brazil; Urospatha 13 spp. neoendemic genus native to Guatemala, Honduras, Nicaragua S to Peru, Bolivia, Paraguay, and C+SE Brazil.
Lemnoideae in the Neotropics
Lemna 4 spp. native throughout the entire Neotropical zone S to C Chile, Argentina; Spirodela 3 spp. including 2 native and 1 intro throughout all of Neo zone except Guyana, French Guiana, Galapagos, and N Chile; Wolffia 5 cosmopolitan spp., including 3 native (includes 1 endemic to Colombia) and 2 intro found in Guatemala, El Salvador, Honduras, Greater & Lesser Antilles (except Venezuelan Antilles), Colombia, Ecuador, Venezuela, Suriname, Brazil, Bolivia, Paraguay, Uruguay, C Chile, and NE+NW Argentina; Wolffiella 5 cosmopolitan spp. native to Guatemala, El Salvador, Honduras, Costa Rica S to C Chile, N Argentina (exc N Chile), plus Greater Antilles, Leeward & Windward Is, and Trinidad-Tobago.
Monsteroideae in the Neotropics
Alloschemone 2 spp. N SAM endemic genus native to N Brazil and Bolivia; Epipremnum 1 sp. intro to Bermuda, Cuba, Hispaniola, Puerto Rico, Trinidad-Tobago, Leeward & Windward Is., Venezuelan Antilles, Colombia, Ecuador, Suriname, and E Brazil; Heteropsis 19 spp. neoendemic genus native from Nicaragua S to Peru, Bolivia, N Brazil, plus NE+S+SE Brazil; Monstera 73 spp. native from S Mexico S through to Peru, Bolivia, C+S Brazil, Leeward & Windward Is., Netherlands Antilles, and intro to Puerto Rico; Rhodospatha 45 spp. neoendemic genus native from S Mexico S through CAM (except El Salvador) and N SAM to Peru, Bolivia, N+SE Brazil, and Trinidad-Tobago; Spathiphyllum ~60 spp. native from S Mexico S through CAM and N SAM to Peru, N+C+SE Brazil, Trinidad-Tobago, and intro to Cuba, Puerto Rico, Dominican Republic, and Venezuelan Antilles; Stenospermation 58 spp. neoendemic genus native to Guatemala, Honduras, and Nicaragua S to Peru, Bolivia, N Brazil, plus disjunct in SE Brazil.
Pothoideae in the Neotropics
Anthurium 1459 spp. neoendemic genus native from Mexico all the way south through to Peru, Bolivia, and NE Argentina (except Uruguay) plus all throughout the West Indies (excluding the Bahamas).
Patagonia AraceaeGenera
Lemnoideae in Patagonia
Lemna 1 sp. native to SE Argentina; Spirodela 1 cosmopolitan sp. native to SE Argentina and C. Chile; Wolffiella 1 cosmopolitan sp. native to SE Argentina.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Willis, Lyrae (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, but also a lot comes from my own observations of North American species.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Flora of North America (FNA) (1993+). https://floranorthamerica.org/Main_Page.
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Neotropikey: Milliken, W., Klitgård, B., & Baracat, A. eds. (2009 onwards). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/ Retrieved Winter 2020 – present.
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
9 Sep, 2022
7 Sep, 2022
How to Identify the Araliaceae / Ginseng Family
Oplopanax horridus – Devil’s Club plant with flowers Page Last Updated August 28, 2026
Introduction to the Araliaceae Family
The Araliaceae family is best known for its most popular plant, ginseng. But there are so many other lovely plants in this family. My personal favorite member of this family is Oplopanax horridus, or Devil’s Club, like the one pictured above, which is native from southern Alaska, USA, throughout most of British Columbia, Canada, and south into Oregon, USA. Growing up in BC, it was a common site in mossy, wet forests and mountain ravines. It’s pretty typical of the family growing as a shrub with large leaves and small flowers in tall umbels followed by small red drupes.
The Araliaceae are part of the Apiales order and are very closely related to the Apiaceae (carrot) family, sharing many overlapping characteristics. In general, however, the Apiaceae are usually herbs that produce dry schizocarps, while the Araliaceae are usually shrubs or trees and produce berry-like drupes.
Beginner’s Guide to the Ginseng (Araliaceae) Family
If you’re new to plant morphology, this guide is a perfect beginner’s description to learn to identify the Araliaceae family, with no need to know any scientific jargon. Below this section are morphology photos to help you identify the family, followed by pictures of individual species found in North America. But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Description below the images for highly detailed scientific descriptions and genus-level distribution data across the American continents from Canada south to southern South America.
Leaves and Stems of the Gineseng Family
The Ginseng family is mostly perennial trees and shrubs, but there is an occasional woody vine and herb as well. None release milky juices when damaged. Most have medium to large leaves, including some over 3 m long, but occasionally they can be small (1-2 cm). Leaves are usually arranged in a spiral pattern around the stem and have sheaths that wrap around their base. Leaf blades are simple or compound (made of leaflets); when simple, the margins are often divided in some way, often lobed and maple leaf-like.
Flowers of the Ginseg Family
The flowers are usually small and arranged in umbels or spikes, which are often further arranged in large compound spikes or branching inflorescences, and they occasionally resemble the umbels of the Apiaceae family, which can cause confusion. The flowers are symmetrical with five petals that are often thick or fleshy with a highly variable calyx that may be reduced to a rim of teeth.
Reproductive Features of the Ginseng Family
The reproductive system varies in the ginseng family from bisexual flowers with both male (stamens) and female (ovary, style, and stigma) parts in the same flower to separate male and female flowers on separate plants (dioecious). But there are usually 5 stamens and up to 100 in some species. Flowers usually have a fleshy nectar-producing disk at the base of the styles (tubes that capture pollen).
Fruits of the Ginseng Family
The fruits in this family are almost always fleshy berry-like drupes (fleshy fruits with stony pits, like a cherry). But sometimes it is a dry fruit that splits into segments (schizocarp), similar to the Apiaceae (carrot) family.
Morphology of Araliaceae in North America
Some Araliaceae Species in North America
Aralioideae Subfamily
Aralianudicaulis – Wild Sarsaparilla
Herbaceous perennial with underground stems. Large compound leaves have 5 (3 – 7) finely serrated leaflets, which are often purplish green. Small white flowers in rounded clusters, 4 – 5 cm wide, on scapes not much taller than the leaves. Flowers are followed by edible purple-black berries. This plant is native to northern and eastern North America.
Araliaspinosa – Devil’s Walking Stick
An aromatic, spiny, deciduous shrub or small tree, 2 – 8 m tall, with exceptionally large, bipinnate leaves, 70 – 120 cm long. Small white flowers in compound panicles are followed by purplish-black berries. Native to eastern North America.
Fatsia japonica – Paperplant
Evergreen shrub with stout, sparsely branched stems. The large, 20 – 40 cm leaves are deeply palmately lobed with 7 – 9 lobes, spirally arranged, leathery, and borne on long petioles. Flowers are small, white, born in dense terminal compound umbels, followed by small black berries. Native to Japan and Korea, it is also cultivated in North America.
A highly invasive, vigorous, root-climbing vine with variably 3-5 lobed leaves, depending on the cultivar and whether it has reached reproductive age. It seldom flowers but produces small umbels of greenish-yellow flowers followed by purple-black berries. It spreads mostly vegetatively and takes over entire areas when it is left unchecked. Click for more information!
A woody, deciduous, spiny perennial shrub with large, spiny, palmately lobed leaves, small yellow-green flowers in racemes followed by clusters of small red berry-like drupes. This species is endemic to North America, primarily in the Pacific Northwest, with a small disjunct population in the Great Lakes. Click the link for more info!
Hydrocotyloideae Subfamily
Hydrocotyle ranunculoides – Floating Pennywort
Pennywort is a creeping, mat-forming aquatic perennial of shallow water or wet mud. It has thin stems and rounded to kidney-shaped leaves with ~3-7 shallow lobes on the margins and a deeply notched base, which makes it look almost peltate. Small flowers appear separately in clusters. It is native to North, Central, and South America but has become invasive elsewhere.
Uses of the Araliaceae
The Araliaceae are often used as ornamentals, including plants like the angelica tree (Araliaspinosa) and ivy (Hedera spp.), as well as houseplants such as Hedera, Aralia, Polyscias, Schefflera, and Fatsia. Please note that Hedera species have become a widespread invasive species in many areas and should only be grown with extreme caution.
Another use is the pith of Tetrapanax papyriferus, which is used to make Chinese rice paper. Other members are used medicinally, including ginseng roots from Panax quinquefolius and devil’s club (Oplopanax horridus) root bark, used for respiratory conditions.
Ecosystem and Wildlife Values of the Araliaceae
The Araliaceae is often a crucial late-season pollinator species in forested ecosystems that blooms in late summer, fall, and even early winter when other pollen sources have ended, providing essential energy reserves for overwintering wasps, native bees, hoverflies, and butterflies preparing for diapause or migration.
The large shrubs and vines create dense cover for nesting and habitat for birds, arboreal amphibians and reptiles, and insects.
Taxonomy of Araliaceae
There are 1450 species in 43 genera within the Apiales order of core Eudicots. Currently, there are two recognized subfamilies in the Araliaceae. The Hydrocotyloideae historically was considered part of the Apiaceae due to their herbaceous habit and schizocarps. However, modern phylogenetics showed that it was polyphyletic in the Apiaceae and was moved to the Araliaceae instead.
Furthermore, within the Araliaceae, there have been many generic changes since I last worked on the family, with some genera increasing massively (like Polyscias), others decreasing, and some appearing and some disappearing. Still, this is the most up-to-date information I have and will be making edits when new information becomes available.
Aralioideae Subfamily
The Aralioideae is by far the largest subfamily of the Araliaceae and is made mostly of woody shrubs and trees but is sometimes vines (root or stem climbers) or occasionally perennial herbs. Leaves are usually alternate and usually pinnately to palmately compound (rarely simple), stipulate with highly variable connate, intrapetiolar, hooded, or sometimes cauline stipules. Inflorescences are usually compound, often primary umbels, heads, or spikes arranged in racemes or panicles. The fruit is almost always a drupe.
The Hydrocotyloideae are mostly herbaceous perennials, rarely annuals, or aquatics, typically occurring in moist soils, wetlands, and shallow water. The stem is often prostrate, creeping, or mat-forming, rooting at the nodes, and creeping stems often have an endodermis. The leaf lamina is orbicular–peltate or deeply twice-lobed palmately; the margin is crenate or serrate, and they are stipulate, often small and attached at the petiole base. Flowers are small, and sepals are often tiny or absent. Fruits are laterally compressed schizocarps with a woody endocarp and no vittae (oil tubes) separating them from the Apiaceae.
Genera of the Hydrocotyloideae Subfamily
Hydrocotyle (182), Trachymene (59).
Key Differences From Similar Families
The Araliaceae are mostly confused with the closely related family, the Apiaceae, or carrot family. They can be difficult to differentiate, especially when the Araliaceae produces white umbels. However, some more common differences to look for include:
Apiaceae are usually herbs, while Araliaceae are usually shrubs and trees.
Araliaceae usually have stipules, even if very small or fused to the petiole base.
Apiaceae petiole bases lack spiules but almost universally sheathe the stem.
Apiaceae fruit is usually a dry schizocarp with two mericarps.
Araliaceae fruit is usually a berry-like drupe (but occasionally a schizocarp).
Scientific Botanical Description of the Araliaceae Family
Habit & Leaf Form of the Araliaceae
The Araliaceae are a morphologically diverse family of shrubs, moderate-sized trees (occasionally very large in some Polyscias), woody epiphytes, vines, and occasionally herbs (Panax, some Aralia, and the Hydrocotyloideae); occasionally some exhibit a switch-plant architecture with reduced foliage and photosynthetic shoots. They can be self-supporting, epiphytic, climbing, scandent, or rooted. Growth is predominantly pachycaul with large leaves and thick stems, but occasionally they are leptocaul in Pseudopanax, where long and short shoots are seen. They are resinous, lack colored latex, and may or may not contain essential oils.
Leaves are usually medium-sized but can be enormous (over 3 m in Aralia) or, more rarely, small, 1-2 cm long (e.g., Raukaua anomalus), and plants are sometimes conspicuously heterophyllous (e.g., Hedera helix). Their attachment to the stem is nearly always alternate, mostly spiral, or rarely distichous, four-ranked, opposite (Cheirodendron, Polyscias), or pseudowhorled (Panax). Leaves are often leathery, usually petiolate and rarely subsessile. They are usually more or less sheathing but may sometimes be non-sheathing; when sheathing, they have free margins. Leaves may be gland-dotted or non-glandular, aromatic or odorless.
Leaves are mostly simple or sometimes compound, including ternate, pinnate, palmate, multiply compound, and sometimes peltate (as in Hydrocotyloideae and some Harmsiopanax). When simple, margins vary from entire to palmately lobed or dissected, with pinnate or palmate venation. Leaves may or may not have stipules; when present, they are intrapetiolar but are often adnate to and can be difficult to distinguish from the petiole base. Some taxa have prickles or spines to defend the stems, petioles, and leaf midribs (as in Oplopanax).
Flowers of the Araliaceae
Plants exhibit diverse sexual systems and may be hermaphroditic, monoecious, andromonoecious, gynomonoecious, dioecious, or polygamomonoecious. Flowers are often arranged in compound inflorescences, with umbels or heads and rarely spikes as the primary structure, and are aggregated in large compound panicles or spikes. Inflorescences are terminal, axillary, leaf-opposed, or rarely epiphyllous.
Flowers are small, actinomorphic, cyclic, and usually 5-merous but rarely may be calyptrate. The floral receptacle has neither an androphore nor a gynophore. The perianth is usually arranged in 2 isomerous or anisomerous whorls or may be petaline when the calyx is reduced.
The calyx, when present, has 3–5 (–12) lobes or teeth in one whorl, free or connate. It is most often adnate to the inferior ovary and reduced to a short rim or to reduced teeth.
The corolla has 5 (3–20) distinct or basally connate petals in a single whorl, alternating with the calyx lobes. Petals are usually regular, often fleshy, and usually sessile, with broad bases inserted around the upper part of the ovary, and are rarely calyptrate. Estivation is predominantly valvate but may be imbricate in the Aralieae tribe.
Androecium of the Araliaceae
The androecium has 5 (3–12) or 100+ members, consisting exclusively of fertile stamens that are free from the perianth and from one another, all of equal size and strongly inflexed in the bud. Stamens are usually isomerous with the perianth and alternating with the petals (except when polyandrous).
Filaments are distinct, slender, and inserted on top or around the apigynous disk. Anthers are dorsifixed, versatile, introrse, and dehisce via longitudinal slits. Anthers are almost always tetrasporangiate (but occasionally appear bisporangiate by fusion during development) or multisporangiate in some Plerandra.
Gynoecium of the Araliaceae
The gynoecium is syncarpous to synovarious (rarely appearing pseudo-monomerous), with usually 2–5 (but 1–100) carpels and no false septa. In most cases, the ovary is inferior or semi-inferior or, rarely, superior in some Polyscias species (formerly Tetraplasandra).
A prominent nectariferous epigynous disk forms directly on the swollen style bases (stylopodium), crowning the tip of the ovary inside the stamen ring. The number of styles varies widely from 1 to 100, with one style for every carpel; they may be completely free, basally connate, or fused into a solid or hollow stylopodium column.
Stigmas are usually present and are terminal or decurrent, forming a double-stigmatic crest that caps the stylopodium. They may be wet or dry and are papillate.
Placentation is axile to apical in plurilocular ovaries (or parietal to apical in rare unilocular states). Each locule contains one functional pendulous ovule (or two, but the second is typically abortive) at maturity. They are epitropous, with a ventral raphe, and are anatropous, unitegmic, and crassinucellate or occasionally tenuinucellate.
Fruit of the Araliaceae
The Arialiaceae overwhelmingly produce fleshy, indehiscent drupes (most Aralioideae) with separable pyrenes or with one stone (there are as many pyrenes as locules).
However, most Hydrocotyloideae produce laterally compressed schizocarps with 2-5 (6-100) mericarps, featuring a woody endocarp and lacking oil tubes (separating them from the Apiaceae).
In some taxa, the gynoecia may fuse during maturation to form compact multiple fruits.
Seeds are pendulous, solitary, and possess well-developed, copious oily endosperm that is mostly entire but may be distinctly ruminate in some taxa (e.g., Hedera).
Global Distribution of Araliaceae
The Araliaceae are mostly a tropical family, but some are endemic to temperate climates as well. They are in Eurasia, Africa, Australia, New Zealand, New Caledonia, the Pacific Islands, and the Americas, from Arctic Canada to temperate South America.
Distribution of Araliaceae in the Americas
Canadian Araliaceae Genera
Aralioideae in Canada
Aralia 5 spp. native to all of Canada except NU; Eleutherococcus 1 sp. intro to ON; Hedera 1-2 spp. intro BC and ON, very invasive in coastal BC; Kalopanax 1 sp. intro to ON; Oplopanax 1 sp. native to BC, AB, YT, and ON; Panax 2 spp. native to ON, QC, NB, NS, and PE.
Hydrocotyloideae in Canada
Hydrocotyle 4 native to ON, QC, NB, NS, PE, and NL (excluding Labrador) and intro to BC.
USA AraliaceaeGenera
Aralioideae in the USA
Aralia 8 spp. are native and intro to all of the USA exccept NV; Cheirodendron 5 of 6 C Pacific endemic spp. endemic to HI; Eleutherococcus 1 sp. intro to UT, IN, KY, OH, WV, PA, NY, CT, and MA;Hedera 3 spp intro and invasive to most of the USA except NV, MT S to NM, ND S to OK, MN, IA, WI, VT, NH, ME, and inc. HI; Heptapleurum 1 sp. intro FL and HI; Kalopanax 1 sp. intro to NY, CT, MD, VA, OH, and IN; Oplopanax 1 sp. native to WA, OR, ID, WY, MI, NY, and AK; Panax 2 spp. native to all E USA from ND S to TX and all E except ND, TX, and FL; Polyscias 10 spp. including 9 spp. native/endemic to HI and 1 sp. intro in FL; Tetrapanax monospecific intro AL, FL, and HI.
Hydrocotyloideae in the USA
Hydrocotyle 9 spp. native and intro to most of the USA except ID, MT, WY, CO, ND, SD, NE, and IA, and it is intro in HI.
Mexico AraliaceaeGenera
Aralioideae in Mexico
Aralia ~5-9 spp. native throughout all of Mexico; Dendropanax ~3-6 spp. native to most of Mexico except BC, BCS, Son, and Sin; Didymopanax 1 sp. native to SW+SE Mexico, Ver; Oreopanax 13 spp. Mexico + neoendemic genus native throughout all of Mexico, including the Mexican Pacific Islands.
Hydrocotyloideae in Mexico
Hydrocotyle 5-10 spp. native throughout all of Mexico.
Neotropical AraliaceaeGenera
Aralioideae in the Neotropics
Aralia ~ 8 spp. native to CAM, Cuba, Hispaniola, Colombia, Venezuela, Peru, Bolivia, Paraguay, N Argentina, E+S Brazil; Crepinella 33 NW SAM endemic spp. of Colombia, Venezuela, Guyana, N+C Brazil, Ecuador, and Peru; Dendropanax ~75 spp. native to CAM, Greater Antilles, Leeward Is, Venezuelan Antilles, Trinidad-Tobago, tropical SAM S to Peru, Bolivia, NE Argentina (except for Suriname, French Guiana, and Uruguay); Didymopanax 38 Mexico & neoendemic spp. native to CAM, Cuba, Hispaniola, Puerto Rico, Leeward Is, Trinidad-Tobago, tropical SAM S to NE Argentina (exc NW Argentina, N Chile), including at least 12 narrow endemics of Brazil; Fatsia 1 sp. intro Juan Fernandez Is; Heptapleurum 1 sp. intro to Bermuda, Bahamas, Hispaniola, Jamaica, Puerto Rico, Leeward & Windward Is; Oreopanax 148 Mexico + neoendemic spp. of CAM, Antilles (exc Cayman Is, Aruba, Netherlands Antilles), Trinidad-Tobago, Colombia, Venezuela, Guyana, French Guiana, N+E+S Brazil, Ecuador, Peru, Bolivia, NW Argentina; Plerandra 1 sp. intro to Trinidad-Tobago; Polyscias 3 spp. intro to El Salvador, Bahamas, Hispaniola, Leeward Is., Puerto Rico, Trinidad-Tobago, and Venezuelan Antilles; Raukaua 1 sp. endemic to N+C Chile; Sciodaphyllum 146 neoendemic spp. of Jamaica, Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, Bolivia, and Venezuela; Tetrapanax monospecific intro to S Brazil.
Hydrocotyloideae in the Neotropics
Hydrocotyle 40-50 spp. native and widespread in moist habitats of CAM, Bermuda, the Bahamas, Cuba, Hispaniola, Jamaica, Puerto Rico, the Leeward & Windward Is., Galapagos, and all of SAM, with high diversity in the Andes.
Patagonia AraliaceaeGenera
Aralioideae in Patagonia
Raukaua 2 spp. endemic to N+C Chile (1) and S Argentina (1).
Hydrocotyloideae in Patagonia
Hydrocotyle 5 spp. native throughout Patagonia and the Falkland Islands.
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
FNA 1993+. Flora of North America. https://floranorthamerica.org/Main_Page. Accessed 2022-current.
iNaturalist.org 2020+. https://www.inaturalist.org/. Accessed 2020-current. If you like plants or nature in general, please join the iNaturalist community and start sharing your observations with others. The data we track is invaluable for scientists like me wanting to track population changes over time.
POWO 2019+. Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/. Accessed 2020-current.
USDA, NRCS. 2020+. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; Accessed 2020-present.
Watson, L., and Dallwitz, M.J. (1992). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.
Copyright Information
The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.
You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].
Welcome to my Plant Families of North America page! I have been absent awhile, but I am back, and this is my focus, teaching how to identify plant families. Over the next few weeks, I will be updating what I have so far. I will be adding new layman’s descriptions in addition to botanical descriptions, and I will be adding more morphology photos, including dissections of flowers where available. Please come back often and see what’s blooming!
A quick overview of basic taxonomy and how I have ordered this site. Plants are given a scientific name composed of two parts, the genus they belong to and the particular species they are. The genus can be thought of like plant cousins, whereas at the species level they are more like siblings. Beyond genus you get the family, which is all of the cousins from all the related families. Above that you get an order, which is like a group of similar families.
Below I have organized the families in their orders so that you can see similarities between related families. When you click on a particular family, you will get the characteristics and morphology pictures that represent that family, along with some of the species I have covered in North America from that family.
Note that most technical words have a hover-over description available, or go to the dictionary of botanical terms to learn more. In no time, you’ll be able to identify plants like a scientist!
Currently Seeking Funding To Continue This Non-Profit, Ad-Free Work
If you are able to donate so that I can continue this non-profit work of supplying people with scientific information on the plant families, native plants, and invasive species found throughout North America, please donate using the GoFundMe link below. Thank you! (COMING SOON)
5 Sep, 2022
5 Sep, 2022
How to Identify the Annonaceae or Custard Apple Family
Asimina triloba, American Pawpaw fruit, in flower Page Last Updated August 28, 2026
Introduction to the Annonaceae Family
The Annonaceae is an interesting family to learn to identify. They are mostly tropical trees and shrubs with unique flowers and fleshy, often edible and delicious fruits. The most well-known member of the Annonaceae in North America is the pawpaw fruit, or Asiminatriloba. It is the most northern member of this family and produces delicious fruits that taste similar to bananas. Learn how to identify the Annonaceae family with morphology photos like the flowers shown in the photo above of Asiminatriloba, which are typical for the Annonaceae family, with their 6 petals and 3 sepals and their androecium in a ball in the center.
The Annonaceae family is part of the Magnoliales order in the Magnoliids clade of angiosperms, the third largest clade after dicots (eudicots) and monocots. Occasionally this clade is referred to as a ‘peripheral angiosperm’ because it is neither a dicot nor a monocot, where the vast majority of flowering plants are classified. Instead, this clade is characterized by features of both dicots and monocots, including trimerous flowers (monocot) and branching veins (dicot), as well as pollen with one pore.
Beginner’s Guide to the Custard Apple (Annonaceae) Family
If you’re new to plant morphology, this guide is a perfect beginner’s description to learning to identify the Annonaceae family, with no need to know any scientific jargon. Below this section is additional information on uses and morphology photos to help you identify the family, followed by pictures of individual species found in North America. But for researchers or those wanting to learn a more in-depth version, refer to the Scientific Botanical Description below the images for highly detailed scientific descriptions and genus-level distribution data.
Leaves and Stems of the Custard Apple Family
The Annonaceae family is made of woody trees, shrubs, or vines that may be evergreen or deciduous. They are known for their fibrous and aromatic barks containing essential oils and resins.
Leaves are simple with smooth (entire) edges and are arranged alternately along the stem. The leaves do not wrap around or sheath the stem at their base. And while the leaves are generally odorless, some may be aromatic or dotted with tiny glands. Leaves never have tiny appendages at their base called stipules, which helps distinguish them from the Magnoliaceae.
Flowers of the Custard Apple Family
The flowers are arranged singly or in branched clusters. They are usually symmetrical, and their parts are usually found in multiples of three, similar to most monocots. However, they generally have a distinct outer layer of sepals and 2 inner layers of petals that are often thick and fleshy and sometimes contain visible nectar glands.
Reproductive Features of the Custard Apple Family
The male parts are very distinct, usually with many stamens that are packed together in a characteristic dense ball or flat-topped mass in the center of the flower, which is a good character to help identify the family. The ovary is superior, sitting above the point of where the petals attach.
Fruits of the Custard Apple Family
Fruits are usually fleshy aggregates of multiple berries that fuse together to form a larger, secondary fruit that is often edible. The seeds inside are sometimes encased in brightly colored fleshy coatings (aril or sarcotesta) that attract birds and animals.
Morphology of Annonaceae in North America
So far in North America, I have only photographed Asiminatriloba, since it is the most northern species of this primarily tropical family, but here are some pictures of different morphological aspects of that species.
Annonaceae Species I have Covered So Far in North America
So far in North America, I have only photographed Asiminatriloba, the morphology photos above show pictures of that species. When I cover more species, I will add more pictures here.
Asimina triloba—American Pawpaw
A large shrub or small tree growing to 11 m with simple, alternate-spirally arranged obovate–lanceolate leaves 25 – 30 cm long with a cuneate base, acute tip, and entire margin. Leaves smell similar to green bell peppers if bruised. Flowers are red-purple or maroon, 3 – 5 cm wide, and borne singly on stout, hairy axillary stalks (peduncles), appearing with or before the leaves in the spring. The fruit is a large yellowish to brown berry 5 – 15 cm long and weighing up to 510 g that is edible and sweet. Native to eastern North America. Click for more information on Asimina triloba
Uses of Annonaceae
Many have edible fruits, but non-commercial varieties should be eaten with caution, as they contain varying levels of annonacin, which has been implicated in neurodegenerative diseases. Still, several important tropical commercial fruits come from Annonaspecies (atemoya, cherimoya, custard apple, ilama, sugar apple, sweetsop, and soursop) and Artabotrys.
Medicinal uses include its use as an analgesic and astringent and to treat various conditions, including snakebite, diarrhea, dysentery, arthritis pain, rheumatism, convulsions, neuralgia, and weight loss.
Ecosystem and Wildlife Values of Annonaceae
The Annonaceae family provides critical, large, nutrient-rich aggregate fruits that serve as major food resources for tropical frugivores like primates, bats, toucans, tapirs, and peccaries, while in temperate zones, Asimina triloba fruits feed raccoons, foxes, opossums, and black bears.
Many species have fleshy flowers that smell of rotting meat, relying on beetles and small flies for pollination, who are rewarded with food or brood sites, while they also serve as host plants for many Lepidoptera, particularly swallowtail butterflies, that rely on the leaves for food.
In tropical forests, especially in Africa and the neotropics, Annonaceae species are critical parts of the forest structure, often dominating the understory.
Taxonomy of Annonaceae
The Annonaceae family has between 2,400 and 2,500 species in 107-110 genera, depending on the classification. They are part of the Magnoliales order in the Magnoliids clade, which is an early-diverging lineage of mesangiosperms, not a true dicot or monocot.
The family is divided into 4 subfamilies as follows:
Anaxagoreoideae Subfamily
The Anaxagoreoideae is a group of 25 species in a single genus found in tropical America and the tropics in Southeast Asia. They have 2-ranked trunk leaves, sessile stigmas, and dry follicles that are explosively dehiscent, which is a key diagnostic feature.
Genera of the Anaxagoreoideae Subfamily
Anaxagorea (25).
Ambavioideae Subfamily
The Ambavioideae is a more widespread group found throughout the tropics and subtropics. This subfamily is characterized by a truncate and dilated anther connective, an intine that does not extrude through the aperture, and ovules with a middle integument.
The Annonoideae is a widespread but mostly tropical subfamily, but it does extend into temperate eastern North America. It is characterized by trimerous whorls, often highly modified stamens, and specialized aggregate fruits.
The Malmeoideae is restricted to the lowland tropics and is characterized by pollen with a single aperture and specific molecular markers, as well as often having a glass-like endosperm with spiniform ruminations.
Because the Annonaceae share primitive morphological traits with other orders in the Magnoliid clade (such as alternate, entire leaves, aromatic tissues, trimerous flowers, and multiple stamens), field identification can sometimes be tricky.
Myristicaceae members can look similar, but they are easily distinguished by their clear to blood-red latex, which is visible when the bark is slashed. Plants are also dioecious with small, apetalous flowers compared to usually bisexual Annonaceae flowers with distinct sepals and petals.
Magnoliaceae can be differentiated by their large deciduous stipules that leave a distinct ring-like scar surrounding each node, while the Annonaceae have no stipules at all. Magnoliaceae also produce aggregates of follicles or samaras with seeds hanging via funicles, while Annonaceae form berries or syncarps.
The Lauraceae family also shares simple, aromatic leaves and woody habits, but the Lauraceae anthers open via characteristic upward-curving valves or flaps, whereas Annonaceae anthers open via longitudinal slits. The Lauraceae also produce flowers with a single carpel that produces single-seeded drupes, often accompanied by a receptacle or cupule, rather than aggregate berries or syncarps.
Scientific Botanical Description of the Annonaceae
Habit & Leaf Form of the Annonaceae
The Annonaceae are always trees, shrubs, or lianas that are deciduous or evergreen and produce essential oils and may be resinous. The inner bark is typically fibrous and aromatic, and the pith is septate to diaphragmed. Plants may be self-supporting or climbing via scrambling or hooked, woody pedicels.
Leaves are typically arranged alternately in a spiral and are non-sheathing, simple, and petiolate and may or may not be gland-dotted or aromatic. The lamina and its margins are entire, and the lamina is always pinnately veined and cross-venulate. Leaves have no stipules. Domatia occurs in 10+ genera as pockets or occasionally as hair tufts.
Flowers of the Annonaceae
Annonaceae plants are usually hermaphrodite or sometimes dioecious and rarely monoecious. They are often axillary but may be terminal, leaf-opposed, or cauliflorous. They are typically in monochasial cymes but may be reduced to a solitary flower or in fasciculate clusters.
The receptacle may be elevated, enlarged, or flat. Flowers are regular and cyclic or partially acyclic. Free hypanthium is absent, and a hypogynous disk is present.
The flowers are strictly 3-merous, arranged in 3 distinct whorls, with 3 parts in each whorl (9 parts, rarely more). The perianth has a distinct calyx and corolla that may be petaline; however, sometimes it can be difficult to determine when the outer 1-2 whorls are sepaloid.
The calyx has 3 parts, typically free (sometimes basally connate), and the lobes are longer than the tube but smaller and thinner than the petals.
The corolla typically has 6 free parts (sometimes basally connate) in 2 distinct whorls. Petals are usually thick, fleshy, or coriaceous, with valvate or imbricate aestivation. Inner petals may be smaller, clawed, or connivent over the reproductive organs and frequently bear nectar-secreting glands at their bases. Rarely is the inner petal whorl missing.
Androecium of the Annonaceae
The androecium contains 6–100+ members that mature centripetally. Members are usually fertile stamens, but sterile staminodes occur in several lineages and are usually located outside or inside the fertile stamens; staminodes are non-petaloid and are often reduced, glandular, or shield-like.
Stamens are free of the perianth and each other, are all equal, and are usually densely packed and spirally arranged in multiple whorls on the receptacle, often forming a compact protective ball or flat-topped shield around the gynoecium.
Filaments are characteristically short, stout, and thick. Anthers are adnate, non-versatile, linear to oblong, tetrasporangiate, and extrorse and dehisce via longitudinal slits away from the gynoecium.
Gynoecium of the Annonaceae
The gynoecium is superior and contains 1 (rare) to 100+ carpels. It is usually apocarpous (carpels spiraled or cyclic) or synstylovarious to syncarpous (e.g., Monodora).
The carpel contains one to many ovules. Placentation in apocarpous taxa of individual carpels is ventral or basal when reduced to a single ovule; free carpels are basal. When syncarpous, placentation is parietal.
Stigmas are of the wet type and papillate, secreting a sticky, mucilaginous exudate. In many apocarpous species, individual stigmas coalesce into an aggregate head.
Ovules are anatropous, bitegmic, and crassinucellate. They are ascending with a ventral raphe and may be arillate at the base, developing a distinct sarcotesta or aril.
Fruit of the Annonaceae
The fruit of the Annonaceae is a fleshy aggregate that is often made of berries; sometimes fruiting carpels coalesce into a secondary syncarp. The fruiting carpel is indehiscent or pseudo-dehiscent.
Seeds are endospermic with 1 to many per pistil and may be encased in fleshy white, yellow, orange, or red arils or sarcotesta, which attract frugivorous birds and animals. The endosperm is ruminate, oily, and has amyloid.
Global Distribution of Annonaceae
The Annonaceae are primarily a subtropical and tropical family, especially common in lowland forests, and are very rarely temperate. It is widespread, especially in the Old World. In the Americas, it is found all over the Neotropics and north as far as southern Canada.
Distribution of Annonaceae in the Americas
Canada AnnonaceaeGenera
Annonoideae Subfamily in Canada
Asimina 1 E NAM endemic spp. native to southern ON, the northernmost Annonaceae in the world.
USA AnnonaceaeGenera
Annonoideae Subfamily in the USA
Annona 3 spp. native to FL; Artabotrys 1 sp. introduced in HI; Asimina 11 E NAM endemic spp. native to the E USA from ND S to TX and all states E excluding ND, SD, MN, CT, RI, VT, NH, and ME; Deeringothamnus monospecific endemic of FL; Polyalthia 1 sp. intro to FL.
Mexico AnnonaceaeGenera
Anaxagoreoideae Subfamily in Mexico
Anaxagorea 1 sp. native to SW Mexico, Ver.
Ambavioideae Subfamily in Mexico
Cananga 1 sp. intro to SW Mexico, Ver.
Annonoideae Subfamily in Mexico
Annona 14 spp., including 12 native all through Mexico and 1 sp. introduced to Sin, east to Tam, and south to Oax, Chp, QR, and Yuc;Cymbopetalum 2 spp. native to Chp, Ver, and Oax; Guatteria 2 spp. are native to SW+SE+S Mexico, Ver; Xylopia 1 sp. native to S Chi.
Malmeoideae Subfamily in Mexico
Desmopsis 20 spp. inc. 19 endemic to rainforests of SW+SE Mexico and Ver; Mosannona 1 sp. native to Cam, Chp, QR, Ver, Yuc; Oxandra 4 spp. native to SW+C+SE Mexico and Ver, including 1 narrow endemic of Chp; Sapranthus 3 ~neoendemic spp. native Gro, Oax, QR, Sin, Chp, and Ver, including 1 narrow endemic of Chp; Tridimeris 10 Mexican endemic spp. native to E+C Mexico including 1 narrow endemic of Chp; Unonopsis 2 neoendemic spp. native to SW+SE Mexico, including 1 endemic to Oax; Uvaria 1 of 168 Old World Tropics spp. intro Jal.
Neotropical AnnonaceaeGenera
Anaxagoreoideae Subfamily in the Neotropics
Anaxagorea ~22 spp. native to CAM (exc. El Salvador), Trinidad-Tobago, tropical SAM S to Peru, Bolivia, and C+SE Brazil, including 5 narrow endemics of Costa Rica & Panama, S Venezuela (2), N Peru, and SE Brazil.
Ambavioideae Subfamily in the Neotropics
Cananga 1 sp. intro Guatemala, Nicaragua, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is., and Trinidad-Tobago; Tetrameranthus 8 N SAM endemic spp. of N Brazil, Colombia, Venezuela, French Guiana, Ecuador, and Peru.
Annonoideae Subfamily in the Neotropics
Annona ~160 spp., mostly endemics also widely cultivated throughout CAM, Bahamas, Antilles, SW Caribbean, tropical SAM S to N Argentina (excluding Chile); Artabotrys 1 sp. intro to Bahamas, Leeward Is., Windward Is, and Trinidad-Tobago; Bocagea 4 spp. endemic to E Brazil; Cardiopetalum 3 N SAM endemic spp. of Suriname, French Guiana, N+C+E Brazil, Peru, and Bolivia; Cymbopetalum 27 Mexico + Neoendemic spp. native from S Mexico S through CAM and tropical SAM S to Peru, Bolivia, C+E Brazil; Desmos 1 sp. intro to C+E Brazil and Trinidad-Tobago; Diclinanona 3 N SAM endemic spp. native N+C Brazil, Colombia, Peru, and Venezuela;Duckeanthus monospecific narrow endemic of N Brazil; Duguetia 91 spp. native from Nicaragua S through tropical SAM S to Peru, Bolivia, Paraguay, S Brazil (+4 spp. endemic to W Africa);Ephedranthus 7 SAM endemic spp. native to tropical SAM S to Peru, Bolivia, Paraguay, SE Brazil (exc. Ecuador); Froesiodendron 3 N SAM endemic spp. native to Colombia, Peru, and N Brazil; Fusaea 2 N SAM endemic spp. native to N+NE+C Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Venezuela, and Bolivia; Guatteria 186 neoendemic spp. native from S Mexico S through CAM (excluding El Salvador), Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, tropical SAM S to Peru, Bolivia, C+S Brazil; Hornschuchia 12 narrow endemic spp. of E. Brazil; Monodora 1 sp. intro Trinidad-Tobago; Porcelia 7 neoendemic spp. of Costa Rica, Panama, Colombia, Venezuela, N+E+S Brazil, Ecuador, Peru, and Bolivia; Trigynaea 9 N SAM endemic spp. native to Colombia, Venezuela, Guyana, Suriname, N+E Brazil, Ecuador, Peru, and Bolivia; Uvaria 1 sp. intro to Trinidad-Tobago; Xylopia 40 spp. native to CAM, Cuba, Jamaica, Trinidad-Tobago, tropical SAM S to Peru, Bolivia, NE Argentina.
Malmeoideae Subfamily in the Neotropics
Bocageopsis 4 SAM endemic spp. native to Colombia, Venezuela, Guyana, Suriname, French Guiana, N+C+S Brazil, Peru, and Bolivia; Cremastosperma 34 neoendemic spp. native to Costa Rica, Panama, Colombia, Venezuela, N+C Brazil, Ecuador, Peru, and Bolivia, with most diversity in the narrow tropical zone W of the Andes; Desmopsis 27 spp. native from S Mexico S through all of CAM to Colombia, including narrow endemics in Cuba (1), Costa Rica (4), Colombia (3), Honduras (3), and Panama (3). Klarobelia 14 neoendemic spp. native from Costa Rica S to Colombia, Venezuela, N Brazil, Ecuador, Peru, Bolivia, including several endemics to Ecuador; Malmea 7 neoendemic spp. native to Panama, Colombia, Guyana, Suriname, N+NE Brazil, and Peru; Monoön 1 sp. intro Trinidad-Tobago; Mosannona 14 Mexico + neoendemic spp. native to Guatemala, Belize, Honduras, Costa Rica, Panama, Colombia, N Brazil, Guyana, Suriname, Ecuador, Peru, and Bolivia, including 6 narrow endemics of Costa Rica, Barro Colorado Is. Panama, Guatemala, Suriname and Guyana, and Ecuador; Onychopetalum 2 SAM endemic spp. of Venezuela, N+C Brazil, Peru, and Bolivia; Oxandra 28 Mexico + neoendemic spp. native from S Mexico, Guatemala, Belize, Nicaragua, Costa Rica, Panama, Greater Antilles (excluding Cayman Is), Leeward + Windward Is, SW Caribbean, tropical SAM S to Peru, Bolivia, C+SE Brazil, including 9 narrow endemics of Colombia (3), Suriname, Guyana, Brazil (4); Polyalthia 1 sp. intro to Trinidad-Tobago; Pseudephedranthus 2 N SAM endemic spp. of Venezuela, Guyana, Suriname, and N Brazil; Pseudomalmea 4 N SAM endemic spp. of Colombia, Venezuela, N Brazil, Ecuador, Peru, and Bolivia; Pseudoxandra 24 tropical SAM endemic spp. native to Colombia, Venezuela, Guyana, French Guiana, N+C Brazil, Peru, and Bolivia; Ruizodendron monospecific neoendemic of Colombia, N Brazil, Ecuador, Peru, Bolivia, and disjunct Honduras; Sapranthus 9 Mexico + N neoendemic spp. native to CAM and Colombia, including 1 narrow endemic of Cesar, Colombia. Unonopsis 47 neoendemic spp. are native from S Mexico, CAM (excluding El Salvador), and tropical SAM S to Peru, Bolivia, and C+S Brazil.
Patagonia AnnonaceaeGenera
Absent
Additional Information and References
Visit Lyrae’s Dictionary of Botanical Terms to learn the terminology of botanists. Note that if you hover over most of the words in the articles, you can also get definitions from them there.
Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
Cruz-Chacon, Ivan de la Marisol Castro-Moreno, Lorena Mercedes Luna-Cazares, and Alma Rosa Gonzalez-Esquinca (2016). La Familia Annonaceae Juss. en México. Lacandonia, year 10, vol. 10, num. 2: 71-82, December 2016.
Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
Neotropikey: Milliken, W., Klitgård, B. & Baracat, A. eds. (2009+). Neotropikey: Interactive key and information resources for flowering plants of the Neotropics. www.kew.org/neotropikey.com (accessed 2020 – current).
POWO (2019). Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet: http://www.plantsoftheworldonline.org/ Retrieved Winter 2020-current.
USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout the fall of 2020.
Currently Seeking Funding To Continue This Non-Profit, Ad-Free Work
If you are able to donate so that I can continue this non-profit work of supplying people with scientific information on the plant families, native plants, and invasive species found throughout North America, please donate using the GoFundMe link below. Thank you!
5 Sep, 2022
25 Aug, 2022
Cypripedium acaule Pink Lady's Slipper Orchid
Cypripedium acaule the Pink Lady Slipper or Moccasin Flower – photo from Allatoona Creek, Georgia by Lyrae Willis
Pink Lady Slipper or Moccasin Flower Cypripedium acaule
Introduction
These gorgeous orchids are always a lovely treat when you find them growing in the forest. Fortunately, they are not excessively rare, though they are not all that common either. Cypripedium acaule is part of the Cypripedioideae subfamily in the Orchidaceae family. It goes by two common names the Pink Lady Slipper Orchid or the Moccasin Flower after their slipper or moccasin-shaped flowers that are unique to their genus. Orchids everywhere are declining in population due to habitat loss, climate change, and highly specific pollination with poor overall pollination rates. If you do find these please never pick the beautiful flowers. Instead, leave them there to hopefully be pollinated and produce the next generation. Take out your phone and take pictures of the beautiful flowers instead. You can put them on your computer desktop or print them and frame them for your wall and enjoy them for many years.
Description of Cypripedium acaule
Stem & Leaves
Pink Lady Slippers are erect herbaceous perennials 15 – 60 cm tall with solitary flowers on a leafless peduncle (flower stalk).
Two leaves grow opposite from each other directly from the rhizome. They are ovate or broadly elliptic to oblong in shape and measure 9 – 30 cm long and 2.5 – 15 cm wide. Rarely plants will only have one leaf.
Young leaves of Cypripedium acaule; photo from Allatoona Creek, Georgia, USA
Flower closeup of Cypripedium acaule showing the vertical slit in the pouch; Allatoona Creek, GA, USA
Flowers & Fruits
The showy solitary flowers bloom from April to July. They have tepals (sepals and petals) that are yellowish-brown, reddish-brown, pinkish, or even green. They are deflexed or spreading and may be slightly twisted, and are 1.9 – 5.2 cm long. The lip (labellum) is located below the tepals and is shaped like a large pouch with a slit down the middle, slipper or moccasin-like. It is usually a light pink but occasionally may be magenta and is obovoid in shape, 3 – 6.7 cm long.
Toxicity
The Cypripedium genus all have glandular hairs on the leaves and stems. The compound in the hairs can cause contact dermatitis similar to poison ivy.
Similar Species Frequently Confused With
It is difficult to confuse Cypripedium acaule for most other genera due to the unique moccasin-like lip on the flower. Sometimes people do mistake flowers of other genera, but if you just look for the distinctive labellum or lip that is shaped like a pouch with a slit down the middle, you can tell for certain it is a Cypripedium. So, most misidentifications are with other members of the same genus. Other Cypripedium species can be differentiated as follows:
Cypripedium reginae Showy Lady Slipper has a more limited range from Saskatchewan east to Newfoundland Island in Canada and the northern US from Minnesota south to Arkansas and east to Maine, but mostly concentrated in the states that border Canada. It is taller, growing to 100 cm, and usually sprouts many stems from the same rhizome. Showy Lady Slipper has more leaves, with 3 – 5 leaves per stem. It also has larger and much more showy white tepals and usually a brighter pink or magenta lip.
Cypripedium parviflorum Yellow Lady Slipper is another largely eastern North American species that extends to the Canadian Rockies and Arctic in the west and the Rocky Mountains in the US states. Otherwise, it has a very similar eastern range as Cypripedium reginae. It is fairly easy to tell apart, however, since its lip is always yellow.
Cypripedium candidum Small White Lady Slipper has a limited range and is listed as a Vulnerable species globally. It is rare and endangered in Canada but can be found in the extreme southern parts of eastern Canada from Saskatchewan east to Ontario. In the US, it is also rare and vulnerable and can be found from North Dakota south to Nebraska and east to New York, with some also found from Missouri south to Alabama. It is a much smaller plant, only up to 36 cm tall, and has a smaller lip that is always white.
Cypripedium montanum Mountain Lady Slipper is another rare vulnerable orchid that is found in the Pacific Northwest from Alaska south to northern California and east to the Alberta Rocky Mountains in Canada and Montana in the US. It is typically found only at high elevations in open forests and subalpine slopes. It grows to 70 cm tall and has 1 – 3 large flowers on top of its stem, and its pouch is always white.
Distribution of Cypripedium acaule
Moccasin Flower is a central and eastern Canadian and eastern USA species. It is not found anywhere else in the world.
In Canada, Cypripedium acaule is found in Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island, and Newfoundland Island (not Labrador). It may also be present in the Northwest Territories.
In the USA, Pink Lady Slipper is found in Minnesota, Wisconsin, Illinois, Michigan, Indiana, Michigan, Indiana, Ohio, Kentucky, Tennessee, Alabama, Georgia, North & South Carolina, Virginia, West Virginia, Pennsylvania, Delaware, Maryland, Washington DC, New York, New Jersey, Connecticut, Rhode Island, Massachusetts, Vermont, New Hampshire, and Maine.
Habitat & Growing Conditions of Cypripedium acaule
Cypripedium acaule tolerates a wide range of shade and moisture conditions being found in dry to wet forests, shrublands, and slopes, but it prefers partial shade and well-drained slopes. However, it requires highly acidic soils, which is probably why it is often found in pine forests but can be seen in deciduous and mixed woods as well. It is generally found below 1200 m in elevation.
Growing Pink Lady Slipper in Your Garden
Cypripedium acaule is challenging but not impossible to grow yourself if you don’t already have a highly acidic or coniferous forest to plant them in. For a long time, it was believed that it could not be cultivated due to a belief that a fungal association found in the forest was required for germination and growth. However, Pink Lady Slipper is available commercially but is not easy to find as it is more difficult to grow than other species. You will not be able to grow it from seed as special conditions and fungal associations are still required for germination, but once it has true leaves, it can be moved into a garden.
To grow commercially purchased plants of Cypripediumacaule, the only real critical factor is soil pH. It absolutely must be kept below 5.0 to prevent the plants from rotting from the activity of soil microbes that increase above pH 5.0. Anywhere from 4.0 – 4.5 pH is ideal for Pink Lady Slipper. To keep the pH so low, you must grow them in a container so that you can better control the conditions. Use a significant amount of peat moss or pine duff in the soil and use pH-neutral perlite to improve drainage. Tap water should never be used to water them due to the risk of Calcium in the water that would raise the pH. Instead, use rainwater or distilled water mixed with 2 oz of vinegar per gallon.
Other things to consider are where to place the pots. Ideally, morning sun or dappled sunlight under a tree is best. And be sure to sink the pots into the ground in winter or store them in a cold frame.
Wildlife Values of Cypripedium acaule
Native bees routinely visit the flowers.
Status of Cypripedium acaule
Pink Lady Slipper is currently listed as Least Concern on the IUCN Red List. However, as with most woodland plants, the population of mature individuals being found is decreasing.
In Canada, Pink Lady Slipper is considered Locally Secure S5 in Ontario, Quebec, New Brunswick, Nova Scotia, and Prince Edward Island. It is Apparently Secure S4 in Saskatchewan and Newfoundland Island. In Alberta and Manitoba, it is Vulnerable S3.
In the USA, Cypripedium acaule is considered Locally Secure S5 in West Virginia, Virginia, and North Carolina. It is considered Apparently Secure S4 in Kentucky, Tennessee, New York, New Jersey, Delaware, Connecticut, and Georgia. In Alabama, it is considered Vulnerable S3. It is considered Critically Imperiled S1 in Illinois and Indiana. In all other states where it is found, its status is not yet determined.
Traditional or Other Uses of Pink Lady Slipper
Cypripedium acaule Medicinal Uses
Pink Lady Slipper roots were used by the Algonquin for stomachaches, menstrual disorders, kidney and urinary infections, and venereal diseases. Cherokee used the root as an analgesic, anticonvulsive, to treat colds, flu, stomachaches, kidney problems, worms, and ‘female trouble’. Iroquois used them in a decoction as an analgesic and in a poultice for bite wounds. Menominee used it to treat urinary problems and ‘male disorders’. Micmac and Penobscot used the root as a sedative for nervousness. Rappahannock used the dried roots in whiskey as a panacea for general ailments.
Pink Lady Slipper as an Ornamental
Due to the challenges of growing it this plant is only occasionally grown as an ornamental. But for the most serious and dedicated gardeners or orchid lovers, it is a lovely addition to any woodland garden.
Ethical Wildcrafting of Cypripedium acaule
Check the status in your state before harvesting since it is vulnerable in some areas. See the above section on Status. Alternatively, grow it in your garden but do not attempt to harvest wild plants to transplant to your garden as, most likely, you will simply be killing the plant. Instead, buy commercially available plants that have been germinated in an orchid lab.
Generally speaking, I do not recommend wildcrafting this plant in any form. Transplanting has a poor survival rate, and the only other reason for harvesting is the root to be used medicinally. If using this root is part of your traditional heritage, and you want to harvest some, always use the 1 in 20 rule of Ethical Wildcrafting. Harvest the roots of only one in every plant you see in an area where they are locally common.
Wildcrafting and Processing
Use a digging stick to loosen the roots from the soil. Picked roots can be placed in a basket, bowl, or paper bag and brought home for processing. If you are harvesting multiple products on the same day, be sure to label the roots in a paper bag so that you do not confuse different plants.
Roots should be brushed clean of any dirt and then chopped into more manageable pieces before drying. Dried roots are notoriously difficult to cut into smaller pieces once dried.
Once dried, the roots can be stored in a jar for later use. Label your jar with the species name and the date, and I also usually add the location of the harvest for my own reference. Do not grind or crush the leaves or roots until you are ready to use them. This will keep them as fresh as possible to preserve their medicinal properties. When you pre-grind, even if stored in glass jars, this increases the oxidation rate and rapidly degrades the medicinal properties reducing their useful shelf-life.
