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29 Mar, 2023

How to Identify the Apiaceae / Carrot Family

Daucus carota inflorescences are very typical for the Apiaceae family
Daucus carota inflorescences are very typical for the Apiaceae family

Table of contents

Introduction to the Apiaceae Family

The Apiaceae family is widespread globally but is particularly common in north 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 schizocarps, while the Araliaceae are usually shrubs or trees and usually produce berry-like drupes.  

Flowers of the Apiaceae

Plants are usually hermaphrodite but may also be andromonoecious, polygamomonoecious, or dioecious (Acronema). Pollination is entomophilous.  Numerous small flowers are almost always in a characteristic flat-topped terminal cymose umbel(s). Otherwise, inflorescences are sometimes in cymose heads or rarely reduced to a single flower. Inflorescences may be pseudanthial and often associated with sterile flowers at the periphery and may or may not have involucral bracts. Flowers are usually actinomorphic but may be zygomorphic at the umbel edge. The petals are unequal in size, with those pointing outwards from the umbel larger than those pointing in. Flowers are usually fairly small, possess bracts, and may be regular to slightly irregular in the corolla.  Flowers are usually perfectly 5-merous (except for the gynoecium) and are tetracyclic. Free hypanthium is not present. The perianth usually has a distinct calyx and corolla (but the calyx is often very reduced). The perianth may be sepaline (corolla rarely absent) or petaline (calyx teeth sometimes absent) with 4–10 parts in two (or one) isomerous whorls. The calyx, when detectable, has five parts in one whorl that may be free or connate (often reduced to a rim but never forming a tube). Sepals are persistent and may be lobulate, blunt-lobed, or toothed. The corolla also has five parts in one whorl. The white, yellow, pink, or purple petals are always free, valvate, and may be unequal or regular. 

Androecium of the Apiaceae

The androecium has five members (all stamens) that are free of the perianth and each other. They are all equal to unequal and are found in 1 whorl. Their five stamens are all fertile, isomerous with the perianth, oppositisepalous, and inflexed in bud. Anthers are dorsifixed or basifixed, introrse, tetrasporangiate, and dehisce via longitudinal slits.

Gynoecium of the Apiaceae

The gynoecium is 2 carpelled, and the pistil is one or two-celled. The gynoecium is synovarious, median, and inferior. The ovary is 2(1) locular. An epigynous disk is present. Two apical styles are free to partly joined, with their bases thickened into one or two stylopodia that crown the ovary. Stigmas are wet type, non-papillate, and Group IV type. Placentation is either axile or apical. There are 1 or 2 ovules per locule (usually 2 with 1 abortive) that are pendulous and either epitropous or anatropous. Ovules have ventral raphe, are non-arillate, unitegmic, and are tenuinucellate or pseudocrassinucellate.  

Fruit of the Apiaceae

The fruits of the Apiaceae are non-fleshy dry schizocarps with 2 mericarps that are united facially. The mericarps are 1-seeded in each part, with the integument sometimes united with the pericarp. Seeds are oily and endospermic.

Habit & Leaf Form of the Apiaceae

Plants 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. Stems are hollow between leaf joints and are often ribbed (Angelica, Celery).  Sometimes they are switch-plants, occasionally with the principal photosynthesizing function transferred to stems (e.g., Platysace compressa) or phyllodineous (petiole or rachis performs leaf function) (e.g., Lilaeopsis). Leaves are usually well-developed but can be reduced in switch forms. Plants are usually non-succulent but occasionally can be succulent (e.g., Crithmum) and may or may not have a basal aggregation of leaves. They can be helophytic, mesophytic, or xerophytic (e.g. Eryngium). Plants may be conspicuously heterophyllous (e.g., Apium inundatum) or not. Leaves are small to large and arranged alternate or alternate and opposite (usually just opposite on upper leaves). Leaves are usually herbaceous but may occasionally be leathery or rarely fleshy. Their attachment to the stem is either petiolate or sometimes perfoliate or peltate, more or less sheathing with sheaths that have free margins and may or may not be pulvinate. Leaves may or may not be gland-dotted and are usually fetid, and only rarely are they odorless. Leaf arrangement may be simple or compound ternate, imparipinnate, bipinnate, multiply compound, or rarely palmate.  Lamina, when simple, is usually dissected pinnatifid (usually), palmatifid (in Sanicula, Astrantia, Eryngium), or spinose (Eryngium), but sometimes may be entire.  They are pinnately, palmately, or parallel-veined. Leaves are usually exstipulate (but sometimes with stipular flanges) or sometimes stipulate (Hydrocotyloideae).

Uses of Apiaceae 

Many 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, etc but note that many ornamentals have been modified and have enlarged bracts or sepals and are not representative of the family.  Many have useful medicinal purposes to treat a wide variety of ailments, yet others have notoriously poisonous resins or alkaloids such as Cicuta, Conium (hemlocks), Aethusa (fool’s parsley), and others are phototoxic (Heracleum mantegazzianum). 

Morphology of Apiaceae in North America

Inflorescence of Conium maculatum - a flat-topped umbel very typical of the Apiaceae family
Inflorescence of Conium maculatum – a flat-topped umbel very typical of the Apiaceae family
Bipinnate leaves of Chaerophyllum procumbens - a common leaf arrangement seen in Apiaceae
Bipinnate leaves of Chaerophyllum procumbens – a common leaf arrangement seen in Apiaceae
Herbaceous growth habit of Heracleum maximum - typical of Apiaceae species, though the palmate leaves are much less commonly seen.
Herbaceous growth habit of Heracleum maximum – typical of Apiaceae species, though the palmate leaves are much less commonly seen.
Herbaceous stem of Heracleum mantegazzianum - most Apiaceae members are herbaceous perennials or annuals.
Herbaceous stem of Heracleum mantegazzianum – most Apiaceae members are herbaceous perennials or annuals.
Flowers of Heracleum maximum in compound umbels. Small white flowers that become zygomorphic at the umbel edge are common among the Apiaceae.
Flowers of Heracleum maximum in compound umbels. Small white flowers that become zygomorphic at the umbel edge are common among the Apiaceae.
Fruits of Pastinaca sativa - these dry schizocarps in umbels are the most commonly seen fruit among the Apiaceae family.
Fruits of Pastinaca sativa – these dry schizocarps in umbels are the most commonly seen fruit among the Apiaceae family.

Apiaceae Species I have Covered So Far

Apioideae Subfamily

Anthriscus sylvestris inflorescence; introduced; Squamish, BC, Canada; Apiaceae family

Anthriscus sylvestris – Cow Parsley

Herbaceous perennial, 60 – 170 cm tall with hollow, striated, and grooved stems that are green with purple splotches and tiny hairs. Leaves are 2 – 3 times pinnate, about 45 cm long, and appear fern-like. Flowers are white, small, in compound umbels, and have downy oval bracteoles with red tips on the umbelets. Peduncles are hairless and grooved. Native to Eurasia and Africa, widely introduced in the Americas.

Bifora americana plant with flowers; native endemic; Palo Pinto County, TX, USA; Apiaceae family

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, petals have notched tips. Fruit is schizocarp. Endemic to the southern USA in Texas, Oklahoma, and Arkansas. This was in Palo Pinto County, TX, USA.

Chaerophyllum procumbens plant; North American Endemic; Acworth, GA, USA; Apiaceae family

Chaerophyllum procumbens – Spreading Chervil

Herbaceous annual 15 – 50 cm tall from slender branching shiny and finely hairy stems. Mostly hairless doubly compound pinnate leaves are fern-like in appearance. Flowers in small terminal compound umbels with 2 – 6 umbellets, each with 1 – 7 small white flowers that bloom before the umbel finishes expanding. Endemic to eastern North America.

Chaerophyllum tainturieri flowers & leaves; USA endemic; Suffolk, VA, USA

Chaerophyllum tainturieri – Hairyfruit Chervil

Herbaceous annual to 80 cm tall with erect stems, opposite bipinnately compound hirsute leaves. Flowers in few-flowered axillary umbels (not compound). Fruit is an oblong schizocarp. Native to the southeastern USA with disjunct populations in Arizona and New Mexico. This one was in Suffolk, VA, USA.

Cicuta douglasii plant in spring; North American endemic; Sechelt, BC, Canada

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 alternate compound pinnate with 3 – 10 cm leaflets with jagged margins. Flowers in 12.5 cm compound umbels with numerous small white flowers. The most poisonous plant native to North America; endemic to the Pacific Northwest, mostly in BC, Canada.

Cicuta maculata plant; North America endemic; Lake of Ozarks, MO, USA

Cicuta maculata – Spotted Cowbane

Herbaceous, rhizomatous perennial with a hollow, erect stem to 1.8 m tall. Compound leaves with several lanceolate, pointy-tipped, serrated leaflets 2 – 10 cm long each. Flowers in compound umbels with many white or whitish flowers. The whole plant is poisonous. Native throughout North America from northern Canada to southern Mexico.

Conium maculatum plant with flowers; introduced species; Sunspot, NM, USA

Conium maculatum – Poison Hemlock

Herbaceous biennial 1.5 – 2.5 m tall, hairless, with smooth, green, hollow stems usually streaked with red or purple. Leaves are 2 – 4 times pinnately compound, finely divided, and lacy, 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.

Cyclospermum leptophyllum plant with floral buds; introduced; Acworth, GA, USA

Cyclospermum leptophyllum – Marsh Parsley

Herbaceous summer annual with branching stems up to 60 cm tall. Leaves are finely dissected and compound, with narrow leaflets. Flowers in small umbels are tiny and white and tinged with pink. Native around the world in tropical and warm temperate environments. Introduced in North America. This one was in Acworth, GA, USA.

Cymopterus glomeratus plant with flowers; North America endemic; Grand, UT, USA

Cymopterus glomeratus – Fendler’s Springparsley

Herbaceous perennial from a large taproot with a basal rosette of 2 – 3 times pinnately compound leaves. Flowers are in compound umbels in white, yellow, or purple. Fruit is a schizocarp with two flat, wide mericarps each containing one seed. Native to North America from southern Canada to northern Mexico. This one was in Grand, UT, USA.

Cymopterus lemmonii inflorescence; USA endemic; Cloudcroft, NM, UT, USA; Apiaceae family

Cymopterus lemmonii – Alpine False Spring Parsley

Herbaceous perennial to about 60 cm tall with pinnately compound leaves with sparse, narrow linear leaflets. Flowers in compound terminal umbels, densely packed, in yellow, orange-purple, or purple with petals that fold inwards at their tips. Grows from 5500 – 12000 ft ASL. Endemic to the west and southwestern USA. This was in Cloudcroft, NM.

Daucus carota inflorescence; introduced; Pike, IL, USA; Apiaceae family

Daucus carota – Wild Carrot

Herbaceous biennial 30 – 120 cm tall with a roughly hairy, stiff, solid stem. Tripinnate, finely divided leaves are 5 – 15 cm long, alternate. Flowers are small, whitish, in dense flat-topped terminal umbels 8 – 15 cm wide. Fruits are schizocarps that develop as the umbels contract and become congested. Native throughout the temperate Old World and widely introduced in the Americas.

Heracleum mantegazzianum plant; introduced invasive; West Sechelt, BC, Canada; Apiaceae family

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 incised margins. White or green-white flowers in compound umbels, flat-topped, up to 1 m across. Flowers may be radially or bilaterally symmetric. Eurasian native; widely introduced and invasive. Causes phototoxicity and contact dermatitis.

Heracleum maximum plant with flowers; North America native; Squamish, BC, Canada; Apiaceae family

Heracleum maximum – Cow Parsnip

Herbaceous perennial plant to 3 m tall with hollow, densely hairy stems that have no purple splotches. Leaves are deeply 3-lobed but not incised, up to 40 cm across. White flowers in compound umbels to 12″ 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 ambiguum plant; North America endemic; Peachland BC, Canada; Apiaceae family

Lomatium ambiguum – Wyeth Biscuitroot

Herbaceous perennial 6 – 24 cm tall with purplish stems and pinnately compound leaves. Flowers are yellow in compound umbels. Native to northwest USA and southern BC, Canada. This was in Peachland BC, Canada.

Lomatium dissectum inflorescence; North America endemic; Lolo Forest, MT, USA; Apiaceae family

Lomatium dissectum – Fernleaf Biscuitroot

Herbaceous perennial to 1.2 m tall from a thick taproot; leaves mostly basal with petioles to 30 cm long and pinnately compound leaves with narrow leaflets. Flowers are yellow or reddish in compound umbels on a leafless peduncle 10 cm long. Fruit is an ovate schizocarp. Native throughout western North America. This was in Lolo Forest, MT, USA.

Lomatium foeniculaceum plant; North America endemic; Gloss Mountain, OK, USA; Apiaceae family

Lomatium foeniculaceum – Desert Biscuitroot

Herbaceous perennial herb to 30 cm tall from a taproot; stemless; pubescent leaf petioles and peduncle grow from the ground. Leaves are 2 – 4 times compound pinnate to 30 cm long. Flowers are small yellow, or purplish in compound umbels. The plant smells and tastes of parsley. Native to west and central North America. Photo Gloss Mountain, OK, USA.

Lomatium multifidum plant; North America endemic; Edgewood, BC, Canada; Apiaceae family

Lomatium multifidum – Fernleaved Desert Parsley

Herbaceous perennial 30 – 140 cm; hairless, puberulent, or scabrous with a scarious sheath at the base. Leaves 3 times compound pinnate 15 – 35 cm wide on 3 – 30 cm petiole. Yellowish flowers in compound umbels with about as many bractlets as flowers. Fruit a hairless schizocarp with thick wings. Native to western North America from BC, Canada, south to Baja California, Mexico.

Osmorhiza berteroi flowers; native to North America; Edgewood, BC, Canada; Apiaceae family

Osmorhiza berteroi – Mountain Sweet Cicily

Fragrant herbaceous perennial with a branching stem to 1m tall. Trifolate leaves up to 20 cm long with toothed or lobed margins and a long petiole. Small whitish flowers in terminal compound umbels with 4 – 10 flowers in each umbellet; central flowers often have only anthers. Fruit is elongated ribbed and bristly schizocarp to 2.5 cm long. Native to temperate North and South America.

Pastinaca sativa plant; introduced; Sangamon County, IL, USA; Apiaceae family

Pastinaca sativa – Wild Parsnip

Herbaceous biennial/perennial to 1.2 m tall; smells like parsnip. Leaves are alternate and compound pinnate. Leaflets are yellow-green, rhombic, and coarsely serrated. Numerous yellow flowers in compound umbles. Fruit is a schizocarp with two flattened, slightly winged mericarps. May cause photosensitivity. Native to Eurasia, widely introduced in the Americas and considered invasive.

Sium suave plant with flowers; native North America; Ross Coastal Plain Reserve, MI, USA; Apiaceae family

Sium suave – Water Parsnip

Herbaceous perennial to 3 m tall with light green hairless stems up to 5 cm thick with few branches. Leaves in basal rosettes or in clusters in aquatic habitats; those on stem are alternate and odd-pinnate. Flowers in small compound umbels with 10 – 20 small white flowers. Fruit is an indehiscent schizocarp. Native to Eurasia and North America.

Torilis arvensis flowers; introduced; Nashville, TN, USA; Apiaceae family

Torilis arvensis – 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 lanceolate leaflets up to 6 cm long each. 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. Native to Europe, introduced in North America. Nashville, TN, USA

Azorelloideae Subfamily

Bowlesia incana plants; native to North America; Nashville, TN, USA; Apiaceae family

Bowlesia incana – Hoary Bowlesia

Small herbaceous annual with thin, spreading stems to 60 cm long. Leaves on long petioles are multi-lobed, to 3 cm, with a round to reniform shape; surfaces are finely pubescent to puberulent. Yellow-green flowers are in small axillary clusters. Tiny inflated fruit is 2 mm wide. Native from southwestern and southeastern USA south to South America. Spreading outside its native range due to its ability to grow in lawns.

Saniculoideae Subfamily

Eryngium yuccifolium inflorescence; endemic North America; Nashville, TN, USA; Apiaceae family

Eryngium yuccifolium – Rattlesnake Master

Herbaceous perennial to 1.8 m tall with 15 – 100 cm long, stiff, 1 – 3 cm wide, sharp-tipped glaucous blue-green leaves with spiny margins. Flowers 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 it, with another cluster of spiny bracts beneath the round umbel. Native to tall grass prairies of central and eastern USA.

Sanicula canadensis plant; endemic North America; Nashville, TN, USA; Apiaceae family

Sanicula canadensis – Canadian Blacksnake Root

Herbaceous biennial or perennial 0.3 – 1.4 m tall with usually trifoliate leaves with ovate, obovate, or broadly elliptic leaflets. Small pale green flowers in tiny bur-like compound umbels have sepals longer than their petals, followed by bur-like schizocarps with two mericarps. Native to eastern North America, west to Wyoming, USA. This was in Nashville, TN.

Sanicula odorata plant with fruits; native North America; Nashville, TN, USA; Apiaceae family

Sanicula odorata – Common or Clustered Blacksnake Root

Herbaceous perennial with compound leaves divided into 5 or sometimes 7 leaflets on the lower leaves with the upper leaves sometimes divided into 3. Flowers and anthers are small in dense bur-like compound umbels with styles and petals both longer than the sepals. Native throughout eastern North America. This was in Nashville, TN, USA.

Taxonomy of Apiaceae

3789-3820 spp in 440-446 genera of the Apiales Order of the core Eudicots. This family is divided into four main subfamilies.

  1. Apioideae – The largest subfamily and a diverse group of annual to perennial herbs or subshrubs or rarely to a small tree. Leaves are usually palmately divided but may be pinnate or simple and entire. Venation is pinnate, but some have parallel. Fruits are variable and may or may not be flattened, winged, or ribbed. Cosmopolitan distribution. 
  2. Azorelloideae – Annual herbs or small shrubs, often hummock-forming.  Leaves are simple, trifid to palmately lobed, stipulate. Fruit with wings or ribs where the wings or ribs are the largest. Mostly South American, particularly the Patagonia region.
  3. Mackinlayoideae – Annual herbs to shrubs. Leaves may or may not be pedately compound, palmate to simple, and are stipulate. Fruit is drupaceous and often laterally compressed. Mostly Old World Tropics.
  4. Saniculoideae – A diverse group of annual herbs and subshrubs to trees. Leaves may be tripinnately or palmately compound or simple and often pamately lobed, and some have hairy or spiny teeth. Inflorescences are usually simple umbels or capitulum, and bracts may be foliaceous or petaloid. Fruits may be barely to strongly compressed dorsally or laterally, may have 2-3 wings, or maybe scaly or spiny. Cosmopolitan distribution.    

Genera:

Apioideae: Aciphylla (46), Acronema (34), Actinanthus (1), Actinolema (2), Adenosciadium (1), Aegokeras (1 inc Olymposciadium), Aegopodium (11 inc Chamaele), Aethusa (1), Afroligusticum (14), Afrosciadium (18), Agasyllis (1), Alepidea (31), Ammi (3), Ammodaucus (1), Ammoides (3), Ammoselinum (4), Andriana (3), Anethum (2), Angelica (104 inc Sphenosciadium), Anginon (12), Angoseseli (1), Anisopoda (1), Anisosciadium (3), Anisotome (17), Annesorhiza (18), Anthriscus (13), Aphanopleura (5), Apiastrum (1), Apium (12), Apodicarpum (1), Arafoe (1), Arctopus (3), Arcuatopterus (5), Arracacia (42), Artedia (1), Asciadium (1), Astomaea (2), Astrantia (11 inc Transcaucasia), Astrodaucus (3), Astydamia (1), Athamanta (12 inc Tinguarra), Aulacospermum (15), Austropeucedanum (1), Autumnalia (2), Azilia (1), Berula (6 inc Afrocarum), Bifora (3), Billburttia (2), Bonannia (1), Bunium (32), Bupleurum (213), Cachrys (12 inc Bilacunaria), Calyptrosciadium (2), Canaria (1), Cannaboides (2), Capnophyllum (4), Carlesia (1), Caropodium (3), Caropsis (1), Carum (22), Caucalis (1), Cenolophium (1), Cephalopodum (3), Chaerophyllopsis (1), Chaerophyllum (69 inc Myrrhoides, Oreomyrrhis), Chaetosciadium (1), Chamaesciadium (1), Chamaesium (10), Chamarea (5 inc Trachysciadium), Changium (2), Choritaenia (1), Chuanminshen (1), Chymsydia (2), Cicuta (4), Cnidiocarpa (2), Cnidium (8), Coaxana (2), Conioselinum (16), Conium (6), Conopodium (8), Coriandrum (2), Cortia (4), Cortiella (4), Cotopaxia (2), Coulterophytum (4), Crithmum (1), Cryptotaenia (6), Cuminum (4), Cyathoselinum (1), Cyclorhiza (2), Cyclospermum (3), Cymbocarpum (5), Cymopterus (44 inc Aletes, Oreoxis, Pseudocymopterus, Pteryxia), Cynorhiza (3), Cynosciadium (1), Dactylaea (2), Dahliaphyllum (1), Dasispermum (7 inc Sonderina), Daucosma (1), Daucus (43 inc Agrocharis, Melanoselinum, Monizia, Pachyctenium, Pseudorlaya, Rouya, Tornabenea), Demavendia (1), Dethawia (1), Deverra (9), Dichoropetalum (34), Dichosciadium (1), Dickinsia (1), Dicyclophora (1), Dimorphosciadium (2), Diplaspis (3), Diplolophium (7), Diplotaenia (5), Donnellsmithia (19), Dracosciadium (2), Drusa (1), Ducrosia (6), Dystaenia (2), Echinophora (11), Ekimia (4), Elaeosticta (25 inc Muretia), Eleutherospermum (1), Elwendia (27), Enantiophylla (1), Endressia (2), Eremodaucus (1), Ergocarpon (1), Erigenia (1), Eurytaenia (2), Exoacantha (1), Ezosciadium (1), Falcaria (1), Fergania (1), Ferula (213 inc Dorema, Eriosynaphe, Schumannia, Soranthus), Ferulago (47), Ferulopsis (2), Foeniculum (3), Frommia (1), Froriepia (2), Fuernrohria (1), Galagania (5 inc Korovinia), Geocaryum (2), Gingidia (12), Glaucosciadium (2), Glehnia (1), Glia (3), Gongylosciadium (1), Gongylotaxis (1), Grafia (1), Grammosciadium (4), Halosciastrum (1), Haloselinum (1), Hansenia (5 inc Haplosphaera, Notopterygium), Haplosciadium (1), Harbouria (1), Harperella (1),  Harrysmithia (2), Haussknechtia (1), Hellenocarum (3), Helosciadium (4), Heptaptera (8), Heracleum (86 inc Wendia), Heteromorpha (8 inc Aframmi), Hladnikia (1), Hohenackeria (2), Homalocarpus (6), Homalosciadium (1), Horstrissea (1), Hyalolaena (9), Hymenidium (39), Hymenolaena (3), Itasina (1), Johrenia (5), Kadenia (2), Kafirnigania (1), Kailashia (2), Kalakia (1), Kamelinia (1), Kandaharia (1), Karatavia (1), Karnataka (1), Kedarnatha (6), Kelussia (1), Kenopleurum (1), Keraymonia (4), Kitagawia (9), Klotzschia (3), Komarovia (1),  Korshinskia (4), Kozlovia (2), Krasnovia (1), Krubera (1), Kundmannia (3 inc Arduina), Kuramosciadium (1), Ladyginia (3 inc Spongiosyndesmus), Lagoecia (1), Lalldhwojia (4), Laser (7 inc Polylophium), Laserpitium (10), Lecokia (1), Ledebouriella (1), Lefebvrea (8 inc Erythroselinum), Leiotulus (10), Lereschia (1), Leutea (9), Levisticum (1), Lichtensteinia (6), Lignocarpa (2), Ligusticopsis (17), Ligusticum (40), Lilaeopsis (13), Limnosciadium (1), Lipskya (1), Lisaea (3), Lithosciadium (2), Lomatium (101 inc Orogenia), Lomatocarpa (3), Lomatocarum (1), Magadania (2), Magydaris (2), Marlothiella (1), Mastigosciadium (1), Mathiasella (1), Mediasia (1), Meeboldia (2 inc Sinodielsia), Melanosciadium (3), Meum (1), Modesciadium (1), Mogoltavia (2), Molopospermum (1), Musineon (6), Mutellina (3), Myrrhidendron (5), Myrrhis (1), Nanobubon (3), Naufraga (1), Neoconopodium (1), Neogaya (1), Neogoezia (5), Neomuretia (2), Neonelsonia (1), Neoparrya (1), Niphogeton (18), Nirarathamnos (1), Normantha (1), Nothosmyrnium (2), Notiosciadium (1), Notobubon (12), Oedibasis (4), Oenanthe (33), Oligocladus (1), Oliveria (1), Opoidia (1), Opopanax (4 inc Crenosciadium), Opsicarpium (1), Oreocome (8), Oreocomopsis (3), Oreonana (3), Oreoschimperella (3), Orlaya (3), Ormopterum (2), Ormosciadium (1), Osmorhiza (12), Ostericum (11), Ottoa (1), Oxypolis (4), Pachypleurum (2), Palimbia (3), Paraligusticum (1), Parapimpinella (1), Paraselinum (1), Parasilaus (2), Pastinaca (15 inc Malabaila), Pastinacopsis (1), Paulita (2), Pedinopetalum (1), Perideridia (13), Perissocoeleum (4), Petroedmondia (1), Petroselinum (1 inc Wydleria), Peucedanum (71 inc Imperatoria), Phellolophium (1), Phlojodicarpus (3), Phlyctidocarpa (1), Physospermopsis (8), Physospermum (2), Physotrichia (6 inc Spuriodaucus), Pilopleura (2), Pimpinella (152 inc Afrosison, Albovia), Pinda (1 inc Polyzygus), Pleurospermopsis (1), Pleurospermum (13), Podistera (4), Polemannia (3), Polemanniopsis (2), Polytaenia (3), Portenschlagiella (1), Postiella (1), Prangos (48 inc Alococarpum, Neocryptodiscus), Prionosciadium (21), Psammogeton (8), Pseudocannaboides (1), Pseudocarum (2), Pseudoridolfia (1), Pseudoselinum (1), Pseudotrachydium (5), Pternopetalum (20), Pterygopleurum (1), Ptilimnium (5), Ptychotis (2), Pycnocycla (15), Pyramidoptera (1), Registaniella (1), Rhabdosciadium (8), Rhizomatophora (1), Rhodosciadium (15), Rhopalosciadium (1), Rhysopterus (1), Ridolfia (1), Rivasmartinezia (2), Rohmooa (1), Rupiphila (1), Rutheopsis (1), Sajanella (1), Saposhnikovia (1), Scaligeria (6), Scandia (2), Scandix (12), Scaraboides (1),Schoenoselinum (1), Schrenkia (12 inc Kosopoljanskia), Schtschurowskia (2), Schulzia (4), Sclerochorton (1), Sclerosciadium (1), Sclerotiaria (1), Scrithacola (1), Selinopsis (2), Selinum (11), Semenovia (27 inc Merwiopsis, Neoplatytaenia), Seseli (144 inc Eriocycla, Lomatopodium, Sphenocarpus), Seselopsis (2), Shoshonea (1), Siculosciadium (1), Silaum (1), Siler (4), Sillaphyton (1), Silphiodaucus (2), Sinocarum (19),  Sinolimprichtia (1), Sison (2), Sium (10), Sivadasania (1), Smyrniopsis (2), Smyrnium (5), Spananthe (2), Spermolepis (11), Sphaenolobium (3), Sphaerosciadium (1), Sphallerocarpus (1), Spiroceratium (1), Spuriopimpinella (6), Stefanoffia (2), Steganotaenia (3), Stenocoelium (4), Stenosemis (2), Stenotaenia (5), Stewartiella (1), Stoibrax (3), Symphyoloma (1), Synclinostyles (2), Szovitsia (1), Taenidia (2), Taeniopetalum (2), Tamamschjanella (2), Tamamschjania (1), Tana (1), Tauschia (34), Tetrataenium (20), Thamnosciadium (1), Thapsia (20 inc Elaeoselinum), Thaspium (4), Thecocarpus (2), Tiedemannia (2), Tilingia (2), Todaroa (1), Tongoloa (15), Tordyliopsis (1), Tordylium (20 inc Ainsworthia, Synelcosciadium), Torilis (14), Trachydium (12), Trachyspermum (20), Trepocarpus (1), Tricholaser (2), Trigonosciadium (6 inc Mandenovia), Trinia (9 inc Rumia), Trocdaris (1), Trochiscanthes (1), Tschulaktavia (1), Turgenia (2), Turgeniopsis (1 inc Glochidotheca), Vanasushava (1), Vesper (6), Vicatia (5), Villarrealia (1), Vinogradovia (1), Visnaga (2). Vvedenskya (1), Xanthogalum (3), Xatardia (1), Xyloselinum  (3), Yabea (1), Zeravschania (12), Zizia (3), Zosima (4).

Azorelloideae: Asteriscium (9), Azorella (53 inc Laretia, Mulinum, Schizeilema), Bolax (2), Bowlesia (16), Diposis (3), Domeykoa (5), Eremocharis (9), Gymnophyton (6), Huanaca (2), Microsciadium (1), Oschatzia (2), Pozoa (2), Schizeilema (?), Stilbocarpa (?).

Mackinlayoideae: Actinotus (20), Apiopetalum (2), Brachyscias (1), Centella (50), Chlaenosciadium (1),  Mackinlaya (5), Micropleura (2), Pentapeltis (2), Schoenolaena (1), Xanthosia (20).

Saniculoideae: Eryngium (247), Hacquetia (?), Petagnia (inc Petagnaea) (1), Sanicula (47 inc Hacquetia).

Unplaced: Hermas (9), Platysace (23).

Key Differences From Similar Families

Apiaceae are both similar to and closely related to Araliaceae, 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 Apiaceae vs usually present in Araliaceae, and the fruit is a dry schizocarp with two mericarps vs a berry-like drupe in the Araliaceae.

Distribution of Apiaceae

The Apiaceae are found in frigid to tropical zones and are cosmopolitan but mainly North temperate.

Distribution of Apiaceae in the Americas

Canadian Genera Include:

Apioideae:Aegopodium 1 of 11 Eurasian spp intro all S Canada exc AB, Labrador; Aethusa monospecific European sp intro ON, QC, NB, NS; Anethum 1 of 2 Mediterranean spp intro all S provinces exc NS, NB, PE, NL; Angelica  9 of 104 N temperate spp native all of Canada (& GL) exc SK, MB; Anthriscus 3 of 13 mostly Eurasian spp intro BC, ON, QC, NB, NS NL (exc Labrador); Apium 1 of 12 temperate & subtropical Old World & SAM spp native extirpated NS; Astrantia 1 of 11 S European spp intro NL (exc Labrador); Berula 1 of 6 subcosmopolitan spp native BC, ON; Bunium 1 of 32 Mediterranean & Indian spp intro NL?; Bupleurum 2 of 213 sub cosmopolitan spp native YT, AB, NT, BC intro QC, ON; Carum  1 of 22 Eurasian spp intro all Canada exc YT, Labrador; Chaerophyllum 3 of 69 mostly N temperate spp intro BC, native ON, QC?; Cicuta 4 of 4 N temperate spp native all of Canada inc Arctic; Cnidium 1 of 8 mostly E Asian spp native BC, YT, NT; Conioselinum 2 of 16 N temperate spp native BC, ON, NL, NB, NS, PE; Conium 1 of 6 mostly Eurasin spp intro BC, AB, SK, ON, QC, NB, NS; Conopodium 1 of 8 Eurasian spp intro NL (exc Labrador); Coriandrum 1 of 2 Middle East spp intro ON, QC, NS; Cryptotaenia 1 of 6 mostly African spp a former NAM endemic native in MB, ON, QC, extirpated NB, now intro Austria; Cymopterus 1 of 44 NAM endemic spp native BC?, AB, SK, MB; Daucus 1 of 43 cosmopolitan spp native BC intro rest of S provinces; Erigenia monospecific E NAM endemic sp native ON; Foeniculum 1 of 3 Mediterranean spp intro BC, ON, QC, cultivated fennel; Glehnia monospecific E Asia & NW NAM sp native BC; Heracleum 4 of 83 mostly Eurasian spp inc 1 sp native all Canada exc NU and 3 spp intro BC, YT, ON, QC, NB, NS, PE, NL (exc Labrador); Levisticum monospecific Middle Eastern sp intro AB, ON, QC, NS; Ligusticum 6 of 40 N temperate spp native BC, ON, QC, NL, NS, NB, PE, NU (& GL); Lilaeopsis 2 of 13 Americas & Australasia spp native BC, NS; Lomatium 20 of 101 W+C NAM endemic spp native BC, AB, SK, MB; Musineon 1 of 6 spp C NAM endemic spp native AB, SK, MB; Myrrhis monospecific S Europe sp intro BC, ON, NS, NL (exc Labrador); Oenanthe 1 of 33 mostly N temperate spp native BC; Osmorhiza 6 of 12 mostly Americas spp native all of Canada, 1 sp native temperate Asia; Oxypolis 2 of 4 NAM endemic spp native BC, ON; Pastinaca 1 of 15 Eurasian spp intro all of Canada exc NU, Labrador; Perideridia 1 of 13 NAM endemic spp native BC, AB, SK; Petroselinum monospecific Mediterranean sp (parsley) intro BC, ON; Peucedanum (inc Imperatoria) 1 of 71 Eurasian spp intro ON, NS; Pimpinella 2 of 152 Old World spp intro AB, ON, QC, NB, NS, NL (exc Labrador); Podistera 2 of 4 temperate NE Asia & NW NAM spp native YT, NT; Scandix 1 of 12 Mediterranean & C Asia spp intro BC?, SK?, ON?; Sium 1 of 10 N temperate spp native all Canada inc Arctic, exc Labrador; Taenidia 1 of 2 E NAM endemic spp native ON, QC; Thaspium 3 of 4 E NAM endemic spp native ON, NS; Torilis 3 of 14 Old World spp intro BC, ON, QC; Yabea monospecific W NAM endemic sp native BC; Zizia 2 of 3 N NAM endemic spp native all S Canada ex PE, NL, inc YT. Saniculoideae: Eryngium 4 of 247 subcosmopolitan spp intro BC, AB, SK, ON, QC; Sanicula 9 of 47 cosmopolitan spp native all of S Canada exc Labrador.  

USA Genera Include:

Apioideae: Aegopodium 1  of 11 Eurasian spp intro 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, ME; Aethusa monospecific European sp intro ID, AR, MN, WI, IL, IN, OH, KY, MI, WV, PA, DE, NJ, NY, CT, RI, MA, ME; Ammi 2 of 3 Mediterranean & Azores spp intro OR, CA, AZ, TX, LA, MS, AL, GA, FL, SC, NC, MO, SD, PA; Ammoselinum 3 of 4 Americas endemic spp native CA, AZ, NM, TX, LA, OK, KS, AR, MO, MS, TN, NC, intro AL, inc 1 S USA endemic sp; Anethum 1 of 2 Mediterranean spp intro in most USA exc ID, NV, UT, WY, NM, TN, MS, AL, GA, SC, FL, VT, NH and inc HI; Angelica 22 of 104 N temperate spp native all USA inc AK but exc ND, SD, NE, KS, TX; Anthriscus 3  of 13 mostly Eurasian spp intro 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, ME; Apiastrum monospecific SW NAM endemic sp native CA, AZ; Apium 4 of 12 temperate & subtropical Old World & SAM 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, MA; Berula 1 of 6 subcosmopolitan spp native all W USA from MN S to LA and all states W exc LA and inc MI, NY; Bifora 3 of 3 American & Mediterranean spp inc 1 sp endemic S USA in TX, OK, AR and 2 spp intro AL, PA, MD, NJ, RI; Bupleurum 4 of 213 sub cosmopolitan spp native AK, native and intro most of USA exc WA, NV, UT, ND, NE, OK, MN, IA, WI, RI, ME, MS, SC; Carum 1 of 22 Eurasian spp intro all N half of USA from OR E to NJ and all N exc NE and inc UT, CO, NM, LA, MO, TN, KY, WV, VA, MD, NC; Caucalis monospecific Mediterranean sp intro PA and HI; Chaerophyllum 4 of 69 mostly N temperate spp intro and native most E USA ND S to TX and all E exc ND, SD, MN, CT, MA, VT, NH, ME and inc AZ, NM; Cicuta 4 of 4 N temperate spp native all USA inc AK; Cnidium 2 of 8 mostly E Asian spp ink 1 sp native AK and 1 sp intro OR; Conioselinum 4 of 16 N temperate spp native most of USA inc AK exc ID, NV, ND, SD, KS, OK, TX, AR, MS, AL, SC, FL, TN, KY, WV, MD, DE; Conium 1 of 6 mostly Eurasian spp intro all USA exc MS, FL; Coriandrum 1 of 2 Middle East spp intro 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 of 6 mostly African spp a former NAM endemic native all E USA from ND S to TX and every state E, now intro Austria; Cuminum 1 of 4 Middle East & C-W Asia spp intro TX, MA; Cyclospermum 1 of 3 former Mexico & Neo endemic sp intro all S USA NM E to NC and inc CA, NV, OR, IL, VA, WV, MD, PA, NY and HI; Cymopterus (inc Aletes, Oreoxis, Pseudocymopterus, Pteryxia) 43 of 44 spp native to all W half of USA from ND S to TX but exc WA, inc MN; Cynosciadium monospecific S USA endemic of TX, OK, LA, AR, MO, IL, TN, MS, AL; Daucosma monospecific narrow endemic of NM, TX; Daucus 1 of 43 cosmopolitan spp native and intro all USA; Erigenia monospecific E NAM endemic sp native most of E USA WI S to MS and all E exc FL, SC, DE, NJ, CT, RI, MA, VT, NH, ME and inc KS, OK, MO, AR; Eurytaenia 2 of 2 S USA endemic spp of NM, TX, OK, inc 1 narrow endemic of TX; Falcaria monospecific Eurasian sp intro WY, SD, NE, OK, LA, IA, MO, WI, IL, WV, VA, MD, PA, NY, CT; Foeniculum 1 of 3 Mediterranean spp intro most of USA exc ID, MT, WY, CO, ND, SD, OK, MN, AL, VT, NH and inc HI, cultivated fennel; Glehnia monospecific E Asia & NW NAM sp native WA, OR, CA; Harbouria monospecific C USA endemic of WY, CO, NM; Harperella monospecific SE USA endemic of AL, AK, MS, GA, SC, NC, VA, MD, OK; Helosciadium 1 of 4 Eurasian & African spp intro CA, PA, NJ; Heracleum 3 of 83 mostly Eurasian spp inc 1 sp native and 2 spp intro most USA exc TX, OK, AR, LA, MS, AL, FL, SC, and native AK; Levisticum monospecific Middle Eastern sp intro intro CO, NM, MO, MN, MI, OH, PA, NJ, NY, CT, MA, VT, ME; Ligusticum 11 of 40 N temperate spp native all W and E states inc AK but exc ND S to TX and also exc MN, IA, LA, FL, WI, IL, MI, VT; Lilaeopsis 6 Americas & Australasia spp native WA, OR, CA, AZ, TX, LA, AR, MS, AL, FL, GA, SC, VA, NC, MD, NY, NJ, MA, NH, ME and AK; Limnosciadium monospecific S+E USA endemic of TX, OK, KS, LA, AR, MS, MO, IA; Lomatium (inc Orogenia) 89 of 101 W+C NAM endemic spp native all W USA MN S to LA and all W exc AR, LA, most are narrow endemics of the USA; Musineon 6 of 6 C NAM endemic spp native ID, MT, WY, CO, NV, UT, NM, ND, SD, NE, inc 4 endemic to the USA which inc 3 narrow endemics of MT (1), ID + UT (2); Myrrhis monospecific S Europe sp intro OR, MI, PA; Neoparrya monospecific narrow S-C USA endemic of NM, CO; Oenanthe 4 of 33 mostly N temperate spp native WA, OR, CA and AK and intro MO, OH, MD; Oreonana 3 of 3 narrow endemic spp of CA; Osmorhiza 8 of 12 mostly Americas spp native all USA inc AK but exc FL, LA, inc 1 endemic to USA, 1 sp in genus native temperate Asia; Oxypolis 4 of 4 NAM endemic spp native all USA exc WA, ID, WY, NV, ND, SD, NE, KS, inc 2 spp endemic to S USA; Pastinaca 1 of 15 Eurasian spp intro in all USA exc MS, AL, GA, FL; Perideridia 13 of 13 NAM endemic spp native most of USA exc all E and NE Atlantic states as well as WV,  TX, LA, NE, ND, MN, IA, WI, inc 12 spp endemic to USA; Petroselinum monospecific Mediterranean sp (parsley) intro 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 of 71 mostly Eurasian spp intro TN, PA, NY, WV, MA, native HI; Pimpinella 3 of 152 Old World spp intro WA, MT, MN, WI, TN, IN, MI, OH, VA, WV, MD, DE, PA, NJ, NY, CT, MA, VT, ME; Podistera 4 of 4 NE Asia & NW NAM spp native CA, UT, CO, NM and AK; Polytaenia 3 of 3 E USA endemic spp of ND, NE, KS, OK, TX, MN, IA, MO, AR, LA, MS, AL, TN, KY, WI, IL, IN, MI; Ptilimnium 5 of 5 USA & Caribbean endemic spp native in most of SE USA from KS S to TX and E to NJ exc IN, OH and inc SD, NY, CT, RI, MA, inc 4 spp endemic to USA; Rhysopterus monospecific W USA endemic OR, ID, NV; Scandix 1  of 12 Mediterranean & C Asia spp intro WA, OR, CA, AZ, TX, SD, AL, GA, FL, SC, NC, TN, OH, MI, PA, MD, NJ, NY, RI, MA; Selinum 1 of 11 mostly European spp intro MA, NY?; Seseli 1 of 144 mostly Eurasian spp intro MD; Shoshonea monospecific narrow endemic of WY, MT; Sium 2 of 10 N temperate spp native all USA inc AK but exc OK; Smyrnium 1 of 5 Mediterranean spp intro AL; Spermolepis 9 of 11 Americas endemic spp native in most of S+E USA from ND S to TX and all E exc WI, MI, OH, WV, PA, CT, RI, MA, VT, NH, ME and inc NM, AZ, CA and HI, inc 6 endemic to USA, 5 of which are narrow endemics of SW CA (1), TX (1), AZ + CA(extirpated) (1), NM (1), HI (1); Taenidia 2 of 2 E NAM endemic spp native in all E half of USA from ND S to TX and all E exc ME, NH, CT, FL, ND, NE, inc 1 narrow endemic of NE USA; Tauschia 10 of 34 Americas endemic spp native WA, ID, OR, CA, TX; Thaspium 4 of 4 spp endemic E NAM native all E USA from ND S to TX and all E exc ND, SD, NE, CT, MA, VT, NH, ME, inc 1 sp endemic to E USA; Tiedemannia 2 of 2 S USA & Caribbean endemic spp native TX, LA, MS, AL, GA, FL, SC, NC, MD, extirpated DE, inc 1 sp endemic S USA; Tilingia 1 of 2 NE Asia & AK spp native AK; Tordylium 1 of 20 Mediterranean spp intro AZ; Torilis 5 of 14 Old World spp intro most of USA exc MT S to NM, also exc NV, ND, SD, MN, DE, CT, RI, VT, NH, ME and inc HI; Trachyspermum 1 of 20 Middle East & S Asia spp intro MI; Trepocarpus monospecific SE USA endemic TX, OK, LA, AR, MO, KY, TN, MS, AL, GA, FL, SC; Turgenia 1 of 2 Mediterranean + C Asia spp intro WA, OR, PA; Vesper  6 of 6 SW NAM endemic spp native CA, NV, ID, UT, AZ, WY, CO, NM, SD, NE, KS, OK, TX, inc 5 spp endemic to SW USA; Visnaga  1 of 2 Mediterranean spp intro CA, OR?, AL, TX?, FL?, NC?, PA?; Yabea monospecific W NAM endemic sp native WA, ID, OR, CA, NV, UT, AZ, NM; Zizia 3 of 3 N NAM endemic spp native in all USA exc CA, AZ, NM, inc 1 sp endemic to SE USA. Azorelloideae: Bowlesia 1 of 16 former Americas endemic spp native OR, CA, NV, AZ, NM, TX, OK, LA, MS, AL, FL, now intro France, Pakistan. Mackinlayoideae: Centella 2 of 50 mostly S Africa & pantropical spp intro and native WA, TX, LA, AR, MS, AL, GA, FL, SC, NC, VA, MD, DE, OH, NJ and intro HI. Saniculoideae: Eryngium 34 of 247 subcosmopolitan spp native and intro all USA exc UT, WY, MT, ND; Sanicula 22 of 47 cosmopolitan spp native in all USA exc AZ, UT and inc HI.

Mexico Genera Include:

Apioideae: Ammi 1 of 3 Mediterranean & Azores spp intro SW Mexico; Ammoselinum 2 of 3 Americas endemic spp native BCN, BCS, Son, Sin, Chi, Dgo, Zac, Coa, NL, Tam, SLP, Gto, Qro, Ags, Hgo; Angelica ?? of 104 N temperate spp native most of Mexico exc BCN, BCS, Son, Sin, Chp, Tab, Cam, Yuc, QR; Apiastrum monospecific SW NAM sp native BC, BCS, Son, Sin?; Apium 1 of 12 temperate & subtropical Old World & SAM spp intro NW Mexico; Arracacia ?? of 42 Mexico & Neo endemic spp native through all of Mexico; Berula 1 of 6 sub cosmopolitan spp native Nay, Jal, Col, Mch, Gro, Oax, Chp, Pue, Cam, Yuc, QR; Chaerophyllum ?? of 69 mostly N temperate spp native N+SW+C Mexico, Ver; Cicuta 2 of 4 N temperate spp native Chi, Coa, NL, Tam, Dgo, Zac, Gto, Qro, Ags, SLP, Hgo; Coaxana 2 of 2 Mexico + CAM endemic spp native Nay, Jal, Col, Mch, Gro, Oax, Chp, Cam, Tab, Yuc, QR, inc 1 narrow endemic of Gro + Oax; Conioselinum  1 of 16 N temperate spp native BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Ags, Gto, Qro, Hgo, SLP, Nay, Jal, Col, Mch, Gro, Oax; Coriandrum 1 of 2 Middle East spp intro NW+C Mexico; Coulterophytum 4 of 4 Mexico endemic spp, all narrow endemics of Mch (1), Jal (2), Dgo + Sin + Nay (1); Cuminum 1 of 4 Middle East & C-W Asia spp intro  Chi, Coa, NL, Tam, Dgo, Zac; Cyclospermum 1 of 3 former Mexico & Neo endemic spp native most of Mexico exc BC, BCS, Son, Sin where it is intro, also intro pantropical; Cymopterus ?? of 44 NAM endemic spp native much of Mexico exc Mex, Cd Mex, Mor, Tlx, Pue, Ver, Tab, Cam, Yuc, QR; Dahliaphyllum monospecific endemic of Nay, Jal, Col, Mch, Gro, Oax; Daucus ?? of 43 cosmopolitan spp native all of Mexico inc Mexican Pacific Is; Donnellsmithia 19 of 19 Mexico + N Neo endemic spp native through all of Mexico, inc 17 spp endemic to Mexico, 11 of which are narrow endemics of Coa (1), Chi (1), Dgo + Nay (1), Zac + Jal (1),  Mex + Mch (1), Oax + Chp (1), Chp (1), SW Mexico (1), SW+C Mexico (3); Enantiophylla monospecific Mexico & CAM endemic sp native much of Mexico exc Ver, Tab, Cam, Yuc, QR; Ligusticum ?? of 40 N temperate spp native BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Ags, SLP, Hgo, Gto, Qro; Lilaeopsis 1 of 13 Americas & Australasia spp native much of Mexico exc Chp, Tab, Cam, Yuc, QR; Lomatium ?? of 101 W+C NAM endemic spp native BC, BCS, Son, Sin; Mathiasella monospecific endemic NE Mexico Chi, Coa, NL, Tam, Dgo, SLP, Zac, Gto, Ags, Qro, Hgo; Musineon 1 of 6 C NAM endemic spp native Son, Chi, Coa; Myrrhidendron 1 of 5 Neo endemic spp ative Chp, Tab, Cam, Yuc, QR; Neogoezia 5 of 5 Mexican endemic spp of N+SW+C Mexico, Ver; Neonelsonia monospecific Neo endemic native Nay, Jal, Col, Mch, Gro, Oax, Chp, Tab, Cam, Yuc, QR; Oenanthe ?? of 33 mostly N temperate spp native Nay, Jal, Col, Mch, Gro; Osmorhiza 3 of 12 mostly Americas spp native most of Mexico exc SE Mexico, inc 1 narrow endemic of NL; Ottoa monospecific N Neo endemic sp native Nay, Jal, Col, Mch, Gro, Chp, Ver, Tab, Cam, Yuc, QR; Petroselinum monospecific Mediterranean sp intro Mex, Cd Mex, Mor, Pue; Prionosciadium 21 of 21 Mexico & Gautemala endemic spp native all of Mexico, inc 20 spp endemic to Mexico, which inc 8 narrow endemics of Mex + Mch (1), Coa + NL (1), Jal + Nay (1), Zac + Jal (1), SLP (1), Chi (1), Tam (1), Col (1); Rhodosciadium 15 of 15 Mexico & Guatemala endemic spp native all of Mexico, inc 14 spp endemic to Mexico, 4 of which are narrow endemics of SLP (1), Oax (1), Jal (1), Chp (1); Spananthe 1 of 2 Mexico & Neo endemic spp native in all of Mexico;  Spermolepis 4 of 11 Americas endemic spp native BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Ags, Hgo, SLP, Ver;  Tauschia ?? of 34 Americas endemic spp native all of Mexico; Torilis ?? of 14 Old World spp intro NE Mexico Coa, Chi, NL, Tam, Dgo, Zac, Gto, SLP, Qro; Vesper 1 of 6 SW NAM endemic spp native BCN, Son;  Villarrealia monospecific narrow Mexico endemic Coa, NL; Visnaga 1 of 2 Mediterranean spp intro SW Mexico;  Yabea monospecific W NAM endemic sp native NW Mexico. Azorelloideae: Bowlesia 2 of 16 former Americas endemic spp native N+C+SW Mexico. Mackinlayoideae: Centella ?? of 50 mostly S Africa & pantropical spp native Chi, Coa, Dgo, NL, Tam, Zac, Gto, Qro, Ags, SLP, Hgo; Micropleura 1 of 2 Mexico & N Neo endemic spp native all of Mexico. Saniculoideae: Eryngium ?? of 247 subcosmopolitan spp native all of Mexico; Sanicula ?? of 47 cosmopolitan spp native all of Mexico. 

Neotropical Genera Include:

Apioideae: Ammi 2 of 3 Mediterranean & Azores spp intro Bermuda, Bahama, Cuba, Hispaniola, Guatemala, El Salvador, Colombia, Argentina, S Brazil, Uruguay; Ammoselinum 1 of 4 Americas endemic spp a narrow endemic of NE Argentina + Uruguay; Anethum 1 of 2 Mediterranean spp intro Guatemala, Bahamas, Greater Antilles, Leeward & Windward Is, Ecuador, Peru, NE Argentina, S+SE Brazil; Anthriscus ??  of 13 mostly Eurasian spp intro C Chile, NW Argentina; Apium 9 of 12 temperate & subtropical Old World & SAM spp inc 8 spp native Bolivia, Chile, Juan Fernandez Is, Desventurados Is, Argentina, Paraguay, S+SE Brazil, Uruguay and 1 sp intro intro Guatemala, Bermuda, Cuba, Hispaniola, Puerto Rico, Trinidad-Tobago, Ecuador, Peru, inc 4 narrow endemic of N+C Chile + Juan Fernandez Is (1), Juan Fernandez Is (1), C Chile (1), Uruguay (1); Arracacia 42 of 42 Mexico & Neo endemic spp of Mexico, Guatemala, El Salvador, Honduras, Costa Rica, Panama, Andes of Colombia, Venezuela, Ecuador, Peru, Bolivia, intro Cuba, Hispaniola, Jamaica, Puerto Rico, Trinidad-Tobago; Asciadium monospecific endemic Cuba; Austropeucedanum monospecific endemic NW Argentina; Berula 1 of 6 subcosmopolitan spp native Guatemala; Bupleurum 1 of 213 subcosmopolitan spp intro NE Argentina; Caucalis monospecific Mediterranean sp intro NE Argentina; Chaerophyllum ?? of 69 mostly N temperate spp native Guatemala, Costa Rica, Colombia, Ecuador, Peru, Bolivia, Argentina; Coaxana 1 of 2 Mexico & CAM endemic spp native Guatemala, Honduras; Conium 1 of 6 mostly Eurasian spp intro Guatemala, Honduras, El Salvador, Cayman Is, Hispaniola, Colombia, Ecuador, Peru, Bolivia, S+SE Brazil, Argentina, C+S Chile; Coriandrum 1 of 2 Middle East spp widely cultivated and naturalized Cuba, Hispaniola, Puerto RIco, Trinidad-Tobago, Juan Fernandez Is, Ecuador, Peru, Paraguay, S Brazil, Argentina; Cotopaxia 2 of 2 N SAM endemic spp of the high Andes of Ecuador, Colombia; Cyclospermum 3 of 3 former Mexico & Neo endemic spp native CAM (exc Belize), Colombia, Venezuela, Ecuador, Galapagos, Peru, Bolivia, C+E+S Brazil, Paraguay, Chile, Argentina, Uruguay, intro Bermuda, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Juan Fernandez Is, USA & pantropical, inc 1 narrow endemic of Uruguay; Daucus 3 of 43 cosmopolitan spp native Mexico, Guatemala, El Salvador, Honduras, Colombia, Venezuela, Ecuador, Peru, Bolivia, S+SE Brazil, Chile, Argentina, Uruguay, and intro Greater Antilles (exc Cayman Is), Leeward Is, Trinidad-Tobago, Juan Fernandez Is, Desventurados Is; Donnellsmithia 2 of 19 Mexico & N Neo endemic spp native Guatemala, El Salvador, Honduras, Nicaragua, Panama, Colombia, Venezuela, most of genus is endemic to Mexico; Enantiophylla monospecific Mexico & CAM endemic sp native Guatemala, El Salvador, Honduras; Foeniculum 1 of 3 Mediterranean spp intro cultivated and naturalized, Bermuda, Bahamas, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Guatemala, El Salvador, Colombia, Ecuador, Peru, Chile, Paraguay, Argentina, S+SE Brazil, Uruguay; Helosciadium 1 of 4 Eurasian & African spp intro N+C Chile, NE Argentina; Heracleum  1 of 83 mostly Eurasian spp intro Haiti, S Argentina; Homalocarpus 6 of 6 narrow endemic spp of N+C Chile; Klotzschia 3 of 3 spp endemic C+E Brazil; Lilaeopsis 6 of 13 Americas & Australasia spp native Cuba, Dominican REpublic, Colombia, Ecuador, Peru, Bolivia, Paraguay, S+SE Brazil, Chile, Argentina, Uruguay, inc 1 narrow endemic of S Brazil; Myrrhidendron 5 of 5 Neo endemic spp native Guatemala, Honduras, Costa Rica, Panama, N Andes of Colombia & Ecuador, inc 4 narrow endemics of Colombia (1), Colombia + Ecuador (1), Costa RIca + Panama (1), Panama (1); Neonelsonia monospecific Neo endemic native S Mexico, Guatemala, Andes of SAM in Colombia, Venezuela, Ecuador, Peru; Niphogeton 18 of 18 Neo endemic spp Costa Rica, Panama, N Andes of Colombia, Venezuela, Ecuador, Peru, Bolivia; Notiosciadium monospecific narrow E SAM endemic NE Argentina, Uruguay; Oenanthe ?? of 33 mostly N temperate spp intro Uruguay, NE Argentina; Oligocladus monospecific Argentina endemic NW +S Argentina; Osmorhiza 4 of 12 mostly Americas spp native Guatemala, Colombia, Peru, Bolivia, Argentina, C+S Chile, 1 sp in genus endemic to temperate Asia; Ottoa monospecific N Neo endemic sp native Guatemala, Costa Rica, Colombia, Venezuela, Ecuador; Paraselinum monospecific endemic of Peru, Bolivia; Pastinaca 1 of 15 Eurasian spp, P. sativa (parsnip), intro Greater Antilles, Ecuador, Peru, Bolivia, Argentina, C+S Chile, Uruguay; Pedinopetalum monospecific endemic Dominican Republic; Perissocoeleum  4 of 4 spp endemic Colombia & Venezuela; Petroselinum monospecific Mediterranean sp intro Guatemala, El Salvador, Hispaniola, Puerto Rico, Ecuador, Peru, S Brazil, NE+S Argentina; Pimpinella ?? of 152 Old World spp intro Guatemala, Venezuela, N Argentina, S Brazil; Prionosciadium 1 of 21 Mexico & Guatemala endemic spp native Guatemala; Ptilimnium 1 of 5 USA & Caribbean endemic spp native Cuba,  Hispaniola, Puerto Rico; Rhodosciadium 1 of 15 Mexico & Guatemala endemic spp native Guatemala; Ridolfia monospecific Mediterranean sp intro Peru; Scandix 1  of 12 Mediterranean & C Asia spp intro C Chile, NE Argentina; Seseli 1 of 144 mostly Eurasian spp intro C Chile; Sium 1 of 10 N temperate spp intro N+C Chile; Spananthe 2 of 2 Mexico & Neo endemic spp native CAM (exc Costa Rica), Colombia, Venezuela, Ecuador, Peru, Bolivia, C +E Brazil, Haiti, Trinidad-Tobago, inc 1 narrow endemic of Peru; Spermolepis 1 of 11 Americas endemic spp endemic throughout Argentina; Tauschia 34 of 34 Americas endemic spp native from W USA, Mexico, Guatemala, Colombia, Venezuela, Ecuador; Tiedemannia 2 of 2 S USA & Caribbean endemic spp native Bahamas, Cuba; Tordylium 1 of 20 Mediterranean spp intro NE Argentina;  Torilis ?? of 14 Old World spp intro Peru, Bolivia, C Chile, N Argentina, S Brazil, Uruguay; Visnaga 1 of 2 Mediterranean spp intro Colombia, Peru, C Chile, N Argentina, Uruguay, S Brazil. Azorelloideae: Asteriscium 9 of 9 SAM endemic spp of Chile, Argentina, inc 6 narrow endemics of NW Argentina (3), N Chile (1), C Chile (1), N+C Chile (1); Azorella 20-46 of 53 SAM + Australasia spp native Costa Rica, Colombia & Venezuela along W SAM Andes S through Ecuador, Perú Bolivia, Chile, Argentina S to Patagonia; Bowlesia 16 of 16 former Americas endemic spp native French Guiana, Ecuador, Peru, Bolivia, Paraguay, Chile, Argentina, Uruguay, S+SE Brazil, inc 7 narrow endemics of Argentina (3), Chile (3), Peru (1), 1 sp now intro France, Pakistan; Diposis 3 of 3 S SAM endemic spp each narrow endemics of C Chile (1), S Argentina (1), Uruguay (1); Domeykoa 5 of 5 narrow endemic spp of Peru, N Chile; Eremocharis 9 of 9 narrow W SAM endemic spp of N Chile, Peru; Gymnophyton 6 of 6 spp endemic to the Andes of Chile, Bolivia, NW Argentina, inc 5 narrow endemics of N+C Chile; Pozoa  2 of 2 spp endemic NW+S Argentina, C+S Chile; Mackinlayoideae: Centella ?? of 50 mostly S Africa & pantropical spp native CAM (exc Panama), Bahamas, Turks-Caicos, Greater Antilles, Leeward & Windward Is, Trinidad-Tobago, Juan Fernandez Is, Galápagos Colombia, Venezuela, C+S+E Brazil, Bolivia, Paraguay, C+S Chile, N Argentina, Uruguay; Micropleura 2 of 2 Mexico & Neo endemic spp native Guatemala, El Salvador, Honduras, Costa Rica, Colombia, inc 1 narrow endemic Colombia; Saniculoideae: Eryngium ?? of 247 subcosmopolitan spp native CAM, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Trinidad-Tobago, all of SAM; Sanicula ?? of 47 cosmopolitan spp native CAM (exc Belize), Colombia, Venezuela, Ecuador, Peru, Bolivia, C+S Chile, NW+S Argentina.

Patagonia Genera Include:

60% of Azorelloideae are in South America where they form an important component of the southern temperate zones: Apioideae: Ammi 1 of 3 Mediterranean & Azores spp intro S Chile, S Argentina; Anthriscus ?? of 13 mostly Eurasian spp intro Patagonia; Apium 2 of 12 temperate & subtropical Old World & SAM spp native throughout Patagonia & Falkland Is; Chaerophyllum ?? of 69 mostly N temperate spp native S Chile, S Argentina, Falkland Is; Conium 1 of 6 mostly Eurasian spp intro throughout Patagonia inc Falkland Is; Coriandrum 1 of 2 Middle East spp intro S Argentina; Cyclospermum 1 of 3 former Mexico & Neo endemic spp native throughout Patagonia; Daucus 1-2 of 43 cosmopolitan spp native throughout Patagonia; Foeniculum 1 of 3 Mediterranean spp intro throughout Patagonia; Helosciadium 1 of 4 Eurasian & African spp intro S Argentina;Heracleum  1 of 83 mostly Eurasian spp intro S Argentina; Homalocarpus 1-2 of 6 narrow endemic spp of N+C Chile found near N limit of Patagonia in SC Chile; Levisticum monospecific Middle Eastern sp intro intro S Chile; Lilaeopsis 1 of 13 Americas & Australasia spp native Patagonia & Falkland Is; Oligocladus monospecific Argentina endemic of NW+S Argentina; Osmorhiza 3 of 12 mostly Americas spp native throughout Patagonia; Pastinaca 1 of 15 Eurasian spp intro all Patagonia; Petroselinum monospecific Mediterranean sp (parsley) intro S Argentina;Spermolepis 1 of 11 Americas endemic spp endemic all of Argentina, inc Patagonia. Azorelloideae: Asteriscium 3-4of 9 SAM endemic spp found throughout Patagonia; Azorella ?? of 53 SAM + Australasia spp native throughout Patagonia & Falkland Is;Bolax 2 of 2 Patagonian endemic spp of S Chile, S Argentina, Falkland Is; Bowlesia 4 of 16 former Americas endemic spp native throughout Patagonia, now intro France, Pakistan; Diposis 3 of 3 S SAM endemic spp each narrow endemics of C Chile (1), S Argentina (1), Uruguay (1); Huanaca 2 of 2 Patagonia endemic spp of S Argentina, SC+S Chile; Pozoa  2 of 2 spp endemic S Argentina, C+S Chile. Mackinlayoideae: Centella 1 of 50 mostly S Africa & pantropical spp native C+S Chile. Saniculoideae: Eryngium ?? of 247 subcosmopolitan spp native throughout Patagonia;Sanicula ?? of 47 cosmopolitan 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 definitions from them there.
  • Willis, Lyrae (2022).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this. Orchids, Poaceae, and Cyperaceae have additional references.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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.
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

29 Mar, 2023

9 Oct, 2022

How to Identify the Apocynaceae Dogbane and Milkweed Family

Asclepias variegata Redring Milkweed from Georgia, USA. The Asclepiadaceae or Milkweed family used to be their own family but are now a subfamily of Apocynaceae
Asclepias variegata Redring Milkweed from Georgia, USA. The Asclepiadaceae or Milkweed family used to be their own family but are now a subfamily of Apocynaceae

Table of contents

Introduction to the Apocynaceae Family

The Apocynaceae family is a family of often showy, beautiful flowers that are frequently fragrant but also often happen to be highly poisonous if ingested. The name Dogbane comes from this toxic nature that has poisoned livestock and possibly dogs too. The Apocynaceae was recently revised to include the former Asclepiadaceae or Milkweed Family. There is an excellent reason to do so based on molecular phylogenetics, and the two families are very similar in their morphology and other properties. There are a few notable differences in the Asclepiadoideae subfamily that I have included in detail in the descriptions below.   

Flowers of the Apocynaceae Family

Plants are hermaphrodites; pollination is entomophilous and often conspicuously specialized with trapping mechanisms using modified stylar heads or specialized anthers. Flowers are terminal or axillary and either solitary or aggregated in panicles, cymose (often umbelliform), or rarely in racemose inflorescences. The flowers are often large and showy and are usually bracteate and bracteolate. They are regular, 4-5 merous, tetracyclic, and may be malodorous, fragrant, or odorless. A hypogynous disk is usually present except in the Asclepiadoideae, where it is always absent. The perianth has ten parts in two whorls with a distinct calyx and corolla, which is isomerous. The calyx has five parts in one whorl, is usually connate (at least basally), is regular, and quincuncial (Apocynoideae), imbricate (Asclepiadoideae), or valvular (Asclepiadoideae). The corolla also has five parts in one whorl and may or may not be appendiculate. The corolla is connate with the lobes shorter to longer than the tube. It is usually contorted or rarely valvate, is funnel-shaped or salverform, regular, and comes in various shades of white, yellow, red, orange, pink, purple, or blue.

Androecium of the Apocynaceae Family

The androecium has five members that are adnate and inserted near the base (always Asclepiadoideae), midway down, or in the throat of the corolla tube. They are usually united with the gynoecium (most Apocynoideae) and may form a gynostegium (always in Asclepiadoideae), or they are free of the gynoecium (most Plumerieae, Periplocoideae). They are free of one another or coherent (always one adelphous in Asclepiadoideae) and are one whorled and consist of exclusively fertile stamens. The stamens are isomerous with the perianth and alternate with the corolla members. The anthers are filantherous to sessile and may or may not be appendiculate. In the Asclepiadoideae, the filaments are almost always appendiculate, with their short filaments ornamented from their bases with nectaries. They are separate, cohering, or connivent (often sagittate in Apocynoideae and distinct from one another but attached adaxially to the stylar head in Asclepiadoideae). The anthers are basifixed or adnate, non-versatile, tetrasporangiate, introrse, and usually bilocular and bisporangiate. In Asclepiadoideae, the anthers are appendaged with horny wings and membranous connective appendages contributing to the coronal complex.  

Gynoecium of the Apocynaceae Family

The gynoecium almost always has two carpels but occasionally may have 2–5(6–8) (especially Pleiocarpa). Sometimes the ovary is interpreted as two locular when it is actually the separate ovaries of a syncarpous gynoecium. The pistil has 1–2 cells. The gynoecium is synstylovarious to syncarpous or synstylous (Asclepiadoideae, Plumerieae, Pleiocarpa) and is often superior, otherwise partly inferior. When synstylous the carpel has 2–50 ovules. Placentation when synstylous is marginal. The gynoecium is usually transverse but always median in Asclepiadoideae. There is usually one style but always two in Asclepiadoideae that are partially joined (free below) by the dilated style head with lateral stigmatic surfaces that alternate with the stamens. There is one stigma that is usually massively expanded and may be contracted in the middle with a ring of hairs or a membrane below. Stigmas are wet or dry type, papillate or not, and either Group II, III, or IV type. Placentation when unilocular with two placentas is parietal and when bilocular (mostly) axile or apical. When bilocular (usually), there are 5–50(1-4) ovules per locule, and when unilocular or incompletely bilocular, there are 2–100. Ovules are pendulous, anatropous, unitegmic, tenuinucellate (Apocynoideae) or pseudocrassinucellate (Asclepiadoideae).

Fruit of the Apocynaceae Family

The fruit is often a fleshy or non-fleshy dehiscent capsule or schizocarp with two mericarps of follicles, berrylets, nutlets, or drupelets. Sometimes it is a fleshy indehiscent berry or a drupe. In Asclepiadoideae, it is always a pair of follicles with thin papery placental flaps or may be a single follicle by abortion of the other carpel.  Seeds are oily and may or may not be endospermic or not. They are usually flat and conspicuously hairy (comose in Apocynoideae, Asclepiadoideae) or not and may be winged or wingless.

Habit & Leaf Form of the Apocynaceae Family

The Apoycnaceae are mostly annual or perennial shrubs, lianas, or herbs but sometimes are trees and those trees may have buttress roots (a few in Tabernaemontana, Dyera). All forms are laticiferous, containing a milky latex characteristic of the family. They are self-supporting or climbing stem twiners, root climbers, or scrambling; when twining, they usually twine anticlockwise. Some plants may be switch plants with succulent photosynthetic stems. Others have peculiar vegetative forms like the leaves modified as passive pitcher traps in Dischidia rafflesiana. Leaves are usually well-developed but may be very reduced. They are persistent and simple. Leaves are herbaceous, leathery, membranous, or rarely modified into spines. They may be attached alternate, opposite, whorled three per whorl, or rarely spiral. The leaf lamina is entire and is frequently pinnately veined but may also be one-veined or pinnately to palmately veined. Leaves are usually exstipulate but may be stipulate and sometimes are reduced to colleters found in the stipular position. Domatia occur in 18 genera as pits, pockets, or hair tufts. The leaf lamina is usually dorsiventral, sometimes bifacial, or isobilateral in Nerium oleander. The epidermis sometimes contains crystal idioblasts.  Diverse forms of hairs are often found, and they may be eglandular or glandular, often with glandular shaggy hairs at the lamina bases and on the petiole. Complex hairs are usually not present (except for Pachypodium).

Uses of Apocynaceae 

Most parts of many members of this 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 medicines and rubber.  Many ornamentals come from this family, including Oleander, Frangipani, Carissa, Plumeria, etc. The Asclepiadoideae are an important source of cultivated succulents or vines from Asclepias, Hoya, Araujia, Ceropegia, Stapelia, Caralluma, Decabelone, etc.  Asclepias spp are required for reproduction and food by the famous Monarch Butterfly. Carissa carandas is the source of the edible Natal Plum.  

Morphology of Apocynaceae in North America

Flowers of Apocynum androsaemifolium showing their bell shaped flowers that are common in the Apocynoideae subfamily of the Apocynaceae
Flowers of Apocynum androsaemifolium showing their bell shaped flowers that are common in the Apocynoideae subfamily of the Apocynaceae
Flowers of Asclepias syriaca show the structure of the Asclepiadoideae subfamily of Apocynaceae with their gynostegium & anthers united with the stylar head.
Flowers of Asclepias syriaca show the structure of the Asclepiadoideae subfamily of Apocynaceae with their gynostegium & anthers united with the stylar head.
Flowers of Asclepias variegata showing the umbelliform cyme inflorescence common among the Apocynaceae family
Flowers of Asclepias variegata showing the umbelliform cyme inflorescence common among the Apocynaceae family
Flowers of Nerium oleander showing the 5 part corolla with extra appendages, seen in some members of the Apocynaceae. The pinwheel shape is also common.
Flowers of Nerium oleander showing the 5 part corolla with extra appendages, seen in some members of the Apocynaceae. The pinwheel shape is also common.
Fuzzy follicles of Asclepias syriaca are a bit unique. While follicles are common in the Apocynaceae they tend to be smooth for the most part.
Fuzzy follicles of Asclepias syriaca are a bit unique. While follicles are common in the Apocynaceae they tend to be smooth for the most part.
Drupe of Cascabela ovata. Drupes are less common among the Apocynaceae but are seen in the Apocynoideae and Rauvolfioideae subfamilies.
Drupe of Cascabela ovata. Drupes are less common among the Apocynaceae but are seen in the Apocynoideae and Rauvolfioideae subfamilies.
Dehisced follicle of Asclepias engelmanniana showing the white comose seeds common among many of the Apocynaceae family.
Dehisced follicle of Asclepias engelmanniana showing the white comose seeds common among many of the Apocynaceae family.
Broken follicle of Plumeria rubra showing the milky white latex seen in all members of the Apocynaceae family where it may be seen in fruits, leaves & stems
Broken follicle of Plumeria rubra showing the milky white latex seen in all members of the Apocynaceae family where it may be seen in fruits, leaves & stems
Herbaceous habit of Asclepias latifolia is not the most common habit of the Apocynaceae but there are many well-known herbs, particularly in the Asclepias
Herbaceous habit of Asclepias latifolia is not the most common habit of the Apocynaceae but there are many well-known herbs, particularly in the Asclepias
Cactoid like succulent stem of Pachypodium rutenbergianum - succulent stems are not common but also not rare among the Apocynaceae
Cactoid like succulent stem of Pachypodium rutenbergianum – succulent stems are not common but also not rare among the Apocynaceae
Habit & leaves of Raucolfia tetraphylla showing the shrub form common among the Apocynaceae as well as the whorled leaf attachment also frequently seen.
Habit & leaves of Raucolfia tetraphylla showing the shrub form common among the Apocynaceae as well as the whorled leaf attachment also frequently seen.
The leaf of Asclepias syriaca is a typical entire, herbaceous leaf with pinnate venation so often seen among the Apocynaceae family.
The leaf of Asclepias syriaca is a typical simple, entire, herbaceous leaf with pinnate venation so often seen among the Apocynaceae family.
Leaves of Cascabela ovata are are simple, entire, persistent, leathery, & arranged in a whorled pattern on the stem, all common in the Apocynaceae.
Leaves of Cascabela ovata are are simple, entire, persistent, leathery, & arranged in a whorled pattern on the stem, all common in the Apocynaceae.
Leaves of Asclepias verticillata while they look different than the others shown they are simple, entire, and one-veined, all features of Apocynaceae
Leaves of Asclepias verticillata while they look different than the others shown they are simple, entire, and one-veined, all features of Apocynaceae

Species of Apocynaceae I have Covered So Far

Apocynoideae Subfamily

Adenium obesum native to Africa but cultivated elsewhere. Has large swollen stems with a v enlarged caudex; spiral leaves clustered @ tips; tubular pink flowers 4-5 cm wide w 5 petals.

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 caudex. Spiral leaves are clustered at branch tips. It has tubular pink flowers 4 – 5 cm wide with 5 petals.

Apocynum androsaemifolium branching perennial w opposite ~ ovate leaves; mostly terminal cymes of small campanulate usu pinkish flowers. Native throughout NAM.

Apocynum androsaemifolium – Spreading Dogbane

This is a branching herbaceous perennial with opposite and more or less ovate to somewhat elliptical leaves. Flowers are small, campanulate, whitish-pink, and found mostly in terminal cymes. Native throughout North America.

Apocynum cannabinum erect branching perennial w opposite ~ lanceolate to ovate leaves usu w whitish bloom; flowers small greenish to cream usu terminal; stem usu purplish. NAM native.

Apocynum cannabinum – Indian Hemp

Erect, herbaceous branching perennial with usually purplish-green stems and with opposite lanceolate to ovate 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.

Cascabela ovata shrub or tree w spiral ~ leathery leaves; flower large tubular yellow; fruit ~ round light green but turning purplish. Native to Mexico & CAM. Common in Mexico.

Cascabela ovata – Yellow Oleander

A self-supporting perennial shrub or tree with spiral, moderately thick, and leathery leaves with prominent pinnate venation. Flowers are large, showy, tubular, and yellow. The fruit is large and drupaceous with multiple large stony seeds, roughly orbicular light green, becoming purplish when mature. Native and common in Mexico, also Central America.

Nerium oleander cultivated spp originally from Mediterranean; thick leathery lanceolate leaves in whorls of 2-3; flowers deeply 5-lobed w fringed corolla around mouth of tube; fragrant.

Nerium oleander – Oleander or Nerium

This cultivated species is originally from the Mediterranean. It has thick leathery lanceolate leaves in whorls of 2 – 3. Flowers are deeply 5-lobed with a fringed corolla around the mouth of the floral tube; they are very fragrant.

Pachypodium rutenbergianum cultivated succulent tree w thick branches & long spines; leaves long leathery oblong-lanceolate leaves; flowers white w yellow center. Native Madagascar.

Pachypodium rutenbergianum – Madagascar Palm

This is a unique-looking succulent tree 3 – 8 m tall with very thick succulent branches, long spines, and an enlarged caudex. It has long, leathery, oblong–lanceolate leaves. Flowers are white with a yellow center, petals spreading in a pinwheel shape. Native to Madagascar & cultivated elsewhere.

Trachelospermum jasminoides cultivated Asian shrub w ~ elliptic to ovate glabrous leaves; few-flowered cymes on long peduncles; white flowers are v fragrant, hairy inside tube.

Trachelospermum jasminoides – Star Jasmine

This is a vigorous medium-sized evergreen shrub or vine with elliptic to ovate glabrous glossy green leathery leaves. Flowers are in few-flowered cymes on long peduncles; they are very fragrant and pubescent inside the tube. Native to Asia but widely cultivated elsewhere.

Asclepiadoideae Subfamily

Asclepias arenaria has densely woolly leaves & stems, leaves broadly ovate & often undulate; flowers axillary greenish to cream color; endemic to Great Plains region of the USA.

Asclepias arenaria – Western Sand Milkweed

Erect herbaceous perennial with densely woolly leaves and stems. Leaves are broadly ovate and often very undulate on the margins. Flowers are axillary and greenish to cream color. Endemic to the Great Plains region of the USA, very drought-tolerant.

Asclepias asperula long narrow leaves usu fold lengthwise; usu terminal inflorescence w ~green flowers w maroon highlights. Follicles usu curve like a horn. Native SW USA, N Mexico.

Asclepias asperula – Antelope Horns

This is a clump-forming 1 – 2 ft tall perennial with long narrow leaves that are usually folded lengthwise. Flowers are usually in globose terminal inflorescences with greenish flowers with maroon highlights. Follicles usually curve like a horn. Native to southwestern USA, northern Mexico.

Asclepias curassavica perennial native of SAM, intro elsewhere. Flowers w purple or red corollas & yellow or orange coronas; leaves narrow lanceolate w acute/ acuminate tips.

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. Leaves are narrow lanceolate with acute or acuminate tips. 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 1-4 branching stems w long & v narrow leaves grouped in 2-3 in upper plant; pale green flowers in crowded inflorescence upper axils. Endemic Great Plains USA.

Asclepias engelmanniana – Engelmann’s Milkweed

A tall, slender perennial with 1 – 4 branching stems with long and very narrow linear–lanceolate leaves, usually in groups of 2 – 3. Pale green flowers without horns are crowded in umbels in the upper axils. Endemic to the Great Plains of the USA.

Asclepias incarnata branched on upper stem w lanceolate to linear-oblong leaves; corolla pink to red (white), horn incurved surpasses hood. Native swamps/wet areas of east NAM.

Asclepias incarnata – Swamp Milkweed

A herbaceous perennial that is branched on the upper part of the stem and has lanceolate to linear–oblong leaves. Corolla is pink to red (rarely white), and the horn is incurved and surpasses the hood. Native to swamps and other wet areas of eastern North America.

Asclepias latifolia unbranched w v large & broad leaves w prominent veins; flowers pale green to yellow, often hidden in axils by leaves. Native W USA & N Mexico, mostly Great Plains.

Asclepias latifolia – Broadleaf Milkweed

This unbranched 2 – 3 ft tall herbaceous perennial has very large, broad, somewhat obovate to 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 western USA and northern Mexico, mostly in the Great Plains.

Asclepias pumila inflorescence flowers, fruits.

Asclepias pumila – Plains Milkweed

This short herbaceous perennial is usually less than 30 cm tall with narrow leaves that are densely spaced, appearing whorled but, upon close inspection, are condensed alternate. Flowers are light pink or white in terminal inflorescences. Endemic to the Great Plains region of the USA.

Asclepias subverticillata branched or not perennial; v narrow leaves w revolute margins whorls of 3-5; star-like flowers upper axillary umbels. native C+SW USA, N Mexico.

Asclepias subverticillata – Horsetail Milkweed

This erect, spreading, herbaceous perennial may or may not be branched, growing to 1 m tall with sparse narrow linear leaves with revolute margins growing in whorls of 3 – 5 at branch nodes. Star-like whitish or cream flowers grow in the upper axillary umbels. Native to central and southwestern USA and northern Mexico.

Asclepias syriaca tall perennial w large ovate to ~ elliptic leaves abaxial surface lighter green; s/w pendulous axillary umbels; flowers usu pink (white), horns inflexed. Native E USA + Canada.

Asclepias syriaca – Common Milkweed

A tall perennial to 1 m tall with large ovate to somewhat elliptic leaves with pale green on the abaxial surface. Flowers are in somewhat pendulous axillary umbels, usually pink (rarely white), with inflexed horns. Follicle has a very roughly textured surface. Native to the eastern USA and Canada.

Asclepias tuberosa stem s/t branched above, hairy; leaves linear to ~ lanceolate, opp or alt on branches; terminal umbels of yellow to red-orange flowers. Native SE Canada, E+SW USA.

Asclepias tuberosa – Butterfly weed

A bushy herbaceous perennial to 60 cm tall, pubescent stem may be single or branched in the top half. Leaves are linear to more or less lanceolate and may be opposite or alternate on branches. Flowers are in terminal flat-topped umbels of yellow to red-orange flowers. Native to southeastern Canada, eastern and southwestern USA.

Asclepias variegata usu unbranched w several pairs of opp broad oblong to ovate leaves; 1-4 compact umbels w white / pink tinged flowers w divergent hoods. Native E NAM.

Asclepias variegata – Red Ring Milkweed

Herbaceous perennial with usually unbranched stems w several pairs of opposite broadly oblong to ovate leaves. Flowers in 1 – 4 globose compact umbels with showy white and pinkish-red tinged flowers with divergent hoods. Native to eastern North America, rare in the north, most common in the southeastern USA.

Asclepias verticillata branched at top/not w numerous narrow leaves in whorls of 3-6; several umbels in upper axils w white to greenish flowers, s/w divergent hoods, horns > hoods. E NAM

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 divergent hoods and horns that are larger than the hoods. Native to eastern North America and parts of western North America.

Cyanchum laeve climbing vine sparsely hairy w opp cordate leaves w axillary umbellate cymes of 5-40 flowers; fruit ovate or tear shaped follicle. Native C+E USA, SE Canada

Cyanchum laeve – Climbing Milkweed or Sand Vine

This is a climbing vine that is sparsely hairy with opposite cordate leaves with palmate venation. Flowers are in axillary umbellate cymes of 5 – 40 flowers. Fruit is an ovate follicle. Native to central and eastern USA, southeastern Canada

Funastrum clausum tendril climbing vine; linear to oblong leaves are pubescent & ~ succulent; axillary flowers w pubescent white petals. Native S USA, Mexico & tropical Americas

Funastrum clausum – White Twinevine

A tendril-climbing perennial vine with linear to oblong leaves that are pubescent and somewhat succulent. Axillary flowers have pubescent white petals. Native to the southern USA, Mexico, and the tropical Americas.

Marsdenia edulis twining vine w leathery light green leaves; whitish flowers in axillary umbels; fruit a large ~ovate follicle edible when young. Native to Mexico.

Marsdenia edulis – Talayote or Tonchi

Twining vine with leathery glossy light green leaves with glaucous lower surfaces. Whitish flowers are in axillary umbels. Fruit is a large, somewhat ovate follicle that is edible when young. Native to Mexico.

Rauvolfioideae Subfamily

Carissa macrocarpa leathery, glossy dark green leaves, v fragrant white flowers, large reddish drupes are edible (Natal Plum). Native Africa, cultivated in S NAM and tropical Americas

Carissa macrocarpa – Natal Plum

Spiny evergreen shrub with leathery, glossy dark green leaves. Flowers are very fragrant and white with long narrow petals. Fruit is a large, reddish, edible drupe. Native to Africa, cultivated in southern North America and tropical Americas

Catharanthus roseus evergreen subshrub w glabrous ovate leaves in opp pairs; flowers white w yellow/red center or dark pink w red center. Native Madagascar cultivated in NAM

Catharanthus roseus – Madagascar Periwinkle

An evergreen subshrub with glabrous ovate leaves 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 shrub/ small tree w succulent trunk & branches; large deciduous leaves clustered at branch ends; flowers terminal white to pink v fragrant. Native Mexico & tropical Americas.

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 Americas, widely cultivated elsewhere.

Rauvolfia tetraphylla much-branched shrub to small tree w 4(3-5) whorled leaves per node; flowers axillary small white, fruit is a red 2-seeded drupe. Native Mexico & tropical Americas.

Rauvolfia tetraphylla – Devil Pepper

A much-branched shrub to small tree with 4 (3 – 5) whorled obovate, elliptic, or ~ oblong leaves per node. Flowers are small and white in axillary clusters. The fruit is a small red 2-seeded drupe. Native to Mexico and tropical Americas.

Vinca major – Greater Periwinkle

A scrambling vine with opposite semi-evergreen leaves with a waxy cuticle and tiny hairs, sometimes with ciliate margins. Flowers are pink to violet, partially connate, and pinwheel-like. Native to the western Meditteranean, widely cultivated as a groundcover, and highly invasive in some areas.

Vinca minor – Periwinkle

A scrambling vine with opposite glabrous evergreen leaves that are smaller and narrower than V. major and never have a ciliate margin. Flowers are similar to V. major but a little smaller. Native to Eurasia, widely cultivated and highly invasive in some areas.

Taxonomy of Apocynaceae

The Apocynaceae contains roughly 5000 spp in about 400 genera contained within five subfamilies. It is part of the Gentianales order of the core Eudicots. Asclepiadoideae was recently included in Apocynaceae, greatly increasing the number of species and genera. As with most families, thanks to molecular phylogenetics clarifying our understanding of the plant families, the genera and species have been undergoing revisions. Once major updates have been made, I will also update the lists here.

  1. Apocynoideae is a diverse subfamily of annual or perennial herbs, shrubs, lianas, and the occasional tree. They exude milky latex, but it is sometimes clear. Leaves are simple and entire but otherwise variable. They usually are exstipulate or have very small stipules. The stamen are almost always usually united with the gynoecium but do not form a true gynostegium, they also lack pollinaria. 
  2. Asclepiadoideae is a subfamily that can usually be easily recognized by the presence of a gynostegium with its one adelphous stamens and two styles that are partially joined (free below) by the dilated style head with lateral stigmatic surfaces that alternate with the stamens. There is no hypogynous disk, and the gynoecium is also always median, both of these characteristics are unlike the rest of the family. The fruit is always a follicle (1-2). 
  3. Periplocoideae is a family of herbs, shrubs, vines, or rarely small trees. Colleters are present in the sinuses of the calyx. The stamens are free of the gynoecium (unlike most of the family, excluding Plumerieae in Rauvolfioideae), but the triangular anthers are adnate to the style head.  
  4. Rauvolfioideae is split into eleven diverse tribes. In general, they are mostly trees and shrubs with some herbs or lianas. They also have variable fruit and floral morphology. Sometimes the stamens are free of the gynoecium (unlike most of the family except Periplocoideae). 
  5. Secamonoideae is a small subfamily of lianas or vines that climb by twining, or rarely they may be shrubs. Sometimes there are colleters on the adaxial leaf surface. 

Genera:

Apocynoideae: Adenium (6), Aganosma (9), Alafia (26), Allomarkgrafia (10), Allowoodsonia (1), Amalocalyx (1), Angadenia (2), Anodendron (17), Apocynum (4), Artia (5), Asketanthera (4), Baharuia (1), Bahiella (2), Baissea (18), Beaumontia (9), Carruthersia (4), Cascabela (6), Chonemorpha (10), Cleghornia (2), Cycladenia (1), Dewevrella (1), Echites (14 inc Fernaldia), Ecua (1), Elytropus (1), Ephippiocarpa (2), Epigynum (5 inc Nouettea), Eucorymbia (1), Farquharia (1), Forsteronia (41), Funtumia (2), Galactophora (6), Holarrhena (5), Hylaea (2), Ichnocarpus (3), Isonema (3), Ixodonerium (1), Kibatalia (15), Laubertia (4), Macropharynx (15 inc Peltastes), Malouetia (31), Mandevilla (177 inc Dipladenia, Macrosiphonia, Quiotania, Salpinctes), Mascarenhasia (8), Mesechites (8), Micrechites (13 inc Vallariopsis), Motandra (3), Neobracea (8), Nerium (1), Odontadenia (21), Oncinotis (7), Pachypodium (22), Pacouria (3), Papuechites (1), Parepigynum (1), Parsonsia (85 inc Delphyodon, Grisseea, Lyonsia), Pentalinon (2), Pinochia (4), Pleioceras (5), Pottsia (3), Prestonia (65 inc Rhodocalyx), Rhabdadenia (3), Rhazya (2), Secondatia (5), Sindechites (1), Spirolobium (1), Stephanostema (1), Stipecoma (1), Streptoechites (1), Strophanthus (39), Temnadenia (3), Thenardia (3), Thoreauea (3), Thyrsanthella (1), Tintinnabularia (3), Trachelospermum (9), Urceola (21 inc Aganonerion, Ecdysanthera, Hymenolophus, Parameria, Xylinabaria, Xylinabariopsis), Vallaris (3), Wrightia (34). 

Asclepiadoideae: Ampelamus (3), Amphineurion (1), Anemotrochus (3), Anisopus (2), Anisotoma (3), Apteranthes (7), Araujia (13 inc Hickenia, Morrenia, Stuckertia), Asclepias (206 inc Aidomene, Odontostelma), Aspidoglossum (37), Aspidonepsis (5), Astephanus (2), Asterostemma (1), Australluma (1), Ballyanthus (2), Barjonia (7), Baynesia (1), Blepharodon (26 inc Anomotassa), Boucerosia (7 inc Frerea), Calciphila (2), Calotropis (3), Campestigma (1), Caralluma (31), Caudanthera (4), Ceropegia (411 inc Brachystelma, Macropetalum, Tenaris), Chlorocyathus (2), Cibirhiza (3), Cionura (1), Conomitra (1), Cordylogyne (2), Cosmostigma (3), Cristobalia (2), Cynanchum (256 inc Adelostemma, Decanemopsis, Dicarpophora, Drepanostemma, Folotsia, Glossonema, Graphistemma, Holostemma, Karimbolea, Mahafalia, Metaplexis, Nematostemma, Odontanthera, Pentarrhinum, Platykeleba, Prosopostelma, Pycnoneurum, Raphistemma, Sarcostemma, Seshagiria, Telminostelma, Voharanga, Vohemaria), Decanema (1), Desmidorchis (14), Diplolepis (14), Dischidanthus (1), Dischidia (118 inc Dolichostegia, Hoyella), Ditassa (112), Dolichopetalum (1), Dregea (7), Duvalia (18), Duvaliandra (1), Echidnopsis (36), Edithcolea (1), Emicocarpus (1), Emplectanthus (3), Eustegia (5), Fanninia (1), Fischeria (8), Fockea (6), Funastrum (21), Glossostelma (12), Gomphocarpus (20), Gongronema (9), Gonolobus (119 inc Microstelma), Gunnessia (1), Gymnema (34 inc Bidaria), Gyrostelma (1), Hemipogon (8), Heterostemma (45 inc Dittoceras), Heynella (1), Hiepia (1), Hoodia (13 inc Trichocaulon), Hoya (534 inc Absolmsia, Anatropanthus, Clemensiella), Huernia (77), Hypolobus (1), Ibatia (26), Jasminanthes (13), Jobinia (25 inc Cyathostelma), Kanahia (2), Kerbera (1), Lachnostoma (11), Larryleachia (6), Lavrania (1), Leptadenia (5), Lygisma (5 inc Costantina), Macroscepis (16), Mahawoa (1), Manothrix (2), Margaretta (1), Marsdenia (305 inc Dalzielia, Gymnemopsis, Harmandiella, Leichardtia, Papuastelma, Thozetia), Matelea (271 inc Dictyanthus, Jacaima, Labidostelma, Lhotzkyella, Microdactylon, Prosthecidiscus, Tetracustelma, Trichosacme), Metastelma (100 inc Meresaldia), Microloma (11), Minaria (22), Miraglossum (7), Monolluma (5), Monsanima (2), Morilloa (4), Nautonia (1), Neoschumannia (3 inc Swynnertonia), Nephradenia (5), Notechidnopsis (1), Oistonema (1), Oncinema (1), Ophionella (2), Orbea (60 inc Orbeanthus, Orbeopsis, Pachycymbium), Oreosparte (1), Orthanthera (6), Orthosia (38), Oxypetalum (135 inc Amblyopetalum, Corollonema, Dactylostelma, Rhyssostelma, Schistogyne, Widgrenia), Oxystelma (2), Pachycarpus (39), Parapodium (3), Pattalias (2), Pectinaria (5), Pentacyphus (3 inc Tetraphysa), Pentasacme (4), Pentatropis (4 inc Strobopetalum), Peplonia (9 inc Gonioanthela, Macroditassa), Pergularia (2), Periglossum (3), Petalostelma (7 inc Lagoa), Phaeostemma (7), Pherotrichis (4), Philibertia (41 inc Amblystigma, Lugonia, Melinia, Mitostigma, Podandra, Steleostemma, Stelmatocodon), Piaranthus (9 inc Huerniopsis), Polystemma (5), Pruskortizia (2), Pseudolachnostoma (8), Pseudolithos (8), Ptycanthera (2), Pycnorhachis (1), Quaqua (20), Rhyssolobium (1), Rhytidocaulon (17), Rhytidostemma (8),Richtersveldia (1),  Riocreuxia (10), Rojasia  (2), Ruehssia (42), Sarcolobus (20 inc Dorystephania, Quisumbingia), Schistonema  (1), Schizoglossum (26), Schizostephanus  (2), Schubertia (6), Scyphostelma (28), Sisyranthus (13), Socotrella (1), Solenostemma (1), Stapelia (31), Stapelianthus (7), Stapeliopsis (8), Stathmostelma (14), Stelmagonum (1), Stenostelma (6), Stephanotis (4), Stigmatorhynchus (2), Tassadia (31 inc Stenomeria), Tavaresia (3 inc Decabelone), Telosma (9), Topea (2), Toxocarpus (33), Tressensia (1), Treutlera (1), Tridentea (8), Tromotriche (11), Tweedia (6), Tylodontia (4), Vailia (1), Vincetoxicum (248 inc Belostemma, Biondia, Blyttia, Diplostigma, Ischnostemma, Merrillanthus, Oncostemma, Pentabothra, Pentastelma, Podostelma, Rhyncharrhena, Sphaerocodon, Spirella, Tylophora, Tylophoropsis, Vincetoxicopsis), Wattakaka (2), White-Sloanea (1), Woodia (3), Xysmalobium (42).

Periplocoideae: Atherandra (1), Baroniella (10), Baseonema (1), Batesanthus (3), Buckollia (2), Camptocarpus (9), Cryptolepis (42), Cryptostegia (2), Decalepis (5 inc Janakia), Ectadium (2), Epistemma (4), Finlaysonia (6), Gymnanthera (2), Hemidesmus (1), Ischnolepis (2 inc Petopentia), Maclaudia (1), Mondia (2), Myriopteron (1), Pentopetia (23), Periploca (17), Phyllanthera (10 Australasia); Raphionacme (36), Sacleuxia (2), Sarcorrhiza (1), Schlechterella (2 inc Pleurostelma); Stomatostemma (1), Streptocaulon (5); Tacazzea (5), Telectadium (3), Zygostelma (1). 

Rauvolfioideae: Acokanthera (5), Allamanda (15), Alstonia (44), Alyxia (106), Ambelania (3), Amsonia (16), Ancylobothrys (7), Anechites (1), Aspidosperma (77), Bousigonia (3), Callichilia (6), Calocrater (1), Cameraria (7), Carissa (9), Carvalhoa (2), Catharanthus (9),  Cerbera (6), Cerberiopsis (3), Chamaeclitandra (1), Chilocarpus (14), Clitandra (1), Condylocarpon (7), Couma (5), Craspidospermum (1), Crioceras (1), Cyclocotyla (1), Cylindropsis (1), Dictyophleba (6), Diplorhynchus (1), Dyera (2), Geissospermum (5),  Gonioma (2), Hancornia (1), Haplophyton (2), Himatanthus (9), Hunteria (12), Kamettia (2), Kopsia (24), Lacmellea (24), Landolphia (63 inc Carpodinus), Laxoplumeria (5), Lepinia (4), Lepiniopsis (2), Leuconotis (4), Macoubea (3), Melodinus (24), Microplumeria (1), Molongum (3), Mortoniella (1), Mucoa (2), Neocouma (2), Ochrosia (44), Orthopichonia (6), Parahancornia (7), Petchia (8 inc Cabucala), Picralima (1), Plectaneia (3), Pleiocarpa (6), Plumeria (19), Pteralyxia (2), Pycnobotrya (1), Rauvolfia (74), Rhigospira (1), Saba (3), Schizozygia (1), Skytanthus (3), Spongiosperma (6), Stephanostegia (2), Strempeliopsis (2), Tabernaemontana (123 inc Stemmadenia, Woytkowskia), Tabernanthe (2), Thevetia (3), Vahadenia (2), Vallesia (11), Vinca (7); Voacanga (13), Willughbeia (16 inc Urnularia),

Secamonoideae: Calyptranthera (13), Genianthus (17), Goniostemma (2), Pervillaea (5), Secamone (~ 100 inc Rhynchostigma), Secamonopsis (2), Toxocarpus (33), Trichosandra (1).

Distribution of Apocynaceae

The Apocynaceae are mostly subtropical to tropical with a few temperate representatives.  They are cosmopolitan in distribution, and they are widely found throughout the entire Americas, including some herbaceous forms found up into Arctic Canada. 

Distribution of Apocynaceae in the Americas

Canadian Genera Include:

Apocynoideae: Apocynum 2 of 4 N temperate spp native in almost all of Canada inc Arctic but exc NU and Labrador, 1 NAM hybrid sp also native in this range.

Asclepiadoideae: Asclepias 15 of 206 Americas & Africa spp native in all S provinces but intro in NL (exc Labrador); Cynanchum 1 of 256 subcosmopolitan spp intro ON; Vincetoxicum 3 of 248 Old World spp intro BC, ON, QC, NB. Rauvolfioideae: Vinca 2 of 7 Mediterranean spp intro BC, ON, QC, NS and NB.

USA Genera Include:

Apocynoideae: Angadenia 1 of 2 Caribbean & SE USA endemic spp native FL, NC; Apocynum 2 of 4 N temperate spp native all of USA inc AK, plus 1 NAM hybrid sp native in this range;  Beaumontia 1 of 9 SE Asia spp intro HI?; Cycladenia monospecific SW USA endemic CA, AZ, UT; Echites 1 of 14 NAM, CAM & Caribbean spp native FL; Mandevilla 4 of 177 former Americas endemic spp native AZ, NM, TX; Nerium monospecific Mediterranean sp intro most of S border states exc NM, also UT, CA; Pentalinon 1 of 2 Mexico, CAM & Caribbean endemic spp native S FL; Rhabdadenia 1 of 3 S NAM & Neo endemic spp native FL; Thyrsanthella monospecific SE USA endemic of OK, TX, MO, AR, LA, IL, IN, KY, TN, MS, AL, GA, FL, SC, NC, VA, DE; Trachelospermum 2 of 9 mostly S+E Asia spp inc 1 sp native and 1 sp intro TX, OK, MO, AR, LA, MS, AL, GA, FL, SC, NC, VA, MD, DE, TN, KY, IL, IN. 

Asclepiadoideae:  Ampelamus 2 of 3 Americas endemic spp native SE USA from NE S to TX and E to PA, S to FL plus ID, AZ, NY; Araujia (inc Morrenia) 2 of 13 former Neo endemic spp intro CA, GA, FL; Asclepias 75 of 206 Americas & Africa spp native (everywhere) and intro (some states) all of USA and native HI; Calotropis 2 of 3 Old World Tropics spp intro CA, FL and HI; Cynanchum 17 of 256 subcosmopolitan spp native and intro most of USA exc WA, OR, WY, MT, CO, ND, SD, inc 1 sp formerly known as Metaplexis intro IA; Funastrum 5-7 of 21 former Americas endemic spp native CA, NV, UT, CO, AZ, NM, TX, OK, AR, FL, now intro India; Gomphocarpus 1 of 20 African & Arabian spp intro CA?; Gonolobus ? of 119 former Americas endemic spp native AZ, KS, OK, TX, MO, AR, LA, IL, IN, KY, TN, MS, AL, GA, FL, NC, SC, VA, MD; Hoya 1 of 54 S Asia & Australasia spp intro HI; Matelea 24 of 271 Americas endemic spp native in all S half of USA from CA E to PA but exc NV, UT, CO; Metastelma ? of 100 Americas endemic spp native AZ, NM, TX, FL; Orthosia ? of 38 Americas endemic spp native MS, FL, GA, SC; Pattalias 1 of 2 S NAM & Caribbean endemic spp native  TX, LA, MS, AL, GA, FL, SC, NC; Polystemma 1 of 5 S NAM + CAM endemic spp native AZ?; Stapelia 1 of 31 S Africa spp intro HI; Vincetoxicum 3 of 248 Old World spp intro CA, NE, KS, MN, MO, MI, WI, IL, IN, KY, OH, PA, NJ, MD, NY, CT, RI, MA, VT, NH, ME.

Periplocoideae: Cryptostegia 2 of 2 Madagascar spp intro TX, FL; Periploca 1 of 17 African spp intro KS, OK, TX, TN, VA, PA, NJ, NY, CT, RI.

Rauvolfioideae:Allamanda 1 of 15 former Neo endemic spp intro FL; Alstonia 1 of 44 pantropical (exc SAM) spp intro FL and HI; Alyxia 1 of 106 SE Asia, Australia & Pacific spp native HI; Amsonia 16 of 16 American & SE Asian spp inc 14 spp native all S USA from CA E to NJ but exc WV and 2 spp intro inc NY, CT, MA, inc 10 endemics to USA, 4 of which are narrow endemics of AZ (2), NM (1), OK + AR (1); Carissa 1 of 9 Old World Tropics spp intro AZ, TX, FL; Catharanthus 1 of 9 Indian & Madagascar spp intro CA, TX, LA, MS, FL, GA, SC, NC, OH and HI; Haplophyton 1 of 2 S NAM & N CAM endemic spp native AZ, NM, TX; Ochrosia 4 of 44 tropical Asia & Pacific spp intro FL, native HI; Plumeria 1 of 19 former Americas endemic spp native FL, now intro SE Asia, Africa; Pteralyxia 2 of 2 spp endemic HI;  Rauvolfia 3 of 74 pantropical spp native FL, intro and native HI; Tabernaemontana 2 of 123 pantropical spp spp native FL, intro HI; Thevetia 1 of 3 former Mexico & Neo endemic spp intro TX, FL, HI?; Vallesia 2 of 11 Americas endemic spp inc 1 sp native and 1 sp intro CA, FL; Vinca 3 of 7 Mediterranean spp intro most of USA exc NV, OK, CO, WY, ND, SD.

Mexico Genera Include:

Apocynoideae: Apocynum 1 of 4 N temperate spp native N Mexico, plus 1 NAM hybrid sp native in this range; Cameraria 1 of 7 spp former Mexico & N Neo endemic spp native SE Mexico, this sp is now intro SE China; Cascabela 5 of 6 former Mexico & Neo endemic spp native all of Mexico inc 3 endemics of Mexico, 1 of which is a narrow endemics of Mch (1), genus now intro pantropical; Echites 7 of 14 NAM, CAM & Caribbean spp native most of Mexico exc BC, BCS, Son, Sin, inc 1 sp endemic to SW+C Mexico; Forsteronia ?? of 41 Neo endemic spp native SW+SE Mexico, Ver, Chp; Laubertia 1 of 4 Mexico & Neo endemic spp endemic most of Mexico exc Ver; Mandevilla ?? of 177 former Americas endemic spp native all of Mexico, genus now intro SE China; Mesechites 1 of 8 Mexico & Neo endemic spp native Mexico exc BC, BCS, Son, Sin, Mex, Cd Mex, Pue, Tlx, Mor; Nerium monospecific Mediterranean sp intro most of Mexico exc BC, BCS, Son, Sin, Ver; Odontadenia 1 of 21 Neo endemic spp native SW+SE Mexico, Chp; Pentalinon 1 of 2 Mexico, CAM & Caribbean endemic spp native SW+C+SE Mexico; Pinochia 2 of 4 Mexico & N Neo endemic spp native SW+SE Mexico, Chp, Ver; Prestonia ?? of 65 Mexico & Neo endemic spp native most of Mexico exc BC, BCS, Son, Sin; Rhabdadenia 1 of 3 S NAM & Neo endemic spp native Ver, Cam, Tab, Yuc, QR, Chp; Thenardia 3 of 3 S Mexico & Honduras endemic spp native SW+C+SE Mexico, inc 2 endemics of SW+C Mexico; Thoreauea 3 of 3 spp endemic to SW Mexico + Ver; Tintinnabularia 2 of 3 Mesoamerica endemic spp native Oax, Chp, Ver, inc 1 narrow endemic of Ver.  

Asclepiadoideae: Ampelamus 2 of 3 Americas endemic spp native Mexico exc Ver, Chips, Tab, Cam, Yuc, QR; Asclepias ?? of 206 Americas & Africa spp native all of Mexico; Blepharodon 1 of 26 spp Mexico & Neo endemic native all of Mexico; Calotropis 1 of 3 Old World Tropics spp intro SW+C+SE Mexico;  Cynanchum ?? of 256 subcosmopolitan spp native all of Mexico; Fischeria 1 of 8 Neo endemic spp native SW+C+SE Mexico; Funastrum 13 of 21 former Americas endemic spp native throughout all of Mexico, inc 3 endemic to Mexico, 1 of which is a narrow endemic of BCN + BCS?, 1 sp now intro India;  Gomphocarpus 1 of 20 African & Arabian spp intro SW Mexico;  Gonolobus ?? of 119 former Americas endemic spp native all of Mexico, now intro Africa; Jobinia ?? of 25 Neo endemic spp native Ver; Macroscepis 4 of 16 Mexico & Neo endemic spp native all of Mexico, inc 2 narrow endemics of Chp (1), Yuc (1); Marsdenia ?? of 305 pantropical spp native all of Mexico; Matelea (inc Dictyanthus 16 spp endemic Mexico) 16+ ?? of 271 Neo endemic spp native all of Mexico; Metastelma ?? of 100 Americas endemic spp native all of Mexico inc Mexican Pacific Is; Orthosia ?? of 38 Americas endemic spp native most of Mexico exc BC, BCS, Son, Sin; Oxypetalum ?? of 135 Mexico & Neo endemic spp native NE+SW+SE Mexico, Ver; Pattalias 2 of 2 S NAM & Caribbean endemic spp native all of Mexico, inc 1 narrow endemic of BCN, BCS; Pherotrichis 4 of 4 Mexico & N CAM endemic spp native most of Mexico exc Ver, inc 3 Mexican endemics of N Mexico (1), SW Mexico (1), Jal + Mch (1); Polystemma 5 of 5 S NAM + CAM endemic spp native NW+C+SE Mexico, Ver, inc 2 spp endemic to Mexico, 1 of which is a narrow endemic of Son; Ruehssia ?? of 42 Mexico & Neo endemic spp native NE+SW+SE Mexico, Ver, Chp; Stelmagonum monospecific endemic of SW Mexico; Tassadia ?? of 31 Neo endemic spp native SW+SE Mexico, Ver. 

Periplocoideae: Cryptostegia 2 of 2 Madagascar spp intro W+SE Mexico.

Rauvolfioideae: Allamanda 1 of 15 former Neo endemic spp intro SW+C Mexico; Alstonia ?? of 44 pantropical (exc SAM) spp native SW+C+SE Mexico; Amsonia 4 of 16 mostly Americas spp native to N Mexico; Aspidosperma ?? of 77 Neo endemic spp native SW+SE Mexico, Ver; Carissa 1 of 9 Old World Tropics spp intro SW+C Mexico; Catharanthus 1 of 9 Indian & Madagascar spp intro SW+SE Mexico; Haplophyton 2 of 2 S NAM & N CAM endemic spp native most of Mexico exc Ver; Plumeria 2 of 19 former Americas endemic spp native all of Mexico, now intro SE Asia, Africa; Rauvolfia ?? of 74 pantropical spp native all of Mexico; Tabernaemontana ?? of 123 pantropical spp native all of Mexico; Thevetia 1 of 3 former Mexico & Neo endemic spp native most of Mexico exc BC, BCS, Son, Sin, sp now intro SE China; Vallesia 8 of 11 Americas endemic spp native all of Mexico, inc 5 narrow endemics of Son (1), Sin (1), BC (1), Jal (1), Oax (1); Vinca 1 of 7 Mediterranean spp intro SW+C+SE Mexico.

Neotropical Genera Include:

Apocynoideae:Allomarkgrafia 10 of 10 Neo endemic spp Honduras, Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru; Angadenia 2 of 2 Caribbean & SE USA endemic spp native Bahamas, Turks-Caicos, Cuba, Hispaniola, Jamaica, inc 1 Caribbean endemic; Anodendron 1 of 17 S+E + Tropical Asia spp intro Trinidad-Tobago; Asketanthera 4 of 4 Greater Antilles endemic spp of Cuba, Dominican Republic, Haiti; Bahiella 2 of 2 spp narrow endemics of NE Brazil; Beaumontia 1 of 9 SE Asia spp intro Costa Rica, Guatemala, El Salvador, Honduras; Cascabela 3 of 6 spp former Mexico & Neo endemic spp native CAM S through tropical SAM to Peru, Bolivia, NE Argentina, SE Brazil (exc NE Brazil), intro Bermuda, Bahamas,  Antilles (exc Cayman Is, Netherlands Antilles), Africa, India, Asia; Echites 13 of 14 NAM, CAM & Caribbean endemic spp of CAM, Bahamas, Turks-Caicos, Greater Antilles, Leeward Is, inc 4 narrow endemics of Cuba (2), Costa Rica (1), Panama (1); Forsteronia 41 of 41 Neo endemic spp native Cuba, Jamaica, Trinidad-Tobago, CAM, tropical SAM S to N Argentina (exc N Chile); Funtumia 1 of 2 African spp intro Cuba, Puerto Rico, Trinidad-Tobago, El Salvador; Galactophora 6 of 6 SAM endemic spp of Colombia, N+C Brazil, Venezuela, Guyana, Peru, Bolivia; Hylaea 2 of 2 N SAM endemic spp of S Venezuela, N Brazil; Laubertia 3 of 4 Neo endemic spp native Belize, Colombia, Venezuela, N Brazil, Ecuador, Peru, Bolivia, inc 2 narrow endemics of Belize (1), N Brazil (1); Macropharynx 15 of 15 Neo endemic spp of Honduras, Costa Rica, Panama,  Colombia, Venezuela, Guyana, Suriname, Ecuador, Peru, Bolivia, Paraguay, Brazil, N Argentina; Malouetia ?? of 31 Neo & W Africa spp native CAM (exc El Salvador), Windward Is, Colombia, Venezuela, French Guiana, Suriname, Guyana, Brazil (exc C Brazil), Peru, Bolivia, intro Cuba; Mandevilla 177 of 177 former Americas endemic spp native S USA, Mexico, CAM, Cuba, Jamaica, Trinidad-Tobago, tropical SAM S to N Argentina (exc N Chile), now intro SE China; Mesechites 8 of 8 Neo endemic spp native CAM, Cuba, Hispaniola, Jamaica, Trinidad-Tobago, tropical SAM S to N Argentina (exc Uruguay and N Chile), inc 6 narrow endemics of Cuba (2), Hispaniola (1), Hispaniola + Jamaica (1), Colombia (1), Peru (1); Neobracea 8 of 8 narrow endemics of Cuba (7) and Cuba + Bahamas (1); Nerium monospecific Mediterranean sp intro CAM, S Brazil; Odontadenia 21 of 21 Neo endemic spp native CAM (exc El Salvador), Hispaniola, Colombia, N+E+C Brazil, Venezuela, Guyana, Suriname, French Guiana, Ecuador, Peru, Bolivia, Trinidad-Tobago, intro Windward Is, inc 4 narrow endemics of Brazil (2), COlombia (1), Hispaniola (1); Parahancornia 7 of 7 NW SAM endemic spp of Colombia, Venezuela, Guyana, Suriname, French Guiana, N Brazil, Peru, Bolivia; Pentalinon 2 of 2 Mexico, CAM & Caribbean endemic spp native Bahamas, Turks-Caicos, Greater Antilles, SW Caribbean, Leeward & Windward Is, Guatemala, Belize, El Salvador, Honduras, Nicaragua; Pinochia 4 of 4 Mexico & N Neo endemic spp native Guatemala, Belize, Nicaragua, Costa Rica, Panama, Greater Antilles (exc Cayman Is), inc 2 spp endemic to Greater Antilles; Prestonia 65 of 65 Mexico & Neo endemic spp native CAM, tropical SAM S to N Argentina (exc N Chile), Leeward & Windward Is, Trinidad-Tobago; Rhabdadenia 3 of 3 S NAM & Neo endemic spp native CAM, Bahamas, Greater Antilles, Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to N Argentina (exc N Chile); Secondatia 5 of 5 Neo endemic spp of Jamaica, Colombia, Venezuela, Guyana, Suriname, French Guiana, Brazil, Ecuador, Peru, Bolivia, Paraguay, inc 1 narrow endemic of Jamaica; Stipecoma monospecific SAM endemic of Bolivia, C+E Brazil; Strophanthus 1 of 39 Old World Tropics spp intro Trinidad-Tobago; Temnadenia 3 of 3 SAM endemic spp of Colombia, Brazil (exc N); Thenardia 1 of 3 S Mexico + Honduras endemic spp native  Honduras; Tintinnabularia 2 of 3 Mesoamérica endemic spp native Guatemala, Honduras, inc 1 narrow endemic of Honduras.

Asclepiadoideae: Ampelamus 1 of 3 Americas endemic spp endemic of Colombia; Anemotrochus 3 of 3 Caribbean endemic spp native Bahamas, Turks-Caicos, Cuba, Hispaniola, Jamaica; Araujia 13 of 13 former SAM endemic spp native Bolivia, C+SE+S Brazil, Paraguay, Uruguay, Argentina, intro C Chile, S USA and pantropical; Asclepias 12 of 206 Americas & Africa spp native CAM, Bahamas, Turks-Caicos, Antilles (exc Aruba), Trinidad-Tobago, Galapagos, most of SAM exc Chile, intro N Chile, genus is most diverse in NAM and Africa; Barjonia 7 of 7 Neo endemic spp of Brazil, Suriname, Bolivia; Blepharodon 26 of 26 spp Mexico & Neo endemic spp native CAM, SAM S to Peru, Bolivia, NE Argentina, S Brazil, inc 15 narrow endemics of Colombia (5), Brazil (5), Bolivia (2), Venezuela (2), Guyana (1); Calotropis 2 of 3 Old World Tropics spp intro Bahamas, Turks-Caicos, Antilles, Trinidad-Tobago, Colombia, Venezuela, N+C+E Brazil, Paraguay, Bolivia; Cristobalia 2 of 2 SAM spp of endemic Bolivia, N Argentina; Cynanchum 12 of 256 subcosmopolitan spp native in Mexico, CAM, Cuba, Jamaica, tropical SAM S to N Argentina (exc N Chile), most of genus is in Old World tropics; Diplolepis 9 of 14 spp S SAM endemic spp native N+C CHile, NW Argentina, inc 4 narrow endemics of N+C CHile (3), C Chile (1), rest of genus endemic to Patagonia Chile & Argentina; Ditassa 112 of 112 SAM endemic spp of Colombia S to N Argentina exc N Chile, Paraguay; Fischeria 8 of 8 Neo endemic spp native CAM (exc El Salvador), Cuba, Jamaica, Trinidad-Tobago, Colombia, Venezuela, Ecuador, Peru, Bolivia, Brazil, Paraguay, NE Argentina; Funastrum 12 of 21 former Americas endemic spp native Antilles ( exc Aruba, Leewards, Netherlands Antilles), Trinidad-Tobago, CAM, tropical SAM S to N Argentina (exc N Chile), inc 5 narrow endemics of Guatemala (1), Bolivia (1), Colombia (1), SE Brazil (1), Galapagos (1), 1 sp now intro India; Gomphocarpus 1 of 20 African & Arabian spp intro CAM (exc Belize), Cuba, Jamaica, Puerto Rico, Leeward Is, Colombia, Venezuela, Suriname, Brazil, Uruguay, NE Argentina, Ecuador, Peru, Bolivia; Gonolobus 119 of 119 former Americas endemic spp native from S USA, Mexico, Greater Antilles (exc Cayman Is), Leeward & Windward Is, CAM, tropical SAM S to N Argentina (exc N Chile, Suriname, French Guiana), now intro Africa; Gyrostelma monospecific endemic of C+SE Brazil; Hemipogon 8 of 8 SAM endemic spp of Peru, Brazil, Bolivia, Paraguay; Hoya 1 of 54 S Asia & Australasia spp intro Cuba, Trinidad-Tobago, Puerto Rico, Leeward Is; Hypolobus monospecific endemic NE Brazil; Ibatia 26 of 26 Neo endemic spp Panama, Cuba, Hispaniola, Puerto Rico, Lesser Antilles, Colombia, Venezuela, Guyana, Brazil, Paraguay, Ecuador, Bolivia, NE Argentina; Jobinia 25 of 25 Neo endemic spp native Guatemala, Honduras, Venezuela, Ecuador, Peru, Bolivia, C+S+E Brazil, N Argentina, Uruguay; Kerbera monospecific endemic SE Brazil; Lachnostoma 11 of 11 Neo endemic Colombia, Ecuador, Peru, Venezuela; Macroscepis 14 of 16 Mexico & Neo endemic spp native CAM (exc Belize), Colombia, Venezuela, Guyana, Ecuador, Peru, Bolivia, Paraguay, N Argentina, S+SE Brazil, inc 8 narrow endemics of S+SE Brazil (4), Colombia (1), Venezuela (1), Paraguay (1); Manothrix 2 of 2 spp endemic SE Brazil; Marsdenia ?? of 306 pantropical spp native CAM, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to N Argentina (exc N Chile); Matelea (inc Dictyanthus, Labidostelma) 271 of 271 Neo endemic spp native USA, Mexico, CAM, Bahamas, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to N Argentina (exc N Chile); Metastelma 100 spp of 100 Americas endemic spp native S USA, Mexico, Bahamas, Turks-Caicos, Antilles, CAM, Colombia, Venezuela, Guyana, N+E+S Brazil, Ecuador, Peru, Bolivia, Paraguay, N Argentina; Minaria 22 of 22 SAM endemic spp of Brazil, Bolivia, NE Argentina; Monsanima  2 of 2 narrow endemic spp of E Brazil; Morilloa  4 of 4 narrow endemic spp of E Brazil; Nautonia monospecific E SAM endemic of C+SE+S Brazil, Paraguay, NE Argentina; Nephradenia 5 of 5 N SAM endemic spp of Colombia, Venezuela, Guyana, N+E+C Brazil, Bolivia; Orthosia 38 of 38 Americas endemic spp native S USA, Mexico, CAM (exc Belize), Colombia, Venezuela, E+S Brazil, Uruguay, N Argentina, Ecuador, Peru, Bolivia, Paraguay, Bahamas, Greater Antilles (exc Cayman Is); Oxypetalum 135 of 135 Mexico & Neo endemic spp of Guatemala, Honduras, Costa Rica, Panama, Greater Antilles (exc Cayman Is), Leeward Is, Colombia, Venezuela, Guyana, Brazil, Ecuador, Peru, Bolivia, Paraguay, Uruguay, N Argentina; Pattalias 1 of 2 S NAM & Caribbean endemic spp native Belize, Bahamas, Turks-Caicos, Cayman Is, Cuba; Pentacyphus 3 of 3 N+W SAM endemic spp high Andean Venezuela, Colombia, Ecuador, Peru, inc 1 narrow endemic of Caldas Colombia; Peplonia 9 of 9 SAM endemic spp of Peru, Bolivia, E+C+S Brazil, Paraguay; Petalostelma 7 of 7 SAM endemic spp of Brazil, Bolivia, Paraguay, N Argentina; Phaeostemma 7 of 7 SAM endemic spp of Venezuela, Suriname, disnjunct S+SE Brazil, NE Argentina; Pherotrichis 1 of 4 Mexico & N CAM endemic spp native Guatemala; Philibertia 41 of 41 spp W+S SAM endemic spp of Ecuador, Peru, Bolivia, N+C Chile, Argentina; Polystemma 2 of 5 S NAM & CAM endemic spp native Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica; Pruskortizia 2 of 2 N SAM endemic spp of Colombia, Ecuador, Peru, Bolivia, N Brazil; Pseudolachnostoma 8 of 8 Neo endemic spp of Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, Venezuela, N Brazil, Trinidad-Tobago; Ptycanthera 2 of 2 spp endemic Cuba, Hispaniola; Rhytidostemma 8 of 8 Neo endemic spp of Panama, Colombia, Venezuela, Guyana, Suriname, French Guiana, C+N Brazil, Ecuador, Peru; Rojasia 2 of 2 SAM endemic spp of Bolivia, Paraguay, S Brazil, NE Argentina; Ruehssia 42 of 42 Mexico & Neo endemic spp native Costa Rica, Panama, Leeward & Windward Is, tropical SAM S to N Argentina (exc N Chile, Uruguay); Schistonema monospecific endemic Peru; Schubertia 6 of 6 SAM endemic spp of Colombia, Peru, Bolivia, Paraguay, Brazil, N Argentina; Scyphostelma 28 of 28 Neo endemic spp of Costa Rica, Panama, Colombia, Venezuela, Ecuador, Peru, Bolivia; Stephanotis 1 of 4 Madagascar spp intro Cuba, Hispaniola, Puerto Rico, Leeward Is, Trinidad-Tobago; Tassadia 31 of 31 Neo endemic spp native S Mexico, Cuba, Trinidad-Tobago, Belize, Nicaragua, Costa Rica, Panama, tropical SAM S to Peru, Bolivia, Paraguay, S Brazil; Topea 2 of 2 narrow endemic spp of NE Argentina; Tressensia monospecific endemic NE Argentina; Tweedia 6 of 6 SAM endemic spp Bolivia, N+C Chile, Argentina, Paraguay, inc 4 narrow endemics of C Chile (2), N+C Chile (1), NW Argentina (1); Tylodontia 4 of 4 narrow endemic spp of Cuba; Vailia monospecific W SAM endemic of Ecuador, Bolivia, Peru.  

Periplocoideae: Cryptostegia 2 of 2 Madagascar spp intro CAM (exc Guatemala, Belize), Bahamas, Antilles, Trinidad-Tobago, Colombia, Venezuela, N+NE+C Brazil.

Rauvolfioideae: Allamanda 15 of 15 former Neo endemic spp native Honduras, Nicaragua, Costa Rica, Panama, Colombia, Venezuela, French Guiana, Guyana, Suriname, Brazil, Bolivia, Peru, NE Argentina, intro in Guatemala, Belize, El Salvador, Trinidad-Tobago, Galapagos and pantropical; Alstonia ?? of 44 pantropical spp native CAM (exc Belize), intro Trinidad-Tobago, absent SAM; Ambelania 3 of 3 SAM endemic spp Colombia, Venezuela, Peru, N+NE Brazil, French Guiana, Guyana, Suriname; Anechites monospecific Neo endemic Honduras S to Colombia, Venezuela, Ecuador, Peru, Greater Antilles (exc Cayman Is); Aspidosperma 77 of 77 Neo endemic spp native from S Mexico S through CAM and tropical SAM S to N Argentina (exc N Chile), Hispaniola, Trinidad-Tobago, Venezuelan Antilles; Cameraria 7 of 7 spp former Mexico & N Neo endemic spp native Belize, Guatemala, Cuba, Hispaniola, Jamaica, Greater Antilles, inc 6 single island endemics of Cuba (4), Hispaniola (1), Dominican Republic (1), 7th sp is wider ranging and now intro SE China; Carissa 1 of 9 Old World Tropics spp Honduras, Nicaragua, Bahamas, Jamaica, Puerto Rico, Leeward & Windward Is, Trinidad-Tobago; Catharanthus 1 of 9 Indian & Madagascar spp intro CAM, Bahamas, Turks-Caicos, Antilles (exc Cayman Is, Venezuelan Antilles), SW Caribbean, Galapagos, French Guiana; Cerbera 1 of 6 Old World Tropics spp intro Trinidad-Tobago; Chamaeclitandra monospecific African sp intro Trinidad-Tobago; Condylocarpon 7 of 7 Neo endemic spp of Nicaragua, Colombia, Venezuela, Brazil, French Guiana, Guyana, Suriname, Paraguay, Peru, Uruguay, NE Argentina, Trinidad-Tobago; Couma 5 of 5 Neo endemic spp Guatemala, Belize, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Venezuela, Suriname, Guyana, French Guiana, N+NE Brazil, Ecuador, Peru, Bolivia; Geissospermum 5 of 5 SAM endemic spp of Venezuela, Guyana, Suriname, French Guiana, N+E Brazil, Peru, Bolivia; Hancornia monospecific SAM endemic of Bolivia, Brazil, Paraguay, Peru; Haplophyton 2 of 2 S NAM & N CAM endemic spp native Cuba, Guatemala; Himatanthus 9 of 9 Neo endemic spp Panama, Colombia, Ecuador, Peru, Bolivia, Brazil, Venezuela, French Guiana, Guyana, Suriname; Kopsia 1 of 24 mostly Australasian spp intro Trinidad-Tobago; Lacmellea 24 of 24 Neo endemic spp native Guatemala, Belize, Honduras, Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, Bolivia, N+C+E Brazil, Venezuela, Guyana, Suriname, French Guiana; Landolphia 1 of 63 African spp intro Trinidad-Tobago; Laxoplumeria 5 of 5 Neo endemic spp of Panama, Colombia, Ecuador, Peru, Bolivia, N+C+SE Brazil, French Guiana; Macoubea 3 of 3 Neo endemic spp Costa Rica, Panama, Colombia, Peru, Bolivia, Venezuela, Guyana, Suriname, French Guiana, N+NE Brazil; Microplumeria monospecific N SAM endemic of Colombia, Venezuela, N Brazil; Molongum 3 of 3 N SAM endemic spp of Colombia, Venezuela, N Brazil; Mortoniella monospecific CAM endemic of Belize, Nicaragua, Costa Rica; Mucoa 2 of 2 N SAM endemic spp of Colombia, Venezuela, N Brazil, Peru; Neocouma  2 of 2 N SAM endemic spp of Colombia, Venezuela, Peru, N Brazil; Pacouria 3 of 3 N SAM endemic spp of Colombia, Venezuela, Guyana, Suriname, French Guiana, N+SE Brazil, Bolivia, Peru; Plumeria 19 of 19 former Americas endemic spp native CAM, Colombia, Venezuela, Guyana, Bahamas, Turks-Caicos, Antilles (exc Aruba, Netherlands Antilles), SW Caribbean, intro Ecuador, Peru, Bolivia, Paraguay, Netherlands Antilles, Trinidad-Tobago, and 2 spp now intro tropical Asia, Africa; Rauvolfia ?? of 74 spp pantropical spp native CAM, Antilles (exc Netherlands Antilles), tropical SAM S to N Argentina (exc Uruguay, N Chile); Rhigospira monospecific N SAM endemic spp of Colombia, Venezuela, N Brazil, Peru; Skytanthus 3 of 3 narrow SAM endemic spp of E Brazil (2), N+C Chile (1); Spongiosperma 6 of 6 N SAM endemic spp of Colombia, Venezuela, N+NE Brazil; Strempeliopsis 2 of 2 narrow single island endemic spp of Cuba (1), W Jamaica (1); Tabernaemontana ?? of 123 pantropical spp native Antilles (exc Aruba, Netherlands Antilles), SW Caribbean, tropical SAM S to Peru, Bolivia, NE Argentina; Thevetia 3 of 3 Mexico & Neo endemic spp native CAM, Cuba, Colombia, Venezuela, N+C Brazil, Bolivia, Paraguay, NE Argentina; Vallesia 6 of 11 Americas endemic spp native Cuba, Hispaniola, Jamaica, Belize, Guatemala, El Salvador, Honduras, Costa Rica, Colombia, Venezuela, N Brazil, Peru, Bolivia, Paraguay, N Argentina, inc 2 narrow endemics of Galapagos (1), Venezuela (1); Vinca 2 of 7 Mediterranean spp intro Guatemala, Costa Rica, Colombia, Venezuela, Bolivia, C Chile, Uruguay.    

Patagonia Genera Include:

Apocynoideae: Elytropus monospecific endemic C+S Chile, S Argentina. 

Asclepiadoideae:  Asclepias 1 of 206 Americas & Africa spp native S Argentina; Diplolepis 10 of 14 spp S SAM endemic spp native SC+S Chile, S Argentina, inc 5 narrow endemics of S Argentina (3), SC+S Chile (1), Patagonia (1); Philibertia ?? of 41 spp W+S SAM endemic spp native C Chile, S Argentina; Tweedia 2 of 6 spp SAM endemic native C Chile, 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 (2023).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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/
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

9 Oct, 2022

28 Sep, 2022

How to Identify the Aristolochiaceae or Birthwort Family

Aristolochia taliscana flower of the Aristolochiaceae family. Photo by Lyrae Willis taken at Paco's Nature Reserve in Mazatlan, Sinaloa, Mexico, 2021. Notice all of the elaborate hairs that help to guide and trap the insects inside the mouth of the tube.
Aristolochia taliscana flower of the Aristolochiaceae family. Photo by Lyrae Willis taken at Paco’s Nature Reserve in Mazatlan, Sinaloa, Mexico, 2021. Notice all of the elaborate hairs that help to guide and trap the insects inside the mouth of the tube.

Table of contents

Introduction to the Aristolochiaceae Family

The Aristolochiaceae are a family with bizarre-looking flowers, and each genus has its own unique morphology. Since I always love the bizarre, the first time I saw an Asarum and an Aristolochia, I was instantly in love with their unique beauty. APG IV recently combined two very small families into it otherwise, it would 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, which will be described in detail as one (differences between these two subfamilies can still be found in the Taxonomy section below.

Flowers of Aristolochiaceae

Flowers of Traditional Aristolochiaceae

Plants are hermaphrodite. Pollination is entomophilous by Diptera, and the mechanism is conspicuously specialized via an elaborate system for trapping flies within the perianth tube using articulated hairs that end up withering to release the flies so they can visit another flower. Flowers can be solitary or aggregated in cymes, racemes, or spikes, and they are often axillary but sometimes terminal. Flowers are very unusual in shape and can be small, medium, or large. They are often malodorous and smelling of carrion or may be odorless. They are actinomorphic to zygomorphic and tricyclic to pentacyclic. The perianth has 3 or 6 parts that are joined in one whorl or two (then isomerous), and they either have a distinct calyx and corolla or are petaline. Only in Saruma is the corolla whorl conspicuous and well developed. The calyx has three parts in one whorl: connate, entire or blunt-lobed, and campanulate or tubular, with the tube often S-shaped. The calyx is unequal but not bilabiate, bilabiate, or regular, persistent or not, and valvate or valvate–induplicate. Corolla, when present, has three parts in one whorl but otherwise is usually reduced or absent.

Flowers of Hydnoroideae

Plants 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, often with the lower parts remaining beneath the soil. They are medium to large in size, malodorous, regular, and either tricyclic or tetracyclic. A short free hypanthium is present. The perianth is sepaline, petaline, or of tepals. It has 3–4(5) parts joined in one whorl. The lobes are valvate, fleshy, often bare retrorse bristles, and are white, red, pink, or brown in color. 

Flowers of Lactoridoideae

Plants are polygamodioecious with axillary flowers that are solitary or aggregated in cymes. Flowers are small, 3 merous, and tetracyclic. There is no free hypanthium or hypogynous disk. The perianth has three parts in one whorl and is sepaline.

Androecium of Aristolochiaceae

Androecium of Traditional Aristolochiaceae

The androecium has 6–36 members in one or two whorls that are free of the perianth but may be free of or united with the gynoecium or coherent via the gynostemium and one adelphous. Often, there are six stamens but may also be 4 or 12(13–36), and they are all exclusively fertile. Stamens are isomerous with the perianth to polystemonous and are either filantherous or have sessile anthers. Anthers are cohering or separate from one another, basifixed or adnate, non-versatile, and dehiscing via longitudinal slits. They are extrorse or both extrorse and introrse only in Heterotropa. Anthers are tetrasporangiate and appendaged apically with the expanded connective that assumes stigmatic functions associated with the gynostemium, or they are unappendaged.

Androecium of Hydnoroideae

The androecium has 3–4(5) or 6–8(9–10) members that are free of the perianth but inserted on the hypanthium. They are one whorled, coherent, and united into a thick sinuose annular in Hydnora or an ovoid synandrium. The androecium is either made exclusively of fertile stamens or, in Prosopanche, includes staminodes. In Prosopanche 3–4(5), small fleshy staminodes alternate with the stamens. There are 3–4(5) stamens that are oppositisepalous and isomerous with the perianth. They either have sessile anthers in Hydnora or are filantherous in Prosopanche, where the very short filaments arise from the hypanthium, and the anthers are connate to form a dome or cap with a small central opening. Anthers may be separate from one another or coherent in Prosopanche. They are dehiscing via longitudinal slits or transversely, are extrorse, and many locular where each one has numerous pollen sacs.

Androecium of Lactoridoideae

There are six androecial members that are free of the perianth and one another and are two whorled. The androecium is either exclusively all fertile stamens or sometimes includes staminodes. When present, three non-petaloid staminodes are internal to the fertile stamens. There are 6(3) stamens that are diplostemonous, narrowly laminar, and short. Anthers are adnate, non-versatile, and dehiscing via longitudinal slits. They are extrorse, bilocular, and almost as long as the blade. Anthers are tetrasporangiate and shortly appendaged apically. 

Gynoecium of Aristolochiaceae

Gynoecium of Traditional Aristolochiaceae

The gynoecium has 4–6 carpels, and the pistil has 1 or 4–6 cells. It is synstylovarious, syncarpous, or in Hexastylis, it is synovarious. The gynoecium is usually inferior but sometimes may be partly inferior. The ovary is either 4–6 or 1 locular (where the septa are sometimes incompletely intruded). An epigynous disk is either present or absent. There are 1 or 4–6 free or partially joined styles that are apical. Placentation when unilocular is parietal and when plurilocular it is axile. There are 50-100 ovules in a single cavity if unilocular and 20-50 when plurilocular. Ovules possess a funicle, are pendulous or horizontal, and are anatropous.

Gynoecium of Hydnoroideae

The gynoecium is 3(4) carpelled and is either partly or completely buried in the soil. The pistil is one-celled. The gynoecium is synstylovarious to syncarpous and inferior. The ovary is one locular but becomes occluded by ingrowth of the accrescent placentas. There are 1 or 3 sessile and commissural (Prosopanche) stigmas that are mostly 3-lobed in Hydnora. Placentation is parietal (Prosopanche) or apical (Hydnora). There are 50-200 undifferentiated ovules in the single cavity that are orthotropous and tenuinucellate.

Gynoecium of Lactoridoideae

The gynoecium is three-carpelled and isomerous with the perianth. The pistil is basally three-celled. It is superior and semicarpous with the carpels in a single whorl and more or less basally connate. The carpel is shortly stylate with a decurrent stigma and 6(4–8) ovuled. Placentation is marginal, and the placenta is intruded. The ovary is three locular basally. Ovules have long funicles, are biseriate, anatropous, bitegmic, and weakly crassinucellate.

Fruit of Aristolochiaceae

Fruit of Traditional Aristolochiaceae

The fruit is usually non-fleshy, but sometimes it has a fleshy endocarp. Usually, they are dehiscent septicidal, valvular (usually basally but only rarely at the top), or an irregularly splitting capsule. Rarely are they an indehiscent berry or a nut, or in Saruma, they area schizocarp with 4-6 mericarps of follicles. Seeds are endospermic, ruminate or not, and are oily. The Embryo is rudimentary to weakly differentiated at the time of seed release.

Fruit of Hydnoroideae

The fruit is fleshy inside but with a more or less woody pericarp. It is a dehiscent circumscissile capsule (Prosopanche) or an indehiscent capsule or berry. Fruits contain 500–2000 tiny seeds that are endospermic.

Fruit of Lactoridoideae

The fruit is a non-fleshy aggregate with the fruiting carpels coalescing into a secondary syncarp, a dehiscent follicle. Seeds are endospermic and oily.

Habit & Leaf Form of Aristolochiaceae

Habit & Leaf Form of Traditional Aristolochiaceae

Shrubs, lianas, or herbs, but mostly woody vines bearing essential oils. Plants are green and photosynthesize. They are always perennial and do not have a conspicuous aggregation of leaves. They are usually climbing stem twiners, but sometimes they are self-supporting. Plants are mesophytic. Leaves are alternate, spiral, flat, and either herbaceous or herbaceous and membranous. They are petiolate, sheathing to non-sheathing, simple, aromatic, and may be gland-dotted pellucid punctate. Lamina is usually entire or sometimes dissected palmatifid or trilobed and is often cordate. They are either palmately or pinnately veined and are cross-venulate. Leaves are exstipulate, but sometimes the first 1–2 leaves of suppressed axillary branches simulate stipules.  

Habit & Leaf Form of Hydnoroideae

Ectoparasitic herbs with a very peculiar vegetative form that lacks leaves and is more or less fungoid in habit. The vegetative component consists of a coarse, rhizome-like pilot root with many slender, unbranched haustorial roots that parasitize the roots of host plants). Plants are succulent and not green. 

Habit & Leaf Form of Lactoridoideae

Shrubs bearing essential oils with small, simple, alternate, distichous, petiolate, and gland-dotted leaves. The lamina is entire, obovate, emarginate, and pinnately veined. 

Uses of the Aristolochiaceae Family 

A few Aristolochia and Asarum spp are routinely cultivated as ornamentals. Aristolochia and some Asarum contain a toxin known to be carcinogenic to humans and rates, so they are never ingested in any way. However, Pipevine Swallowtail butterflies are immune to the toxin and lay their eggs on Aristolochia spp, and their caterpillars eat the leaves when they hatch. The fruits of Hydnora, on the other hand, have edible, fragrant pulp, which attracts animals, including porcupines, monkeys, jackals, rhinoceros, and armadillos, and are sometimes eaten by humans.

Morphology of Aristolochiaceae in North America

Side view of Aristolochia taliscana, notice the lack of a true corolla, it is a petaline calyx fused into the S-shaped tube often seen in the Aristolochiaceae. Also, notice the hairs that help trap the insects (see also the photo at the top of the page for great hairs!).
Side view of Aristolochia taliscana, notice the lack of a true corolla, it is a petaline calyx fused into the S-shaped tube often seen in the Aristolochiaceae. Also, notice the hairs that help trap the insects (see also the photo at the top of the page for great hairs!).
Front view of an Asaraum caudatum flower showing the three-part petaline calyx and the androecium in the center made of 12 stamens coherent in a tube. These features are very typical features of the Aristolochiaceae family (except for 12 stamens).
Front view of an Asaraum caudatum flower showing the three-part petaline calyx and the androecium in the center made of 12 stamens coherent in a tube. These features are very typical features of the Aristolochiaceae family (except for 12 stamens).
Hexastylis arifolia flowers are typically urceolate (urn-shaped), giving it the common name of Little Brown Jugs (flowers are usually browner than these)
Hexastylis arifolia flowers are typically urceolate (urn-shaped), giving it the common name of Little Brown Jugs (flowers are usually browner than these)
Fruit of Aristolochia watsonii is a septicidal capsule with 5 valves and it dehisces basally (at the stem), these are common features of the Aristolochiaceae.
Fruit of Aristolochia watsonii is a septicidal capsule with 5 valves and it dehisces basally (at the stem), these are common features of the Aristolochiaceae.
Dehisced fruit of Aristolochia taliscana. Basally dehiscing septicidal capsules are common in the Aristolochiaceae.
Dehisced fruit of Aristolochia taliscana. Basally dehiscing septicidal capsules are very common in the Aristolochiaceae.
The leaf of Asaraum caudatum is simple, entire, cordate, and with palmate venation and cross venules. All these features are common in Aristolochiaceae.
The leaf of Asaraum caudatum is simple, entire, cordate, and with palmate venation and cross venules. All these features are standard in Aristolochiaceae.
Aristolochia watsonii has a sagittate leaf which is less common in Aristolochiaceae, but it shows the petiole and the palmate venation common in the family.
Aristolochia watsonii has a sagittate leaf which is less common in Aristolochiaceae, but it shows the petiole and the palmate venation common in the family.
This Aristolochia taliscana plant shows the cordate leaves and vine habit so common in the Aristolochiaceae family.
This Aristolochia taliscana plant shows the cordate leaves and vine habit so common in the Aristolochiaceae family.

Species of Aristolochiaceae I have Covered So Far

Aristolochioideae Subfamily

Aristolochia taliscana is a vine w cordate leaves & axillary flowers w S-shaped petaline calyx in burgundy, purple, or brown usu w yellow, calyx covered with hairs. Limited to W Mexico. Of the Aristolochiaceae family.

Aristolochia taliscana – Mexican Birthwort

This is a lush medium green vine with cordate leaves with a deep cleft and a rounded to emarginate tip. Flowers are solitary and axillary with an S-shaped petaline calyx in burgundy, purple, or brown, usually with yellow markings. The calyx limb is covered with conspicuous purple hairs that trap pollinating insects. Native to western Mexico.

Aristolochia watsonii deeply sagittate leaves w various purple shades. Calyx straight or S-shaped , limb w maroon spots & no elaborate hairs. Native range is SW USA, NW Mexico. Of the Aristolochiaceae family.

Aristolochia watsonii – Watson’s Dutchman’s Pipe

This one has very deeply sagittate green leaves with various purple markings. Calyx tube is straight or S-shaped and the limb has maroon spots and no elaborate hairs. Native to southwestern USA, northwestern Mexico.

Asaroideae Subfamily

Note that the genus Hexastylis was recently combined in with the Asarum based on phylogenetic research, though not all sources have accepted this. Since it is still not widely accepted, and their floral morphology is different, I have kept it separate for now.

Asarum caudatum has cordate leaves w long petioles, single burgundy or greenish-yellow flowers w 3 part calyx w very long acute lobes tapering to a fine point. Native to PNW. Of the Aristolochiaceae family.

Asarum caudatum – Western WIld Ginger

This has classic cordate leaves with very long petioles from the ground up. Flowers are solitary and burgundy or greenish-yellow, with a 3 part calyx with very long acute lobes tapering to a fine point. Native to the Pacific Northwest from BC, Canada south to California, east to Idaho, Montana, USA.

Hexastylis arifolia w triangular-sagittate or ovate-sagittate to deltate leaves that are often variegated. Flowers urceolate in brown, purple or reddish w 3 lobes flared/not. Native SE USA. Of the Aristolochiaceae family.

Hexastylis arifolia Little Brown Jug

This low herbaceous perennial has triangular-sagittate, ovate–sagittate, somewhat cordate, to deltoid leaves that are often variegated. Flowers are urceolate (jug-shaped) in brown, purple, or reddish with 3 lobes that may or may not be flared. Native to the southeastern USA.

Hexastylis shuttleworthii has orbicular to cordate & usu variegated leaves, its flowers similar to H. arifolia but much large flowers. Range limited to the S Appalachians & srnd area. Of the Aristolochiaceae family.

Hexastylis shuttleworthii – Shuttleworth Ginger

This one has orbicular to cordate & usually variegated leaves. Its flowers are similar to H. arifolia but much larger. Its a narrow endemic of the southern Appalachians & the surrounding area, eastern USA.

Taxonomy of Aristolochiaceae

The Aristolochiaceae family has 500-700 spp in 8 genera of the Piperales Order in the Magnoliids Clade of Basal Angiosperms. This clade is not part of either the monocots or the dicots. APG IV has combined the former Hydnoraceae and Lactoridaceae because their exclusion would make the Aristolochiaceae paraphyletic.

  1. Aristolochioideae – Plants are mostly lianas or occasionally shrubs or herbs. Inflorescences are usually axillary, and the flowers or at least the floral buds, are zygomorphic. The gynoecium has 4-6(2-3) carpels that are constricted apically. Stigmas are wet or dry and are commissural in Aristolochia. Fruits are dehiscent and open laterally, acropetally or basipetally septicidal, or rarely adaxially if a schizocarp or berry. Seeds are winged.
  2. Asaroideae – Plants are rhizomatous perennial herbs. Flowers are solitary and terminal, the gynoecium is inferior to half inferior, and the stigma has multicellular papillae. The fruit of the Asarum is an irregularly dehiscent capsule and a follicular schizocarp in Saruma. 
  3. Hydnoroideae – see descriptions above for a complete description.
  4. Lactoris or Lactoridoideae – see descriptions above for a complete description.

Genera:

Aristolochioideae: Aristolochia (~400 – 565 inc Isotrema, Euglypha, Pararistolochia), Thottea (43 inc Apama).

Asaroideae: Asarum (126 inc Heterotropa, Hexastylis), Saruma (1).

Hydnoroideae: Hydnora (6), Prosopanche (4).

Lactoridoideae: Lactoris monospecific Lactoris fernandeziana.

Key Differences From Similar Families

The unique flowers of most members of the Aristolochiaceae make them hard to confuse with other families. The subfamilies Aristolochioideae and Asaroideae are so unique they are rarely confused, and the Lactoroideae is a rare microendemic from Juan Fernandez Island. The Hydnoroideae, on the other hand, despite its uniqueness, do have some superficially similar-looking families. However, the other families all contain features lacking in Hydnoraceae. They include the Apodanthaceae with its very small unisexual flowers, the Balanophoraceae with its fungus-like inflorescence with numerous small flowers, the Cytinaceae with its spicate inflorescence, the Mitrastemonaceae with its whorl of opposite decussate leaves and a superior ovary, and the Orobanchaceae with its zygomorphic flowers on racemes or spikes.   

Distribution of Aristolochiaceae

The Aristolochiaceae family is widespread in warm temperate to tropical areas around the world except in Australasia, and they are not present in arctic areas. The Lactoridoideae is a rare microendemic genus confined to Juan Fernandez Island off the coast of Chile.

Distribution of Aristolochiaceae in the Americas

Canadian Genera Include:

Aristolochioideae: Aristolochia 1 of 525 cosmopolitan spp native ON, intro QC; Isotrema 1 sp intro ON. Asaroideae: Asarum 2 of 126 N temperate spp native BC, MB, ON, QB, NB.

USA Genera Include:

Aristolochioideae: Aristolochia 16 of 525 cosmopolitan spp intro and native to most of the USA exc WA, OR, NV, UT, ID, MT, WY, CO, ND, SD, NE, MN, VT. Asaroideae: Asarum (inc Hexastylis) 17 of 126 N temperate spp native in most of the USA exc NV, AZ, UT, WY, CO, NM, NE, TX.

Mexico Genera Include:

Aristolochioideae:Aristolochia 47 of 525 cosmopolitan spp native throughout all of Mexico inc Mexican Pacific Is. Asaroideae:Asarum (inc Hexastylis) 1 of 126 N temperate spp native Yuc.

Neotropical Genera Include:

Aristolochioideae: Aristolochia ~200 of 525 cosmopolitan spp native throughout Mexico, CAM, Bermuda, Bahamas, Cuba, Hispaniola, Jamaica, Puerto Rico, Leeward & Windward Is, tropical SAM S to Santiago C Chile, N Argentina, intro Venezuelan Antilles, Galapagos, inc 15 spp formerly known as Isotrema native in CAM and Euglypha a former monospecific genus endemic to Bolivia, C+SE Brazil, Paraguay, NE Argentina. Hydnoroideae: Prosopanche 4 of 4 CAM + SAM endemic spp native Costa Rica, Peru, Bolivia, Argentina, Paraguay, NE+S Brazil inc 2 narrow endemics of Costa Rica (1), Bahia Brazil (1). Lactoridoideae: Lactoris 1 sp endemic of Juan Fernandez Island off the coast of Chile. 

Patagonia Genera Include:

Hydnoroideae: Prosopanche 1 of 4 CAM + SAM endemic spp native 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 (2022).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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/
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

28 Sep, 2022

25 Sep, 2022

How to Identify the Amaranthaceae Family

Achyranthes aspera has a spike inflorescence & tiny flowers hidden by bracts.
Achyranthes aspera has a spike inflorescence & tiny flowers hidden by bracts.

Table of contents

Introduction to the Amaranthaceae Family

 The Amaranthaceae family is part of the Caryophyllales Order of core Eudicots. It is made of mostly herbs or shrubs, or sometimes lianas. Inflorescences are typically elongated spikes, heads, compact cymes, or panicles and their flowers are mostly very small and inconspicuous with a sepaloid or non-existent perianth. Flowers are frequently surrounded by bracts that may or may not be persistent, and fruits are usually small and non-fleshy. The Amaranthaceae are often found growing in disturbed habitats, and many of them are introduced weeds, sometimes considered noxious. Many edible plants come from Amaranthaceae, including beets, quinoa, amaranth, spinach, and swiss chard.

Flowers of Amaranthaceae

Plants are usually hermaphrodite but otherwise monoecious, andromonoecious, gynomonoecious, dioecious, androdioecious, or polygamomonoecious (rarely).  Flowers are solitary, paired (axillary), or aggregated in terminal or axillary cymes, spikes, heads (often with conspicuous persistent bracts and bracteoles), panicles, or thyrses, and they may or may not be pseudanthial. Flowers are small to minute in size, they are bracteate and bracteolate, regular, and tricyclic when hermaphrodite, otherwise sometimes, they are cyclic or two-cyclic. Free hypanthium is usually absent except sometimes in the Chenopodioideae. The hypogynous disk is absent except in Chenopodioideae, where it is usually present. The perianth is dry and scarious, sepaloid or petaloid, or may be vestigial or absent (sometimes in Chenopodioideae). When present, there are 3–5(1-6) parts to the perianth. The perianth is typically interpreted as a calyx with 3–5 (1-6) parts that may be free, partially connate, or connate (almost always in Chenopodioideae). The calyx is regular, imbricate, usually non-fleshy except in Chenopodioideae, persistent in fruit, and may or may not be accrescent, enclosing the fruit with wings, tubercles, or spines. 

Androecium of Amaranthaceae

The androecium has 2-5 (1–10) members that are either free of the perianth or adnate to the perianth or disk. All members are usually unequal except in the Chenopodioideae and some Ptilotus, where they are all equal.  They are always in one whorl and are usually basally coherent 1 adelphous with filaments usually connate all or part of their length into a membranous tube, or in Chenopodioideae, they are often free of one another. The androecium can be made of exclusively fertile stamens (sometimes, or usually in Chenopodioideae) or may often include staminodes with some members lacking anthers or with petaloid or with pseudostaminodial scales alternating with the true androecial members.  When present, there are 1–3 or 5 staminodes in the same series as fertile stamens, and they may or may not be petaloid. There are 3-5(1) stamens that are oppositisepalous and usually isomerous with the perianth. Anthers dehiscing via longitudinal slits, and they are  introrse, unilocular to bilocular, and either bisporangiate or tetrasporangiate.  

Gynoecium of Amaranthaceae

The gynoecium is 2–3(4-5) carpelled, often 5 carpelled in Chenopodioideae, and the pistil 1 celled. The gynoecium is synovarious, synstylovarious, or syncarpous, and it is usually superior but can sometimes be partly inferior. Ovary is 1 locular and sessile to stipitate. The gynoecium may be non-stylate or stylate, when present, there are 1–3(2-4) styles that may be partially joined.  There are 1-3 stigmas 1–3 that are dry type, papillate, and Group II type. Placentation is always basal. There are 1 or 2-5 ovules in the single cavity, and they are ascending or pendulous, non-arillate, campylotropous, bitegmic, and crassinucellate.

Fruit of Amaranthaceae

The fruit may be fleshy or non-fleshy. It may be a dehiscent irregular or often circumscissile capsule, or it may be an indehiscent berry, drupe, nut, capsule, or often a utricle. Sometimes in the Chenopodioideae, the fruit may be enclosed in the fleshy hypanthium or perianth, and sometimes, the gynoecia also combine to form a multiple fruit. Seeds are non-endospermic and contain starch. Perisperm is present (abundant, mealy) or sometimes absent in Chenopodioideae. Seeds have starch.

Habit & Leaf Form of Amaranthaceae

Most are annual or perennial (sometimes biennial) herbs or subshrubs, some shrubs, and a few vines and small trees. Sometimes they are succulent and nearly always halophytic in the Chenopodioideae, where they can even be more or less cactoid with succulent photosynthetic stems (Salicornia). Many species have thickened nodes on their stems. The wood of the perennial stem has a typical anomalous secondary growth, and only the subfamily Polycnemoideae has normal secondary growth. Plants are green and photosynthesizing. Leaves may be well-developed, much-reduced, or absent, and they may be minute to large in size. Usually without a basal aggregation of leaves except sometimes in Ptilotus and the Chenopodioideae. The leaves are arranged alternate or opposite, and they are usually herbaceous but can also be fleshy or membranous. They are simple and may be petiolate or sessile, exstipulate, epulvinate, connate or not, sheathing or not, and flat or terete. Leaves can be extremely variable in shape, with mostly entire or occasionally toothed margins. The lamina is entire and is either one-veined or pinnately veined. A variety of hairs are often present.  Domatia are common. 

Uses of Amaranthaceae 

A few cultivated ornamentals from Amaranthus, Gomphrena, Iresine, and some noxious weeds, notably from Amaranthus, Iresine, Acnida. Amaranthus is also used as food in many parts of the world. In North America, natives used to cultivate it for both the greens which are eaten as a vegetable and the seeds which were often ground into flour.  Amaranth seeds and flour are a suitable replacement for wheat for those with grain allergies and gluten intolerance. Other commercially grown species include the sugar beet and Swiss chard from Beta vulgaris and spinach (Spinacia oleracea).

Morphology of Amaranthaceae in North America

Drooping panicles made of spike of small flowers, common in Amaranthaceae. From Amaranthus palmeri
Drooping panicles made of spike of small flowers, common in Amaranthaceae. From Amaranthus palmeri
Spike inflorescence of Achyranthes aspera also shows bracts & bracteoles common in Amaranthaceae.
Spike inflorescence of Achyranthes aspera also shows bracts & bracteoles common in Amaranthaceae.
Head of Gomphrena serrata w conspicuous bracts, Amaranthaceae often w bracts longer than flowers
Head of Gomphrena serrata w conspicuous bracts, Amaranthaceae often w bracts longer than flowers
Small flowers in leafy bracts of Bassia scoparia, almost all Amaranthaceae have small or tiny flowers w bracts
Winged Sepals of Salsola kali ssp tragus, as w many Amaranthaceae it’s perianth is sepaloid, these are larger than most, however
Persistent winged bracts of Atriplex canescens, persistent bracts are seen in many Amaranthaceae
Persistent winged bracts of Atriplex canescens, persistent bracts are seen in many Amaranthaceae
Rhombic leaves of Chenopodium album, common in many Amaranthaceae members
Rhombic leaves of Chenopodium album, common in many Amaranthaceae members
Terete leaves of Halogeton glomeratus are another common leaf form among Amaranthaceae
Terete leaves of Halogeton glomeratus are another common leaf form among Amaranthaceae
Reduced and spine-tipped leaves of Salsola kali ssp tragus, reduced leaves common in Amaranthaceae & spine-tipped leaves common in Salsoideae subfamily.
Reduced and spine-tipped leaves of Salsola kali ssp tragus, reduced leaves common in Amaranthaceae & spine-tipped leaves common in Salsoideae subfamily.
Tumbleweed of Salsola kali ssp tragus, many Amaranthaceae form tumbleweeds, this species is the most common large one in W North America.
Tumbleweed of Salsola kali ssp tragus, many Amaranthaceae form tumbleweeds, this species is the most common large one in W North America.

Amaranthaceae Species I have Covered So Far in North America

Amaranthoideae Subfamily

Achyranthes aspera – Chaff Flower

This is a tall herb, up to 2 m tall, with pilose to puberulent stems and variable leaves that are often roughly obovate, suborbicular, etc. Sessile flowers are in a long spike surrounded by persistent awned bracts and bracteoles. Pantropical herbs were introduced to the southern USA and Mexico.

Amaranthus hybridus – Smooth Pigweed

This is a hybrid species that readily hybridizes with numerous other species. It has highly variable morphology. Similar to Amaranthus palmeri, it grows to 2.5 m tall, and the stems are usually glabrous (hairless). Native to eastern North America but now widely introduced elsewhere.

Amaranthus palmeri – Palmer’s Amaranth

Is an herb that grows to 1.5 m (rarely to 3 m) tall. Stem and leaves are nearly glabrous, and the rhombic leaves have long petioles. Flowers are in terminal (only) spikes or drooping panicles. Native to southern North America but now widely introduced.

Amaranthus retroflexus – Red Root Amaranth

It is a tall herb, growing to 3 m tall, is pubescent 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 is an annual herb up to 1.5 m tall, with linear-lanceolate leaves that often curl, and a stem that is often red. Inconspicuous flowers in leaf axils with 0.5 -1 cm long bracts. Highly invasive Eurasian introduced species.

Bassia scoparia – Summer Cypress

It is an annual herb up to 1.5 m tall, with linear–lanceolate leaves that often curl, and a stem that is often red. Inconspicuous flowers in leaf axils with 0.5 -1 cm long bracts.
Highly invasive Eurasian introduced species.

Chenopodioideae Subfamily

Atriplex canescens ~ sessile ~ oblong leaves, conspicuous winged greenish bracteoles in fruit that turn papery & beige when mature, few spines on branches. Native W + mid-W USA; of the Amaranthaceae Family

Atriplex canescens – Four Wing Saltbush

Has more or less sessile, somewhat oblong leaves, and conspicuous winged greenish bracteoles in fruit that turn papery & beige when mature (see photo). There are few spines on their branches. Native to western & midwestern USA

Atriplex confertifolia – Spiny Saltbrush

It is similar to A. canescens but with shorter, wider leaves, unwinged fruits, and many more spines on its branches. 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 that are 3 – 10 cm long and more than half as wide, with irregular large pointy teeth, lobes, or lobules (of varying depths), with mostly hairless stems & leaves and small apetalous flowers. Native to much of North America.

Chenopodium album – White Goosefoot

This is a very common erect annual with striations on its stems in green or reddish-purple; leaves are rhombic–ovate to broadly lanceolate. Flowers are in compact cymes in terminal or lateral spikes. Introduced from Eurasia, widespread.

Chenopodium berlandieri – Pitseed Goosefoot

This one is very similar to C. album, and it is extremely difficult to differentiate them in the field. They can only be differentiated by floral morphology & honeycomb-pitted seeds seen at high magnification. Native throughout North America.

Dysphania graveolens aromatic mostly pinnatifid leaves, flowers in compact terminal cymes w leafy bracts that are usu not persistent. Native SW USA and S to Guatemala, Peru, Argentina; of the Amaranthaceae Family

Dysphania graveolens – Fetid Goosefoot

This is an aromatic herb with mostly pinnatifid leaves. Flowers are in compact terminal cymes with leafy bracts that are usually not persistent. Native in southwestern USA south to Guatemala, Peru, and Argentina.

Krascheninnikovia lanata small shrub w flat lanceolate leaves, leaves & stems white-woolly turning reddish. Fruits (utricles) are densely woolly. Endemic to W NAM Canada s to N Mexico; of the Amaranthaceae Family

Krascheninnikovia lanata – Winterfat

This is a small shrub with flat lanceolate leaves. Leaves and stems are both white-woolly turning reddish. Fruits (utricles) are densely woolly, and visible all winter, giving it its common name of Winterfat. Endemic to western North America from Canada south to northern Mexico.

Gomphrenoideae Subfamily

Froelichia floridana annual w 1 erect or ascending stem, leaves on bottom 1/3 plant lanceolate to linear & sericeous-tomentose, flowers in 5 rank pubescent spikes, utricles flask shaped. Native C+E USA, N Mexico; of the Amaranthaceae Family

Froelichia floridana – Large Cottonweed or Plains Snakecotton

A small annual with a single erect or ascending stem leaves on the bottom 1/3 of the plant that are lanceolate to linear & sericeous–tomentose. Flowers are in 5 rank pubescent spikes, and utricles are flask-shaped. Native to central and eastern USA, northern Mexico.

Froelichia gracilis annual to perennial, erect + multi-branched from base, leaves on lower 1/3, often basal. flowers in 3 ranked grey pubescent spikes, utricles conical oblique. Native +E USA, N Mexico; of the Amaranthaceae Family

Froelichia gracilis – Slender Cottonweed

This is an annual to perennial, erect + multi-branched from the base, leaves on the lower 1/3 of the plant, and are often basal. Flowers are in 3 ranked grey pubescent spikes; utricles are conical and oblique. Native to eastern USA and northern Mexico.

Gomphrena serrata erect to prostate perennial/annual, stem pilose, leaves obovate to oblong pilose & sessile to petiolate, flowers in head covered by white lanceolate bracteoles Native SE USA to tropic America; of the Amaranthaceae Family

Gomphrena serrata – Prostrate Globe Amaranth

Is erect to 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 from southeastern USA south to tropical Americas.

Iresine diffusa – Juba’s Bush

This is a branched erect to clambering annual to perennial with ovate–lanceolate leaves that are 3 – 14 cm long and glabrous to villous. Flowers are in villous open panicles (males) or compact panicles (females). Native to South America, introduced into North America.

Salsoideae Subfamily

Halogeton glomeratus highly branched halophytic annual with narrow fleshy blue-green leaves tipped w long spines, flowers in along branch w waxy winged bracts. C Asian intro to W NAM; of the Amaranthaceae Family

Halogeton glomeratus – Salt Lover

This highly branched halophytic annual has narrow fleshy blue-green leaves tipped with long spines. Flowers grow densely along the branches with large conspicuous waxy, winged bracts. Native to central Asia, introduced in western North America.

Salsola kali ssp tragus annual w branched tangled stems, leaves firm linear subulate & usu spine-tipped, flowers w long spiny bracts srnd by disk of winged white/pink sepals. Russian intro; of the Amaranthaceae Family

Salsola kali ssp tragus aka Kali Tragus – Tumbleweed

This is a low-growing annual with branched and tangled stems, firm linear subulate & usually very spine-tipped leaves. Flowers are surrounded by long spiny bracts and a disk of winged white/pink sepals. Widely introduced in western North America, native to Russia. Our most common ‘tumbleweed’.

Taxonomy of Amaranthaceae

There are currently about 2000 – 2500 spp in 180 accepted genera of the Caryophyllales order of core Eudicots. There are currently 10 subfamilies, but this may change. As with all families, current advances in molecular phylogenetics are causing us to re-evaluate family relationships, so this may change in the future as more information is discovered.    

  1. Amaranthoideae – Annual or perennial herbs to shrubs, occasionally small trees.  The inflorescence is branched or not but is usually spike-like or capitate. The bracts are disarticulating, and bracteoles may or may not be papyraceous or scarious. The perianth is typically scarious, and they possess staminodes or pseudostaminodes. Cuticle waxes lack platelets, and hairs are uniseriate. 
  2. Betoideae – Annual to perennial herbs or occasionally subshrubs or vines. Bracteoles are usually present, the perianth has 5 (3) parts and is persistent and accrescent in Beta. The androecium has 5 (1) members, and the gynoecium is sometimes partly inferior. Fruit is a circumscissile capsule or pyxidium.
  3. Camphorosmoideae – Often shrubby plants but sometimes annual herbs, often with C4 photosynthesis, leaves are terete, and ‘prickles’ are often present. Their hairs have swollen bases, styles are filiform with papillae all around. The perianth is fleshy and spiny.
  4. Chenopodioideae – Annual herbs or short-lived perennial herbs to shrubs that are more or less succulent and often have swollen nodes. They prefer dry and 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.
  5. Corispermoideae – Annual herbs without C4 photosynthesis. 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. Perianth has 0-5 membranous tepals that are not persistent.
  6. Gomphrenoideae – Annual to perennial herbs or subshrubs with a perianth that is free to connate. Anthers are bisporangiate, monothecal, and their filaments are more or less connate. Their stigma is either capitate or bilobed.
  7. Polycnemoideae – Annual to perennial herbs or small shrubs that often inhabit saline habitats. Leaves are needle-like or succulent, bracts are disarticulating, and bracteoles are large. Flowers are axillary, the perianth is petaloid but never modified, and the androecium is basally connate. This subfamily is distinguishable from all other members of Amaranthaceae by normal secondary growth. 
  8. Salicornioideae – Annual or perennial herbs to low shrubs, usually with articulated stems. Plants are glabrous, and leaves are usually opposite, more or less terete or scaly or reduced to a rim. The inflorescence is dense, spicate, and leafless. Perianth has 3-4(2-5) parts and is typically at least partially connate. In fruiting, the perianth may remain membranous or become spongy, crustaceous, or horny.
  9. Salsoideae – Herbs, subshrubs, shrubs, or sometimes trees. Stems and leaves are often succulent, leaves are terete, and bracteoles are present. Scarious wings usually develop from the perianth in fruit. Anthers have colored appendages, and their stigmas are flattened.
  10. Suaedoideae – Annual to perennial herbs to shrubs that are usually glabrous and usually have well-developed terete leaves. The inflorescence is spicate axillary cymes that are loose, leafy, and possesses bracteoles. Styles are filiform, stigma may be capitate but is papillate all around. The perianth is persistent and usually accrescent and enlarged or winged when in fruit.

Genera:

Amaranthoideae: Achyranthes (14), Achyropsis (6), Aerva (6, 5 extant), Allmania (1), Allmaniopsis (1), Amaranthus (91 inc Acnida), Arthraerua (1), Bosea (3), Calicorema (2), Celosia (46), Centema (2), Centemopsis (13), Centrostachys (1), Chamissoa (3), Charpentiera (6), Chionothrix (2), Cyathula (28), Cyphocarpa (3 inc Kyphocarpa), Dasysphaera (4), Deeringia (10), Digera (1), Eriostylos (1), Hebanthodes (1), Henonia (1), Herbstia (1), Hermbstaedtia (14), Indobanalia (1), Lagrezia (14), Lecosia (2), Leucosphaera (1), Lopriorea (1), Marcelliopsis (3), Mechowia (2), Nelsia (3), Neocentema (2), Nothosaerva (1), Nototrichium (1), Nyssanthes (4), Omegandra (1), Ouret (8), Pandiaka (13), Paraerva (2), Pleuropetalum (3), Pleuropterantha (3), Polyrhabda (1), Psilotrichopsis (1), Psilotrichum (26), Ptilotus (122), Pupalia (4), Rosifax (1), Saltia (1), Sericocoma (3 inc Pseudosericocoma), Sericocomopsis (2), Sericorema (2), Sericostachys (2), Siamosia (1), Stilbanthus (1), Trichuriella (1), Volkensinia (1), Wadithamnus (1).  

Betoideae: Acroglochin (3), Aphanisma (1), Beta (10), Hablitzia (1), Oreobliton (1), Patellifolia (1).  

Camphorosmoideae: Bassia (22 inc Kirilowia, Kochia, Panderia), Chenolea (2), Didymanthus (1), Dissocarpus (4), Enchylaena (2), Eokochia (1), Eremophea (2), Grubovia (6), Londesia (?), Maireana (59 inc Eriochiton), Malacocera (4), Neobassia (2), Neokochia (2), Osteocarpum (5), Roycea (3), Sclerolaena (78 inc Sclerochlamys, Stelligera), Spirobassia (1), Threlkeldia (2).

Chenopodioideae: Archiatriplex (1), Atriplex (245 inc Cremnophyton, Halimione), Axyris (7), Blitum (10 inc Monolepis, Scleroblitum), Camphorosma (5), Ceratocarpus (1), Chenopodiastrum (8); Chenopodium (129 inc Einadia, Rhagodia), Cycloloma (1), Dysphania (43), Exomis (1), Extriplex (2), Girgensohnia (5), Grayia (4 inc Zuckia), Holmbergia (1), Krascheninnikovia (2), Lipandra (1), Manochlamys (1), Microgynoecium (1), Micromonolepis (1), Neomonolepis (1), Oreosalsola (9) Oxybasis (13), Proatriplex (1), Spinacia (3), Stutzia (2 inc Endolepis), Suckleya (1), Teloxys (1). 

Corispermoideae: Agriophyllum (6), Anthochlamys (5), Corispermum (68). 

Gomphrenoideae: Alternanthera (113), Blutaparon (4, 3 extant), Froelichia (15), Froelichiella (1), Gomphrena (129 inc Philoxerus, Pseudogomphrena), Guilleminea (8 inc Brayulinea, Gossypianthus), Hebanthe (6), Iresine (34 inc Dicaurus, Irenella, Woehleria), Lithophila (2), Pedersenia (8), Pfaffia (33), Pseudoplantago (2), Quaternella (3), Tidestromia (6), Xerosiphon (2).

Polycnemoideae: Hemichroa (1), Nitrophila (4), Polycnemum (6), Surreya (2).

Salicornioideae: Allenrolfea (3), Arthrocaulon (2), Arthroceras (1), Halocnemum (2), Halopeplis (3), Halostachys (1), Heterostachys (2), Kalidium (7), Mangleticornia (1), Microcnemum (1), Salicornia (52 inc Arthrocnemum, Sarcocornia), Tecticornia (45 inc Halosarcia, Pachycornia, Sclerostegia, Tegicornia). 

Salsoideae: Agathophora (1), Anabasis (30 inc Fredolia), Arthrophytum (8), Caroxylon (128), Climacoptera (40), Cornulaca (6), Cyathobasis (1), Gamanthus (5), Halanthium (5), Halarchon (1), Halimocnemis (16), Halocharis (6), Halogeton (3), Halothamnus (22 inc Aellenia), Haloxylon (11), Hammada (2), Horaninovia (7), Iljinia (1), Kaviria (9), Lagenantha (2), Nanophyton (8), Noaea (6), Nucularia (1), Ofaiston (1), Petrosimonia (11), Piptoptera (1), Pyankovia (3), Rhaphidophyton (1), Salsola (64 inc Kali, Physandra), Seidlitzia (3), Soda (2), Sympegma (2), Traganopsis (1), Traganum (2), Turania (4), Xylosalsola (4).

Suaedoideae: Baolia (1), Bienertia (4), Fadenia (1), Sevada (1), Suaeda (91 inc Alexandra, Borsczowia). 

Key Differences From Similar Families

Amaranthaceae differs from the similar but very small (only two genera) Achatocarpaceae family because Amaranthaceae usually have a herbaceous habit vs always woody and always with normal secondary growth in the Achatocarpaceae. Amaranthaceae also usually have dry fruits rather than the succulent berries found in the Achatocarpaceae.  

Distribution of Amaranthaceae

Temperate to tropical, a truly cosmopolitan family missing only from Antarctica and the most extreme Arctic areas. Widespread through all of the Americas., Mexico, Central America, the Caribbean, and South America.  

Distribution of Amaranthaceae in the Americas

Canadian Genera Include:

Amaranthoideae: Achyranthes 1 of 14 Old World Tropics spp intro ON; Amaranthus 20 of 91 cosmopolitan spp intro BC, NT, NB, NS, PE, NL Island, native AB, SK, MB, ON, QC. Camphorosmoideae: Bassia 2 of 22 Old World & USA spp intro to all S provinces exc NL, NS, PE. Chenopodioideae: Atriplex 18 of 245 cosmopolitan spp native all of Canada (inc GL) but exc NU?; Axyris 1 of 7 Asian spp intro all of S Canada exc PE, NL; Blitum 4 of 10 mostly N temperate spp inc 2 spp native and 2 spp intro in all of Canada inc Arctic but ephemeral PE, NL (exc Labrador); Chenopodiastrum 4 of 8 N temperate & subtropical spp inc 1 sp native all S provinces exc NL, and 3 spp intro S Canada and YT, NT, absent NU; Chenopodium 19 of 129 cosmopolitan spp native YT, NT, BC, AB, SK, MB, ON, QC, NS, intro in NB, PE, NL, NU (and GL); Cycloloma monospecific former C NAM endemic sp native SK, MB, ON, intro QC, Argentina, Europe; Dysphania 3 of 43 subcosmopolitan spp intro BC, ON, QC, NB, NS; Krascheninnikovia 1 of 2 N temperate spp native YT, AB, SK, MB; Lipandra monospecific Eurasian sp intro BC, SK, MB, ON, QC, NB; Oxybasis 6 of 13 subcosmopolitan spp inc 3 spp native all of Canada inc Arctic exc PE, NL, and 3 spp intro E Canada; Spinacia 1 of 3 WC Asian spp ephemeral YT, NT, AB, MB, plus cultivated Spinacia; Stutzia 1 of 2 NW NAM endemic spp native AB, SK; Suckleya monospecific N-C NAM endemic sp native to AB, SK. Corispermoideae: Corispermum 6 of 68 temperate & subtropical N hemisphere spp intro QC, native BC, AB, SK, MB, ON, QC, YT, NT.  Gomphrenoideae: Froelichia 1 of 15 former Americas endemic spp intro ON. Polycnemoideae: Polycnemum 3 of 6 Europe + C Asia spp intro BC, ON. Salicornioideae: Salicornia 5 of 52 cosmopolitan spp native to all of Canada exc Labrador, in coastal and inland saline areas. Salsoideae: Salsola (inc Kali) 3 of 64 mostly Eurasian spp intro all S provinces. Suaedoideae: Suaeda 4 of 91 cosmopolitan spp native all of Canada exc Labrador.

USA Genera Include:

Amaranthoideae:Achyranthes 4  of 14 Old World Tropics spp intro TX, LA, FL, AL, KY, WV, IN, OH, MD, native and intro HI, inc 2 spp endemic to HI; Aerva 1 of 6 mostly Old World Tropics spp native and believed extinct in HI; Amaranthus 45 of 91 cosmopolitan spp intro and native in all USA inc HI, intro AK; Celosia 4 of 46 almost pantropical spp inc 1?? native TX, FL and 3 spp intro 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 of 6 Pacific Islands spp endemic to HI; Digera monospecific Old World Tropics sp intro NJ; Hermbstaedtia 1 of 14 African spp sp intro MD; Nototrichium monospecific endemic HI. Betoideae: Aphanisma monospecific SW NAM endemic sp native CA; Beta 2 of 10 Eurasian spp intro MT, OR, CA, UT, TX, MO, AL, SC, NC, VA, WV, PA, MI, NY, CT, MA, RI, NH, ME. Camphorosmoideae: Bassia 6 of 22 Old World & USA spp inc 2 spp native and 4 spp intro most USA exc AR, GA, FL, native TX, intro HI; Enchylaena 1 of 2 Australian spp intro CA; Neokochia 2 of 2 W USA endemic spp of OR, CA, ID, NV, MT, WY, CO, UT, AZ, NM, TX; Spirobassia monospecific Eurasian spp intro PA, NJ, MD, NY, CT. Chenopodioideae: Atriplex 94 of 245 cosmopolitan spp native and intro most USA inc AK, exc AR, TN and intro HI; Axyris 1 of 7 Asian spp intro MT, CO, ND, WI, MO; Blitum (inc Monolepis) 4 of 10 mostly N temperate spp inc 3 spp native and 1 sp intro most of USA exc AR S to LA and E to NC S to FL plus VA, MD, DE, inc 1 narrow endemic of CA + Baja California Mexico; Chenopodiastrum 2 of 8 N temperate & subtropical spp inc 1 sp native most of USA inc AK exc OR, AZ, AL, GA, SC, FL where intro and 1 sp intro scattered throughout USA; Chenopodium 41 of 129 cosmopolitan spp (may inc Oxybasis) native and intro all USA inc AK and HI; Cycloloma monospecific former C NAM endemic sp native most of USA exc WA, OR, GA, FL, VT, NH, ME, now intro Argentina, Europe; Dysphania 11 of 43 subcosmopolitan spp native and intro entire USA, intro AK, HI, mosty native in S USA, mostly intro N USA; Stutzia (inc Endolepis) 2 of 2 NW NAM endemic spp native CA, NV, MT, WY, CO, ND, SD, NE; Extriplex 2 of 2 SW NAM endemic spp native CA, inc 1 narrow endemic of CA, other sp also native Baja California Mexico; Grayia (inc Zuckia) 4 of 4 W USA endemic spp from MT S to NM and all W; Krascheninnikovia 1 of 2 N temperate spp native W USA from ND S to TX and all states W; Lipandra monospecific Eurasian sp intro OR, WI, IL, MI, PA, NJ, NY, CT, ME; Micromonolepis monospecific W USA endemic of WA, OR, CA, NV, UT, CO, WY; Neomonolepis monospecific former SW NAM endemic of CA, NV, OR, now intro Australia; Oxybasis 6 of 13 subcosmopolitan spp native inc 2-3 spp native in most of USA exc the SE states and 2-3 spp intro in all of USA inc FL, AL, IL, IN, KY, WV, VA,NC,VT; Proatriplex monospecific S-C USA endemic of UT, AZ, CO, NM; Spinacia 1 of 3 WC Asia sp intro WA, OR, CA, UT, TX, KS, SC, NC, VA, OH, PA, CT, MA, NY, NH, ME, plus cultivated Spinacia; Suckleya monospecific N-C NAM endemic sp native MT, ND, WY, CO, NM, AZ, NE, OK, TX; Teloxys monospecific Asian sp intro MI, NY and AK. Corispermoideae: Corispermum 9 of 68 temperate & subtropical N hemisphere spp native and intro most USA exc ME, VT, NH, PA, MD, DE, WV, VA, TN, NC, SC, LA, MS, AL, FL, native AK, extirpated or extinct CA. Gomphrenoideae: Alternanthera 11 of 113 mostly pantropical spp inc 1 sp native FL and the rest intro CA, AZ, NM, TX, OK, MO, AR, LA, IL, KY, TN, MS, AL, GA, SC, NC, VA, MD, PA, NJ, NY and HI; Blutaparon 1 of 4 Americas, Africa & Japan spp native TX, LA, FL; Froelichia 6 of 15 former Americas endemic spp native most USA exc WA, OR, ID, MT, NV, UT, ND, VT, RI, ME, inc 2 narrow endemics of TX, intro CA?, now intro Australia, Japan; Gomphrena 8 of 129 now pantropical spp native AZ, NM, TX, LA, FL, GA, VA, and intro PA, MD, OH, NY, MA and HI; Guilleminea (inc Gossypianthus) 1 of 8 former Americas endemic spp native CA, AZ, NM, TX, OK, CO, SC, MD, AR, LA, genus now intro Africa, Australia; Iresine 6 of 34 former Americas endemic spp native AZ, NM, TX, KS, OK, MO, AR, LA, IL, IN, KY, TN, MS, AL, GA, FL, SC, NC, MD, PA, intro HI & pantropical; Tidestromia 5 of 6 NAM & Caribbean endemic spp native CA, NV, UT, AZ, CO, NM, TX, LA, OK, KS, SD, MO, IL, PA. Polycnemoideae: Nitrophila 2 of 4 Americas endemic spp native WA, OR, CA, NV, UT, AZ, inc 1 narrow endemic of Mohave desert of SE CA + SW NV, other 2 spp endemic C+S SAM; Polycnemum 1 of 6 Europe & C Asia spp intro IN, NY, MD, DE, NH. Salicornioideae: Allenrolfea 1 of 3 Americas endemic spp is a SW NAM endemic native to OR, ID, CA, NV, UT, AZ, NM, TX, other 2 spp endemic Argentina; Arthroceras monospecific SW NAM endemic sp native CA; Salicornia (inc Arthrocnemum) 5 of 52 cosmopolitan spp native most of USA inc AK but exc AZ, OK, AR, TN, KY, IN, WI, WV, PA, VT, intro in HI, MI, extirpated IL, found in coastal & inland saline areas. Salsoideae: Caroxylon 1 of 128 African & Eurasian  spp intro CA; Halogeton 1 of 3 Mediterranean & W Asian spp intro in all W USA MT S to NM and all W, inc SD, NE; Salsola 6 of 64 mostly Eurasian spp intro all of USA inc HI; Soda 1 of 2 Mediterranean spp intro CA. Suaedoideae: Suaeda 13 of 91 cosmopolitan spp intro and native most of USA exc IA, AR, TN, WV, VT, native AK.

Mexico Genera Include:

Amaranthoideae: Achyranthes 1 of 14 Old World Tropics spp intro all of Mexico; Amaranthus ?? of 91 cosmopolitan spp native through all of Mexico and intro to Mexican Pacific Is; Celosia ?? of 46 almost pantropical spp native most of Mexico exc Mex, Cd Mex, Tlx, Mor where it is intro; Chamissoa 1 of 3 Mexico & Neo endemic spp native in all of Mexico; Cyathula 1 of 28 pantropical spp native Nay, Jal, Col, Gro, Mch, Oax, Chp, Pue, Ver, Tab, Cam, QR, Yuc; Lagrezia 1 of 14 otherwise mostly Madagascar endemic spp endemic to Mexico in Nay, Jal, Col, Mch, Gro, Oax, Chp, Tab, Cam, Yuc, QR; Pleuropetalum 2 of 3 Mexico & Neo endemic spp native N+SE+SE Mexico, Ver. Betoideae: Aphanisma monospecific SW NAM endemic sp native BC, BCS?, Mexican Pacific Is; Beta 2 of 10 Eurasian spp intro BC, BCS, Son, Sin. Camphorosmoideae: Bassia ?? of 22 Old World & USA spp intro BC, BCS, Son?, Sin?. Chenopodioideae: Atriplex ?? of 245 cosmopolitan spp native through all of Mexico inc Mexican Pacific Is; Blitum 4 of 10 mostly N temperate spp inc 2 spp native and 2 spp intro N Mexico BCN, BCS, Son, Sin, Chi, NL, Tam, Dgo, Zac, SLP, Gto, Qro?, Hgo?, inc 1 narrow endemic of BC and California USA; Chenopodiastrum 1 of 8 N temperate & subtropical spp intro BC, BCS, Son, Sin, Nay, Jal, Col, Mch, Gro, Oax; Chenopodium ?? of 129 cosmopolitan spp native throughout all of Mexico; Cycloloma monospecific former C NAM endemic sp native Chi, Dgo, Zac, SLP, Hgo, Gto, Qro, NL, Tam, Coa, now intro Argentina, Europe; Dysphania ?? of 43 subcosmopolitan spp native all of Mexico, intro Mexican Pacific Is; Extriplex 2 of 2 SW NAM endemic spp native BCN, BCS?; Krascheninnikovia 1 of 2 mostly N temperate spp native N Mexico BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Qro, Ags, Gto, SLP; Neomonolepis monospecific former SW NAM endemic native BCN, BCS?, now intro Australia; Oxybasis 4 of 13 subcosmopolitan spp inc 2 spp native Chi, Coa, NL, Tam, Dgo, Zac, Ags, SLP, Gto, Qro, Hgo, Mex, Cd Mex, Mor, Nay, Jal, Col, Gro, Mch, Oax, and 2 spp intro BC, BCS, Son, Sin, inc 1 sp endemic to most of Mexico. Corispermoideae: Corispermum ?? of 68 temperate & subtropical N hemisphere spp native Chi, Dgo, Zac, SLP, Hgo, Gto, Qro, NL, Tam, Coa. Gomphrenoideae: Alternanthera ?? of 113 mostly pantropical spp native throughout all of Mexico; Blutaparon 1 of 4 Americas, Africa & Japan spp native most of Mexico exc C Mexico; Froelichia 6 of 15 former Americas endemic spp native in all of Mexico, inc 1 narrow endemic of BCS, the genus now intro Japan, Australia; Gomphrena ?? of 129 now pantropical spp native all of Mexico; Guilleminea 2 of 8 former Americas endemic spp native N+SW+C Mexico, now intro Australia, Africa; Hebanthe 1 of 6 Mexico & Neo endemic spp native Chi, Coa, NL, Tam, Dgo, Zac, Gto, SLP, Qro, Nay, Jal, Col, Gro, Mch, Oax, Ver, Tab, Cam, Yuc, QR; Iresine ?? of 34 former Americas endemic spp native all of Mexico; Pfaffia ?? of 33 Neo endemic spp native S Mexico in Nay, Jal, Col, Mch, Gro, Oax, Chp, Cam, Tab, QR, Yuc; Tidestromia 6 of 6 NAM & Caribbean endemic spp native N Mexico BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Gto, Qro, SLP, Hgo, Ags, inc 1 narrow endemic of Coa. Polycnemoideae: Nitrophila 1 of 4 Americas endemic spp native NW Mexico. Salicornioideae: Allenrolfea 1 of 3 Americas endemic spp is a SW NAM endemic native to BCN, BCS, Son, Sin, Chi, NL, Tam, Dgo, SLP, other 2 spp endemic Argentina; Arthroceras monospecific SW NAM endemic sp native BC, BCS, Son?, Sin?; Salicornia ?? of 52 cosmopolitan spp native most of Mexico exc Pue, coastal & inland saline areas. Salsoideae: Salsola ?? of 64 mostly Eurasian intro BC, BCS, Son, Sin, Chi, Coa, NL, Tam, Dgo, Zac, Gto, Qro, Ags. Suaedoideae: Suaeda ?? of 91 cosmopolitan spp native in all of Mexico inc Mexican Pacific Is.

Neotropical Genera Include:

Amaranthoideae: Achyranthes 1 of 14 Old World Tropics spp intro CAM (exc Costa Rica), Bahamas, Turks-Caicos, Aruba, Antilles (exc Cayman Is), SW Caribbean, Galapagos, tropical SAM S to Peru, Bolivia, C+SE Brazil (exc Ecuador); Amaranthus ?? of 91 cosmopolitan spp native throughout N Caribbean, Antilles, SW Caribbean, Trinidad-Tobago, CAM, all of SAM, Galapagos, intro Bermuda, Juan Fernandez Is; Celosia ?? of 46 almost pantropical spp native Guatemala, El Salvador, Honduras, Nicaragua, Panama, Cuba, Hispaniola, Puerto Rico, Bahamas, Leeward & Windward Is, Venezuela, Colombia, Ecuador, Peru, N+E+S Brazil, intro Belize, Cayman Is, Galapagos, Trinidad-Tobago, C Brazil, Bolivia, NE Argentina, Paraguay; Chamissoa 3 of 3 Mexico & Neo endemic spp native Greater Antilles (exc Cayman Is), CAM S through tropical SAM to N Argentina exc French Guiana, N Chile, inc 2 spp endemic to SAM; Cyathula 3 of 28 pantropical spp inc 2 spp native CAM, Cuba, Hispaniola, Jamaica, Trinidad-Tobago, Colombia, Venezuela, Brazil, Ecuador, Peru, Bolivia, and 1 sp intro 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, NE Argentina; Lecosia 2 of 2 narrow endemic spp of E Brazil; Pleuropetalum 3 of 3 Mexico & Neo endemic spp native CAM, Venezuela, Colombia. Ecuador, Peru, Bolivia, Galapagos, inc 1 narrow endemic of Galapagos. Betoideae: Beta 2 of 10 Eurasian spp intro Honduras, Cuba, Cayman Is, Dominican Republic, Puerto Rico, Ecuador, N+C Chile, Juan Fernández Is, Argentina, Uruguay. Camphorosmoideae: Bassia 1 of 22 Old World & USA spp intro C Chile, Argentina; Maireana 1 of 59 Australian spp intro N Chile, Desventurados Is; Chenopodioideae: Atriplex ?? of 245 cosmopolitan spp native Honduras, Bermuda, Antilles (exc Windward Is), SW Caribbean, Venezuela, Colombia, Peru, Bolivia, Paraguay, Chile, Argentina, Uruguay S Brazil; Blitum 1 of 10 mostly N temperate spp intro Argentina; Chenopodiastrum 1 of 8 N temperate & subtropical spp intro Honduras, Nicaragua, Panama, Bermuda, Bahamas, Turks-Caicos, Antilles (exc Cayman Is, Windward Is), Venezuela, Colombia, Ecuador, Peru, Bolivia, C+E Brazil, Chile, N Argentina, Uruguay; Chenopodium ?? of 129 cosmopolitan spp native Honduras, Panama, Colombia, Ecuador, Peru, Chile, Argentina, Paraguay, S Brazil, intro C+E Brazil, Bermuda, Bahamas, Cuba, Dominican Republic, Trinidad-Tobago; Cycloloma monospecific former C NAM endemic sp intro NE Argentina; Dysphania ?? of 43 subcosmopolitan spp native CAM (exc Costa Rica), Bermuda, all of SAM exc Ecuador, French Guiana, Suriname, Guyana where intro, also intro Bahamas, Antilles, SW Caribbean, Trinidad-Tobago, Galapagos, Juan Fernandez Is; Holmbergia monospecific C SAM endemic of Bolivia, Paraguay, Uruguay, N Argentina; Oxybasis 5 of 13 subcosmopolitan spp inc 3 spp native Peru, Bolivia, Chile, NW+S Argentina and 2 spp intro Argentina, inc 2 narrow endemics of W + S Argentina (1), S Chile + S Argentina (1); Spinacia oleracea cultivated spinach, intro Hispaniola, Cayman Is. Gomphrenoideae: Alternanthera ?? of 113 mostly pantropical spp Bermuda, Bahamas, Turks-Caicos, Aruba, Antilles, CAM and and all of SAM inc Galapagos exc S Chile; Blutaparon 3 of 4 Americas, Africa & Japan spp native Belize, Honduras, Nicaragua, Panama, Bahamas, Antilles, Trinidad-Tobago, Ecuador, Colombia, Venezuela, Guyana, Suriname,French Guiana, N+E+S Brazil, NE Argentina, Uruguay, inc 1 sp endemic to SAM, 1 endemic and extinct sp of Galapagos; Froelichia 8 of 15 former Americas spp native to Americas Guatemala, Honduras, Nicaragua, Cuba, Hispaniola, Jamaica, Colombia, Venezuela, Brazil, Ecuador, Galapagos, Peru, Bolivia, Paraguay, Uruguay, N Argentina, inc 4 narrow endemics of Galapagos (2), Para N Brazil (1), Paraguay (1); Froelichiella monospecific endemic C Brazil; Gomphrena ?? of 129 now pantropical spp native CAM, most of SAM exc Suriname, French Guiana, S Chile, intro Greater Antilles, Trinidad-Tobago, Venezuelan Antilles; Guilleminea 4 of 8 former Americas endemic spp native Cuba, Hispaniola, Colombia, Ecuador, Peru, Bolivia, C Brazil, Paraguay, N Argentina, Uruguay, inc 2 narrow endemics of Cuba (1), Uruguay (1); Hebanthe 6 of 6 Mexico & Neo endemic spp native CAM (exc El Salvador), tropical SAM S to N Argentina exc N Chile, Uruguay, Guyana, Suriname, inc 3 spp endemic to Brazil; Iresine 34 of 34 former Americas endemic spp native from S USA, Mexico, Bahamas, Antilles (exc Aruba, Netherlands Antilles), CAM S through tropical SAM to N Argentina (exc French Guiana, N Chile), 1 sp now intro pantropical; Lithophila 2 of 2 Neo endemic spp native Bahamas, Turks-Caicos, Cayman Is., Cuba, Dominican Republic, Puerto Rico, Lesser Antilles, Trinidad-Tobago, Galápagos, Suriname, Venezuela, inc 1 narrow endemic of Galapagos; Pedersenia 8 of 8 Neo endemic spp of Honduras S to Colombia, Venezuela, Ecuador, Peru, Paraguay, N Brazil, plus Puerto Rico, Windward Is; Pfaffia 33 of 33 Neo endemic spp native from S Mexico, Haiti, Leeward & Windward Is, Venezuelan Antilles, Trinidad-Tobago, tropical SAM S to N Argentina (exc N Chile); Pseudoplantago 2 of 2 SAM endemic spp endemic to Venezuela (1), S Brazil + NE Argentina (1); Quaternella 3 of 3 spp endemic to C+E+S Brazil; Tidestromia 1 of 6 NAM & Caribbean endemic spp native Dominican Republic; Xerosiphon 2 of 2 spp endemic to N+C+E Brazil. Polycnemoideae: Nitrophila 2 of 4 Americas endemic spp native Argentina, N Chile, with 1 sp endemic to each Antofagasta N Chile (1) and Argentina (1); Salicornioideae: Allenrolfea 2 of 3 Americas endemic spp are endemic to Argentina, other sp is endemic to SW NAM; Heterostachys 2 of 2 Neo & SAM endemic spp native Hispaniola, Colombia, Venezuela, Paraguay, Argentina, inc 1 narrow endemic of Buenos Aires, Mendoza & Rio Negro Argentina at N limit of Patagonia; Mangleticornia monospecific endemic of Ecuador, Peru; Salicornia ?? of 52 cosmopolitan spp native in coastal and inland saline areas of Bahamas, Turks-Caicos, Antilles (exc Windward Is), Colombia, Venezuela, Ecuador, Peru, Bolivia, Paraguay, S Brazil, Argentina, Chile, Uruguay. Salsoideae:  Salsola ?? of 64 mostly Eurasian intro Uruguay, C+S Chile, Argentina; Soda 1 of 2 Mediterranean spp intro NE Argentina. Suaedoideae: Suaeda ?? of 91 cosmopolitan spp native Bahamas, Turks-Caicos, Cuba, Hispaniola, Leeward Is, Peru, Bolivia, Chile, Argentina, and extinct or extirpated Juan Fernandez Is.

Patagonia Genera Include:

Amaranthoideae: Amaranthus 4 of 91 cosmopolitan spp native C+S Argentina, C+S Chile. Betoideae: Beta 1 of 10 Eurasian spp intro C Chile, S Argentina. Camphorosmoideae: Bassia 1 of 22 Old World & USA spp intro C Chile, S Argentina. Chenopodioideae: Atriplex 1 of 245 cosmopolitan spp native throughout Patagonia and intro Falkland Islands; Blitum 1 of 10 mostly N temperate spp intro S Argentina; Chenopodiastrum 1 of 8 N temperate & subtropical spp intro C+S Chile; Chenopodium 1 of 129 cosmopolitan spp native Patagonia; Dysphania 1 of 43 subcosmopolitan spp native Patagonia; Oxybasis 4 of 13 subcosmopolitan spp inc 3 spp native C+S Chile, S Argentina, Falkland Islands and 1 sp intro Patagonia. Gomphrenoideae: Alternanthera 1 of 113 mostly pantropical spp native just N of Patagonia in the mountains N of Bahia Blanca, S Argentina; Gomphrena ?? of 129 now pantropical spp native S Argentina. Polycnemoideae: Nitrophila 1 of 4 Americas endemic spp native S Argentina near N limit of Patagonia. Salicornioideae: Allenrolfea 1 of 3 Americas endemic spp is endemic to Argentina inc S Argentina; Heterostachys 1 of 2 Neo & SAM endemic spp a narrow endemic of Buenos Aires, Mendoza & Rio Negro Argentina at N limit of Patagonia; Salicornia ?? of 52 cosmopolitan spp native throughout Patagonia in salt marshes and lagoons. Salsoideae: Salsola ?? of 64 mostly Eurasian intro Patagonia. Suaedoideae: Suaeda 1 of 91 cosmopolitan spp native Patagonia inc Falkland 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 (2022).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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/
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

25 Sep, 2022

18 Sep, 2022

Identify the Anacardiaceae Cashew or Sumac Family

Rhus typhina with its imparipinnate leaves and hairy red drupes in dense panicles, typical of the Anacardiaceae family.
Rhus typhina with its imparipinnate leaves and hairy red drupes in dense panicles, is typical of the Anacardiaceae family.

Table of contents

Introduction to the Anacardiaceae Family

The Anacardiaceae family is part of the Sapindales Order of core Eudicots. The Anacardiaceae family is well known for the various species of Sumac (Rhus spp) and Poison Ivies (Toxicodendron spp) that we have throughout North America. The Sumac trees are often used ornamentally for their ease of growing and their pretty red drupes that persist all winter. Poison Ivy is well known to anyone who has ever hiked in the forest since it causes very itchy contact dermatitis. 

There is an old saying, “leaves of three let it be” since all of 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 a poison ivy. Poison ivy (shrub forms) can also be mistaken for young oaks at times because the leaves often resemble those of the White Oak.

Flowers of the Anacardiaceae

Plants can be hermaphrodite, monoecious, dioecious, gynodioecious, or polygamomonoecious. Pollination when heterantherous is entomophilous.  Flowers are aggregated in racemose panicles. Flowers are small, regular, usually 5 merous, and either tetracyclic or pentacyclic. Free hypanthium is either absent or present but short. A hypogynous disk is present, intrastaminal and annular. The perianth has a distinct calyx and corolla or may be sepaline. The perianth has 3–5 or 6–10 parts in 1 or 2 whorls and is isomerous. Calyx has 3–5 parts in 1 whorl, is basally connate, often with cleft sepals, and lobes are shorter to longer than the tube. The calyx is regular and imbricate. The corolla, when present, has 3–5 parts in 1 whorl, is usually free but rarely can be connate basally, the lobes are longer than the tube, and it is imbricate.

Androecium of the Anacardiaceae

The androecium has 5–10(11–12) parts. Androecial members are free of the perianth and may be free of one another or coherent 1 adelphous (the filaments are sometimes basally connate). The members may be all equal or unequal and can be either 1 or 2 whorled. Androecium may or may not include staminodes. When present, there are 1-9 staminodes. There are 5–10(1–12) stamens, they are oppositisepalous, inserted at the base of the hypogynous disc, and are usually equal in number or twice as many as the petals. Anthers are usually dorsifixed or sometimes basifixed (Spondias), they are versatile, dehiscing via longitudinal slits, introrse, and tetrasporangiate.

Gynoecium of the Anacardiaceae

The gynoecium is usually 5 carpelled but can be 1–6 carpelled, and the pistil is 1–5 celled. The gynoecium is synovarious or synstylovarious, or rarely semicarpous. It is usually superior or sometimes partly inferior. The ovary is 1–5 locular. There is usually one style, but there may be 3–6 styles, and in Buchanania, it has up to five styles from sterile carpels. There are 1-5 stigmas, they are wet type, non-papillate, and Group IV type. Placentation, when unilocular, is parietal or basal, and when bi- or plurilocular, it is basal. There is 1 ovule per locule, it is pendulous or ascending, has either ventral or dorsal raphe, is non-arillate, anatropous, unitegmic or bitegmic, and crassinucellate. 

Fruit of the Anacardiaceae

The fruit is usually a fleshy drupe, but sometimes it is an indehiscent non-fleshy dry fruit. The drupes have one stone, rarely open at maturity, and sometimes contain urushiol, a toxic irritant found in poison ivy and other species. Seeds are non-endospermic.

Habit & Leaf Form of the Anacardiaceae

Trees or shrubs, self-supporting or climbing, sometimes with a milky juice that may be resinous or laticiferous. Leaves are persistent or deciduous, alternate spiral except in Bouea, where they are opposite, herbaceous, and aromatic when resinous but otherwise odorless. They are simple or compound ternate, trifoliate, imparipinnate, or rarely paripinnate or bipinnate. Primary venation is pinnate or rarely palmate. Secondary venation is eucamptodromous, brochidodromous, craspedodromous, cladodromous, or rarely reticulodromous.  If present, cladodromous venation is diagnostic for the Anacardiaceae family. Leaves are exstipulate. Lamina margins are entire. Domatia occur in 8 genera as pits, pockets, or hair tufts. 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.

Uses of 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), 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 Toxicodendron spp. (Poison Oak, Poison Ivies).

Morphology of Anacardiaceae in North America

Female flower of Rhus aromatica; 1 style and 1 stigma, superior ovary, features common in Anacardiaceae.
Female flower of Rhus aromatica; 1 style and 1 stigma, superior ovary, features common in Anacardiaceae.
Male flowers of Rhus aromatica, when dioecious the male flowers of Anacardiaceae are often catkins
Male flowers of Rhus aromatica, when dioecious the male flowers of Anacardiaceae are often catkins
Dense panicles of hairy red drupes of Rhus typhina; hairy red drupes are common in Anacardiaceae
Dense panicles of hairy red drupes of Rhus typhina; hairy red drupes are common in Anacardiaceae
Imparipinnate (odd # leaves) of Rhus glabra, one of the two most common leaf types of Anacardiaceae in North America.
Imparipinnate (odd # leaves) of Rhus glabra, one of the two most common leaf types of Anacardiaceae in North America.
Trifoliate leaves Tocicodendron radicoans, one of the two most common leaf types of Anacardiaceae in North America.
Trifoliate leaves Tocicodendron radicoans, one of the two most common leaf types of Anacardiaceae in North America.
Flowers of Rhus microphylla - Anacardiaceae flowers are typical quite small and densely packed in racemose panicles
Flowers of Rhus microphylla – Anacardiaceae flowers are typical quite small and densely packed in racemose panicles

Anacardiaceae Species I have Covered So Far

Anacardioideae Subfamily

Mangifera indica Mango tree 10-20m tall with long oblong leaves & large edible fruits, Asian but cultivated in North America. Part of the Anacardiaceae family.

Mangifera indica – Mango

A 10 – 20m tall tree with long oblong leaves and large edible drupes fruits on very long peduncles. Native to Asia but widely cultivated in southern North America, especially in Mexico.

Rhus aromatica Fragrant Sumac malodorous shrub with trifoliate lobed leaves & cluster of hairy red berries. Native to USA, Mexico, SE Canada. Part of the Anacardiaceae family.

Rhus aromatica – Fragrant Sumac

A somewhat lemon-scented shrub with trifoliate lobed leaves and hairy red drupes. Dioecious with small inconspicuous flowers. Native throughout USA, Mexico, and southeastern Canada.

Rhus copallinum Shining Sumac shrub shiny pinnate leaves that have winged rachis or petiolules. Native to E North America, often cultivated. Part of the Anacardiaceae family.

Rhus copallinum – Shining Sumac

A tall shrub with glossy odd-pinnate leaves that have a conspicuously winged rachis or petiolules. Native to eastern North America, often cultivated.

Rhus glabra Smooth Sumac shrub, hairless branches, pinnate leaves 11-31 acuminate serrated leaflets; lg dense panicles of red berries. Native E NAM, sporadic in W NAM. Part of the Anacardiaceae family.

Rhus glabra – Smooth Sumac

A tall shrub with hairless branches and odd-pinnate leaves with 11 – 31 acuminate serrated leaflets. Produces large dense panicles of red drupes. Native to eastern North America with scattered populations in western North America.

Rhus microphylla Littleleaf Sumac a desert shrub that often flowers without its small hairy pinnate leaves; fruits clusters of small hairy berries. Native SW USA plus N + Central Mexico. Part of the Anacardiaceae family.

Rhus microphylla – Littleleaf Sumac

A desert shrub that often flowers before its tiny odd-pinnate glossy green, leathery, hairy leaves emerge. Fruits are clusters of small hairy drupes. Native to southwestern USA plus north and central Mexico.

Rhus trilobata Skunkbush Sumac shrub trifoliate lobed leaves, catkin flowers, fruits hairy sticky red berries. Pungent bitter scent. Native W NAM inc Mexico. not found in the east. Part of the Anacardiaceae family.

Rhus trilobata – Skunkbush Sumac

Gets a bad rap for its pungent bitter scent, but it is not as unpleasant as a skunk. It is a shrub with trifoliate lobed leaves, and flowers in catkins, and its fruits are hairy sticky red drupes. Native to western North America, including western Mexico.

Rhus typhina Staghorn Sumac shrub pinnate leaves 9-31 serrate leaflets, stems & petioles are densely red-hairy (unlike R. glabra) Native NE USA & SE Canada. Part of the Anacardiaceae family.

Rhus typhina – Staghorn Sumac

A large shrub with odd-pinnate leaves with 9 – 31 serrated leaflets; stems and petioles are densely red-hairy (unlike R. glabra). Native to northeastern USA and southeastern Canada.

Searsia lancea African Sumac or Willow Rhus, introduced from Africa, cultivated in S USA & Mexico. Narrow willow-like leaves. Part of the Anacardiaceae family.

Searsia lancea – African Sumac or Willow Rhus

Tree from Africa with pendulous twigs and narrow willow-like leaves. Occasionally cultivated in the southern USA and Mexico.

Toxicodendron pubescens shrub to 1m with variable trifoliate alternate pubescent leaves, causes contact dermatitis. Native SE USA W to OK & TX. Part of the Anacardiaceae family.

Toxicodendron pubescens – Atlantic Poison Oak

A perennial shrub to 1 m tall with variable trifoliate alternate pubescent leaves that are often irregularly lobed. Causes contact dermatitis. Native to southeastern USA west to OK and TX.

Toxicodendron radicans vine (can be shrub) with woody stems & trifoliate shiny leaves usually not serrated; grey-white drupes. Causes contact dermatitis. Native E USA & Canada, not found in the west. Part of the Anacardiaceae family.

Toxicodendron radicans – Eastern Poison Ivy

A climbing vine (sometimes a shrub) with woody stems & trifoliate shiny leaves that are usually not serrated. Flowers are small greenish, and inconspicuous. The fruit is a gray-white drupe. Causes contact dermatitis. Native to eastern USA and Canada.

oxicodendron rydbergii Western Poison Ivy is a shrub with trifoliate leaves, its 2 opposite leaves often asymmetrical. White, yellow or brown drupes are ribbed. Native all USA & Canada but mostly western. Part of the Anacardiaceae family.

Toxicodendron rydbergii – Western Poison Ivy

A shrub with opposite trifoliate leaves that are often asymmetrical. The fruits are white, yellow, or brown drupes that are ribbed. Native throughout USA and Canada but mostly found in the west.

Taxonomy of the Anacardiaceae Family

The Anacardiaceae has about 938 spp in 79 genera of the Sapindales Order of core Eudicots. There are two accepted subfamilies with several dissident genera in their own groups or unplaced, here I have put them all as “unplaced in a subfamily.” As APG updates these, this record will be updated to reflect any changes.

  1. Anacardioideae – Trees or shrubs with black or colored resinous exudate and crystals are present in the xylem. Leaflets are not articulated, margins are usually entire, 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 carpelled, and the stigma is dry and capitate or lobed. The fruit is a drupe that is layered with a crystalliferous endocarp.  
  2. Spondiadoideae – Deciduous trees or shrubs that typically cause contact dermatitis. Flower pedicels are often articulated, the gynoecium is 4-5(3) carpelled, and the stigma is only slightly expanded. Fruit is usually more than two-seeded (but sometimes only one), its pericarp may or may not have a lacuna, and the inner mesocarp is made of encircling fibers.

Unplaced includes the Sclerocarya complex of multiple genera, plus Buchanania and Campnosperma that are grouped together, and some completely unplaced ones, including Attilaea, Haplospondias, Koordersiodendron, and Pentaspadon.

Genera:

Anacardioideae: Abrahamia (34), Actinocheita (1), Amphipterygium (5) Anacardium (20), Androtium (1), Astronium (11), Baronia (1), Blepharocarya (2), Bonetiella (1), Bouea (3), Campylopetalum (1), Cardenasiodendron (1), Comocladia (27), Cotinus (7), Dobinea (2), Drimycarpus (4), Euroschinus (9), Faguetia (1), Fegimanra (3), Gluta (35), Haplorhus (1), Heeria (1), Holigarna (9), Laurophyllus (1), Lithraea (3), Loxopterygium (4 inc Apterokarpos), Loxostylis (1), Malosma (1), Mangifera (63), Mauria (15), Melanochyla (23), Metopium (4), Micronychia (10), Mosquitoxylum (1), Myracrodruon (2), Nothopegia (10), Ochoterenaea (1), Orthopterygium (1), Ozoroa (46), Pachycormus (1), Parishia (8), Pegia (2), Pistacia (11), Protorhus (3), Pseudosmodingium (5), Rhodosphaera (1), Rhus (54), Schinopsis (7), Schinus (32), Searsia (110), Semecarpus (87), Smodingium (1), Sorindeia (10), Swintonia (13), Thyrsodium (6), Toxicodendron (27), Trichoscypha (33).

Spondiadoideae: Allospondias (2), Dracontomelon (9), Haematostaphis (1), Pseudospondias (2), Sclerocarya (2), Solenocarpus (2), Spondias (18), Tapirira (9).

Unplaced in a subfamily: Antrocaryon (5), Attilaea (1), Buchanania (26), Campnosperma (14), Choerospondias (1), Cyrtocarpa (5), Harpephyllum (1), Koordersiodendron (1), Lannea (36), Operculicarya (9), Pentaspadon (6), Pleiogynium (3), Poupartia (7), Poupartiopsis (1).

Key Differences From Similar Families

The Anacardiaceae differs from the similar Burseraceae by having usually alternate or sub-opposite leaves or leaflets compared to the almost always opposite leaflets of Burseraceae.

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 Genera Include:

Anacardioideae: Cotinus 1 of 7 NAM & Eurasian sp intro ON; Rhus 5 of 54 Americas, Mediterranean & S+SE Asia spp native all S provinces exc NL; Toxicodendron 3(4) of 27 Americas & S+E Asia spp native all S provinces except NL, inc YT. 

USA Genera Include:

Cotinus 2 of 7 NAM & Eurasian spp inc 1 sp C+E USA endemic and 1 sp intro UT, TX, OK, AR, IL, MO, AL, GA, TN, KY, OH, PA, NY, MD, DE, NJ, CT, MA, VT;Lithraea 1 spp intro CA; Malosma monospecific S NAM endemic native CA; Mangifera 1 of 63 SE & Tropical Asia spp intro FL; Metopium 1 of 4 Mexican & Caribbean endemic spp native FL; Pistacia 3 of 11 pantropical spp inc 1 sp native TX and 2 spp intro CA, UT, OK, AL, GA, VA; Rhus 16 of 54 Americas, Mediterranean & S+SE Asia spp native and intro in the entire US inc HI (exc AK); Schinus 5 of 32 former SAM endemic spp intro CA, TX, AL, FL, and HI; Toxicondrendon 5 of 27 Americas & S+E Asia spp native in all USA.  Spondiadoideae: Spondias 1 of 18 pantropical spp intro FL. 

Mexico Genera Include:

Actinocheita monospecific Mesoamérica endemic of Honduras and Nay, Jal, Col, Mch, Gro, Oax, Pue; Amphipterygium 5 of 5 Mexico & N Neo endemic spp native most of Mexico exc NW Mexico, inc 2 endemics of SW Mexico (1), Dgo + Jal (1); Anacardium ?? of 20 former Neo endemic spp intro Nay, Jal, Col, Mch, Gro, Oax; Astronium 2 of 11 Mexico & Neo endemic spp native NE+SW+SE Mexico, Ver, inc 1 narrow endemic of Ver; Bonetiella monospecific endemic N to C Mexico; Comocladia 5 of 27 Mexico & N Neo endemic spp native in all of Mexico, inc 3 endemic to Mexico, 2 of which are narrow endemics of SW Mexico; Cotinus 3 of 7 NAM & Eurasian spp native Chi, Coa, NL, Tam, Dgo, Zac, Ags, Gto, Qro, Hgo, inc 2 spp endemic to Qro + SLP (1), Dgo + Coa (1); Lithraea 1 of 3 former Neo endemic sp native in Pue; Malosma monospecific S NAM endemic native BCN, BCS, Son, Sin, Chi, Coa, NL, Tam, SLP, Dgo, Zac, Mexican Pacific Islands; Mangifera 1 ?? of 63 SE & Tropical Asia spp intro SW+SE+C Mexico; Metopium 1 of 4 Mexican & Caribbean endemic spp native Ver, Chp, Cam, Tab, Yuc, QR; Mosquitoxylum monospecific N Neo endemic spp native S Mexico in Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Tab, Cam, Yuc, QR; Pachycormus monospecific endemic of BCN, BCS; Pistacia 2 of 11 pantropical spp inc 1 sp native most of Mexico exc BC, BCS, Son, Sin and 1 sp intro N Mexico; Pseudosmodingium 5 of 5 spp endemic to most of Mexico exc SE Mexico; Rhus ?? of 54 Americas, Mediterranean & S+SE Asia spp native throughout Mexico inc Mexican Pacific Is; Schinus ?? of 32 former SAM endemic spp intro N and SW Mexico; Toxicodendron 4 of 27 Americas & S+E Asia spp native all of Mexico. Spondiadoideae: Spondias 3 of 18 pantropical spp native to all Mexico; Tapirira 2 of 7 Mexico & Neo endemic spp native SW Mexico, Pue, Ver, Cam, Tab, Yuc, QR, inc 1 narrow endemic of Oax + Ver. Unplaced: Attilaea monospecific recently published genus endemic to QR, Yuc & Guatemala?; Cyrtocarpa 3 of 5 Mexico & Neo endemic spp native most of Mexico exc Ver, inc 2 endemics of Mexico (1), SW+SE Mexico (1).

Neotropical Genera Include:

Anacardioideae: Actinocheita monospecific Mesoamerica endemic to SC Mexico, Honduras; Amphipterygium 3 of 5 Mexico & Neo endemic spp native Guatemala, Honduras, Nicaragua, NW Costa Rica; Anacardium 20 of 20 former Neo endemic spp native from Honduras S to Peru, Bolivia, Paraguay, S Brazil, Cuba and intro rest of Antilles (exc Netherlands Antilles & Aruba),  Belize, El Salvador, and pantropical; Apterokarpos (~Loxopterygium) endemic to the Caatinga of NE Brazil; Astronium 10 of 11 Mexico & Neo endemic spp native CAM S through tropical SAM to Peru, Bolivia, NE Argentina, S Brazil, inc 5 narrow endemics of Brazil (4), Trinidad-Tobago (1); Cardenasiodendron monospecific endemic to Bolivia; Comocladia 24 of 27 Mexico & N Neo endemic spp native Guatemala, Belize, Greater Antilles, Leeward & Windward Is, 15 spp are single island endemics of Jamaica (6), Hispaniola (5), Cuba (2), Dominican Republic (1), Haiti (1), inc 1 extinct sp of the Windward Is; Haplorhus monospecific endemic to the dry inter-Andean valleys of Peru to N Chile; Lithraea 3 of 3 Mexico & SAM endemic spp of C+E+S Brazil, Bolivia, Paraguay, N Argentina, Uruguay, C Chile and C Mexico, inc 1 narrow endemic of C Chile; Loxopterygium 4 of 4 SAM endemic spp of Venezuela, Guyana, Suriname, French Guiana, Ecuador, Peru, Bolivia, NW Argentina, NE Brazil, inc 1 narrow endemic of NE Brazil; Mangifera 1 of 63 SE & Tropical Asia spp intro Guatemala, Belize, Honduras El Salvador, Costa Rica, Galapagos, Antilles (exc Netherlands Antilles, Aruba), Venezuela, Ecuador, Peru, Paraguay, S Brazil; Mauria 15 of 15 Neo endemic spp native from Costa Rica S to Colombia, Venezuela, Ecuador, Peru, Bolivia, NW Argentina; Metopium 4 of 4 Mexican & Caribbean endemic spp native Guatemala, Belize, Honduras, Bahamas, Turks-Caicos, Antilles (exc Leeward Is & Venezuelan Antilles), SW Caribbean; Mosquitoxylum monospecific N Neo endemic of Jamaica, S Mexico, Guatemala, Belize, Honduras, Nicaragua, Panama, Ecuador; Myracrodruon 2 of 2 SAM endemic spp of Brazil, Bolivia, Paraguay, N Argentina; Ochoterenaea monospecific N SAM endemic, Andean Venezuela and Colombia, Bolivia, Panama?; Orthopterygium monospecific endemic to W Peru; Pistacia 1 of 11 pantropical spp native Guatemala, Honduras, absent SAM; Rhus ?? of 54 Americas, Mediterranean & S+SE Asia spp native Cuba, Bahamas, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, intro Trinidad-Tobago, absent SAM; Schinopsis 7 of 7 SAM endemic spp of Peru, Bolivia, C+E Brazil, Paraguay, N Argentina; Schinus 32 of 32 spp former SAM endemic spp native Peru, Bolivia,  C+E+S Brazil, Paraguay, Uruguay, Chile, Argentina, absent Amazonia, intro Ecuador, Colombia, Bermuda, Bahamas, Turks-Caicos, Cuba, Dominican Republic, Puerto Rico, Trinidad-Tobago, Venezuelan Antilles, Guatemala, El Salvador, Mexico & pantropical; Semecarpus 1 of 87 SE & Tropical Asia spp intro Trinidad-Tobago; Thyrsodium 6 of 6 spp N SAM endemic spp of Colombia, Peru, Bolivia, Venezuela, French Guiana, Guyana, Suriname, N+C+E Brazil, absent Andes; Toxicodendron 3 of 27 Americas & S+E Asia spp inc 2 spp native Bermuda, Bahamas, Guatemala, El Salvador, Honduras, Nicaragua, Panama, Colombia, Venezuela, Ecuador, Peru, Bolivia and 1 Asia sp intro Cuba. Spondiadoideae: Dracontomelon 1 of 9 tropical SE Asia spp intro Trinidad-Tobago; Spondias 12 of 18 pantropical spp inc 11 native Antilles, CAM S through tropical SAM S to Peru, Bolivia, C+SE Brazil, and 1 Asian spp intro Guatemala, Belize, Nicaragua, Panama, Greater Antilles, Colombia, Venezuela, Guyana, French Guyana, N+SE Brazil, Ecuador, Peru, inc 6 narrow endemics of E Brazil; Tapirira 10 of 11 Mexico & Neo endemic spp native CAM and tropical SAM S to Peru, Bolivia, Paraguay, S Brazil, inc 3 narrow endemics of Costa Rica (1), Colombia (1), French Guiana (1). Unplaced: Antrocaryon 1 of 5 otherwise Africa endemic spp is a N SAM endemic native to  Colombia, Amazonian N+C Brazil; Campnosperma 2 of 14 otherwise Madagascar & tropical SE Asia & Australasia spp are Neo endemics from Honduras S to Colombia, Venezuela, Ecuador, Peru and Amazonian N Brazil; Cyrtocarpa 2 of 5 Mexico + Neo endemic spp native Colombia, Venezuela, Guyana, N+C+E Brazil, Netherlands Antilles, inc 1 endemic of Brazil.

Patagonia Genera Include:

Anacardioideae: Lithraea 1 of 3 Mexico + SAM endemic spp native Bio Bio to Los Lagos C Chile; Schinus 6 of 32 former SAM endemic spp native 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 (2023).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this. Annonaceae, Orchidaceae, Poaceae, and Cyperaceae have additional references.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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.
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

18 Sep, 2022

13 Sep, 2022

How to Identify the Acanthaceae Family

Tetramerium nervosum with characteristic bracts frequently found in the Acanthaceae family
Tetramerium nervosum with characteristic bracts frequently found in the Acanthaceae family

Table of contents

Introduction to the Acanthaceae Family

The Acanthaceae family is part of the Lamiales order of core eudicots and, as such, 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. Acanthaceae are usually herbs or shrubs and typically have zygomorphic flowers in white, pink, blue, and shades of purple. Several species are used ornamentally and medicinally. In the field, if you are injured, you can crush the leaves of most Acanthaceae and apply them directly to the wounds to aid in healing. 

Flowers of the Acanthaceae

Plants are always hermaphrodites. Pollination is entomophilous, and the mechanism may be conspicuously specialized or not. Flowers are aggregated in racemes, cymes, or verticils. Often they are in dichasial cymes that become monochasial in the ultimate branches and are often condensed in the leaf axils. Flowers may or may not be pseudanthial. Flowers are both bracteate and bracteolate, and the bracts and bracteoles are often large and showy. Bracts are absent in Thunbergioideae, but bracteoles are present, and bracts are present, but bracteoles are absent in the Nelsonioideae. Flowers are usually more or less zygomorphic or sometimes actinomorphic. The floral irregularity involves the perianth and the androecium. Flowers are 4 or 5 merous and are tetracyclic. Free hypanthium is absent. A hypogynous disk is present. Perianth has a distinct calyx and corolla with 8(6–7) or 10 parts in 2 whorls and may be isomerous or anisomerous. Calyx has 4(3) or 5 parts in 1 whorl, is connate, and is variously entire, lobulate, or blunt-lobed, with the lobes shorter or longer than the tube. Varying degrees of gamosepaly from 0.5–0.9. The calyx may be imbricate, valvate, contorted, or open in bud. When the calyx has 5 parts, it is free with the median member posterior. Corolla has 4 or 5 parts, or 3 parts when the upper lip is suppressed. It is 1 whorled and connate, at least basally. The corolla tube is adaxially deeply split in Acanthus and others, where the upper lip of the corolla is cut away almost to the base of the tube. Corolla lobes may be shorter to longer than the tube. The degree of gamopetaly is 0.5–0.75. The corolla is imbricate ascending cochlear or quincuncial, contorted (left or right), or sometimes with open aestivation (Acanthus). It may be bilabiate, unequal but not bilabiate, with the upper lip at times suppressed, or maybe almost regular.  

Androecium of the Acanthaceae

The androecium has 2 or 4(5) members. Androecial members are adnate with the filaments usually inserted on the corolla tube. They may be all equal or unequal, free of one another or coherent 2 adelphous (partially connate in pairs), and are 1 whorled. Androecium usually includes staminodes or may be made of exclusively fertile stamens (rarely Ruellia).  When present, there are 1-3 staminodes in the same series as the fertile stamens. There are 4(5) or 2 stamens that usually extend beyond the mouth of the flower and are inserted near the base, midway down, or in the throat of the corolla tube, and they are usually didynamous and may or may not be hairy or spurred. Stamens are always oppositisepalous, alternating with the corolla members. Anthers may be separate from one another or connivent, are dorsifixed (often with one lobe reduced or abortive) or adnate, dehiscing via longitudinal slits, are unilocular to bilocular, are tetrasporangiate, and may or may not be appendaged (often with a long connective).

Gynoecium of the Acanthaceae

The gynoecium is 2-carpelled, and the pistil is 2-celled. The gynoecium is synstylovarious to syncarpous and superior. The ovary is 2 locular and sessile. The gynoecium is median. There is one style that is attenuate from the ovary, apical, and usually filiform and much longer than the ovary. There are two stigmas with the posterior often smaller, they are dry type (wet in Thunbergioideae), non-papillate (papillate in Thunbergioideae), and Group II type.  Placentation is axile. Each locule contains 2-50 ovules that are non-arillate or arillate (occasionally with funicular aril), anatropous to campylotropous, and unitegmic.  

Fruit of the Acanthaceae

Fruit is a non-fleshy 2-chambered loculicidal capsule dehiscing somewhat explosively, or sometimes an achene (Avicennia). In most species, the seeds are attached to a small hooked stalk that ejects them from the capsule. Seeds are non-endospermic, borne on retinacula, may or may not be conspicuously hairy, and may or may not contain amyloid.

Habit & Leaf Form of the Acanthaceae

Mostly tropical herbs, shrubs, or twining vines, with some epiphytes or rarely trees (with pneumatophores and sometimes stilt roots in Avicennia). Leaves are usually well developed but sometimes are much reduced, or occasionally plants are aphyllous switch-plants. Leaves may be heterophyllous or isophyllous and are often swollen at the nodes. Branches are terete to angular in cross-section. Herbs are annual or perennial, with or without a basal aggregation of leaves. Most plants are self-supporting but may also be epiphytic or climbing (sometimes in Adhatoda). When they climb, they are stem twiners, root climbers, or scrambling with twiners twining clockwise.  Tree forms are always leptocaul. Plants may be hydrophytic, helophytic (including a few mangroves), mesophytic (many from damp tropical forests), or xerophytic. Leaves are arranged opposite distichous or decussate (rarely alternate or whorled), are simple, and may or may not be gland-dotted. Lamina is dissected or entire, pinnately veined, and cross-venulate. Leaves are exstipulate. Lamina margins are entire, crenate, serrate, or dentate and may be flat, revolute, or involute. Domatia occur in 3 genera as hair tufts. The leaf lamina is dorsiventral (sometimes incomplete) or bifacial (isobilateral in several genera), with or without epidermal salt glands (present on both leaf surfaces in Acanthus ilicifolius). The abaxial epidermis may be papillose or not. Stomata are almost always diacytic, but in Lepidagathis, they are paracytic. Stomata are mainly confined to the abaxial surface or sometimes found on both surfaces. Hairs of diverse kinds are present throughout the family and are usually small and short-stalked and may be eglandular unicellular, uniseriate, or glandular (may always be glandular in Nelsonioideae). Unicellular and multicellular hairs are branched or simple. Lamina does not have secretory cavities. Cystoliths are very often present as streaks in the lamina but are absent in Acantheae and Aphelandreae.In numerous genera, the mesophyll has sclerenchymatous idioblasts as bundles of unique acicular fibers.

Uses of Acanthaceae 

The leaves of many Acanthaceae are used externally for wounds. Research has shown that the family has antifungal, anti-inflammatory, anti-pyretic, antioxidant, insecticidal, immunomodulatory, anti-platelet aggregation, and anti-viral potential. More research is currently underway. Notable ornamentals include bear’s-breech (Acanthus mollis), clockvine (Thunbergia), shrimp plant (Justicia brandegeana), and caricature-plant (Graptophyllum pictum).

Morphology of Acanthaceae in North America

Bracts (typical of Acanthaceae) & Flower of Tetramerium nervosum
Bracts & Flower of Tetramerium nervosum typical of the Acanthaceae family
Growth Habit & Leaves of Ruellia humilis; Acanthaceae family.
Growth Habit & Leaves of Ruellia humilis typical of herbs of the Acanthaceae family
Flower of Ruellia caroliniensis; Acanthaceae family.
Flower of Ruellia caroliniensis, flowers are tubular and may or may not be zygomorphic in Acanthaceae
Flower & Bracts of Elytraria imbricata, common morphology seen in the Acanthaceae family
Flower is zygomorphic typical of Acanthaceae, here the bracts are appressed in Elytraria imbricata
Dehisced capsule (fruit) of Dicliptera resupinata; Acanthaceae family.
Dehisced capsule (fruit) of Dicliptera resupinata; capsules are the most common fruit of Acanthaceae.
Flower of Dicliptera resupinata; Acanthaceae family.
Flower of Dicliptera resupinata; a bilabiate flower enclosed in heart shaped bracts
Floral tubes of Justicia SPP, common in the Acanthaceae family.
Floral tubes of Justicia SPP; Acanthaceae frequently have very long floral tubes.
Flower of Thunbergia grandiflora, a showy member of the Acanthaceae family often used ornamentally
Flower of Thunbergia grandiflora; zygomorphic flowers are typical of Acanthaceae

Acanthaceae Species I have Covered So Far in North America

Acanthoideae Subfamily

Acanthus mollis in cultivation in Gerogia, USA; inflorescences are in tall spikes, basal rosette of leaves; Acanthaceae family.

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 from Paco's Nature Reserve, Sinaloa, Mexico; narrowly triangular flowers, inconspicuous bracts; Acanthaceae family.

Carlowrightia arizonica – Arizona Wrightwort

Heavily branched subshrub 10 – 30 cm tall or sometimes taller. Leaves are simple, opposite, variable in size and shape but ~ lanceolate. Flowers are narrowly triangular with 2 lateral petal lobes, 2 upper lobes fused together with a yellow spot and purple streaks, and a keeled bottom lobe. Native to Texas, Arizona, California, and northern Mexico.

Dicliptera resupinata from Paco's Nature Reserve, Sinaloa; bilabiate flowers surrounded by two heart shape bracts; Acanthaceae family.

Dicliptera resupinata – Arizona Foldwing

Erect herb to 60 cm tall with heavily branching pubescent stems; leaves are lanceolate 2 – 6 cm long. Flowers are bilabiate, light purple with small dark purple lines near the center and surrounded by two heart shape bracts. Native to southeastern AZ, southwest NM, USA, & northwest Mexico.

Justicia pilosella from Carlsbad Caverns Nat'l Park, New Mexico; zygomorphic flowers with a very long floral tube; Acanthaceae family.

Justicia pilosella – Hairy Tubetongue

Herbaceous perennial to 30 cm tall with opposite leaves that may be pubescent or glabrous but with ciliate margins, zygomorphic sessile flowers with a long, white, pubescent tubular corolla with 4 pink or purple lobes, 3 of which bend outwards strongly. Narrow endemic of southern TX and southern NM in the USA, plus arid northeastern Mexico.

Ruellia blechum from Paco's Nature Reserve, Sinaloa, Mexico; conspicuous inflorescence spike with pyramidal bracts; Acanthaceae family.

Ruellia blechum – Green Shrimp Plant

Short herbaceous erect or clambering perennial with opposite ovate leaves and a conspicuously pyramidal shaped inflorescence with often pilose pyramidal bracts from Paco’s Nature Reserve, Sinaloa, Mexico; conspicuous inflorescence spike with pyramidal bracts. Native to Mexico, Central & South America.

Ruellia caroliniensis from Mammoth Cave Park, Kentucky; flowers condensed at top of plant along with the leaves; Acanthaceae family.

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 crowded together at top of 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 from Cole County, MO; trumpet -shaped flowers with a long tube are not condensed at top of the plant; Acanthaceae family.

Ruellia humilis – Wild Petunia

Perennial herb 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 eastern and central USA.

Ruellia nudiflora from Mazatlan, Sinaloa; erect with dichasial inflorescences, lavender flowers with stamens inside the tube; Acanthaceae family.

Ruellia nudiflora – Violet Wild Petunia

Erect 30 – 60 cm tall perennial with few branches and opposite gray-green leaves 5 – 12 cm long with undulate or wavy-toothed margins on short petioles. Terminal dichasial inflorescence of lavender to purple trumpet-shaped flowers with inserted stamens. Flowers last about a day. Native to southern USA (AZ east to AL), Mexico, and Central America.

Ruellia strepens – Smooth Wild Petunia

Herbaceous perennial plant 0.5 – 1 m tall, sometimes branching with hairless or parsley hairy stems; opposite leaves up to 13 cm long, lanceolate to ovate and smooth or slightly undulate margins and mostly hairless surfaces. Nearly sessile flowers in clusters of 1 – 3 in upper axils. Native to southcentral & southeast USA.

Tetramerium nervosum from Paco's Nature Reserve, Sinaloa, Mexico; narrowly triangular flowers, conspicuous bracts; Acanthaceae family.

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 south through Mexico, Central America, south to Venezuela.

Nelsonioideae Subfamily

Elytraria imbricata Playa Brujas, Sinaloa, Mexico; weedy herb, leaves crowded at top, bracts appressed, blue flowers; Acanthaceae family.

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 southern USA south to north Argentina, mostly dry tropical forests.

Thunbergioideae Subfamily

Thunbergia grandiflora in cultivation, Sinaloa, Mexico. Vigorous twining vine with large lavender trumpet-shape flowers; Acanthaceae family.

Thunbergia grandiflora – Blue Trumpet Vine

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.

Taxonomy of Acanthaceae

The Acanthaceae family has between 4000-5600 spp in 207 currently accepted genera. It is part of the Lamiales order of the Core Eudicots. Some genera and species are as of yet unconfirmed, so these numbers may change. There are four subfamilies of Acanthaceae recognized:

  1. Acanthoideae – herbs or sometimes shrubs, with petiole bundles arranged in a circle. Corolla often has the abaxial lobe outside others when in bud. Anthers are sagittate, or the thecae are displaced and not opposite, sometimes with one theca more or less reduced. Stigma is dry and typically bifid. Capsules are obovoid and explosive, seeds are flattened and borne on hook-like hardened funicles. 
  2. Avicennioideae – 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, quincuncial, with nectar glands on the inside of the tube. Stamens are equal and alternate with the corolla. Stigma has two blunt lobes. Fruit is an achene with large seeds that are more or less viviparous. 
  3. Nelsonioideae – herbs with glandular hairs. The inflorescence may be terminal or axillary, bracts are spiral, and bracteoles are sometimes absent. Corolla with descending cochleate aestivation with the adaxial lobes of outside the others. There are 2 stamens with variable anthers with thecae that may or may not be separate. The stigma is broadly lobed. 
  4. Thunbergioideae – twining vines, sometimes erect. Petiole bundles are arcuate or annular with wing bundles. Leaf lamina vernation is strongly curved. Inflorescence is axillary flowers or fasciculate. They have no bracts but have very large bracteoles that may or may not be connate. Anthers have lignified unicellular hairs, are sagittate, dehisce by pores or sometimes slits, and have an elongated connective. The stigma is small, wet, sub-bilobed to trumpet-shaped, and has broad and often unequal papillate lobes.

Genera:

Acanthoideae: Acanthopale (12), Acanthopsis (19), Acanthus (30-39), Achyrocalyx (4), Afrofittonia (1), Ambongia (1), Ancistranthus (1), Andrographis (26), Angkalanthus (1), Anisacanthus (13), Anisosepalum (3), Anisostachya (61 inc Corymbostachys), Anisotes (30 inc Chlamydostachya, Danguya, Himantochilus), Aphanosperma (1), Aphelandra (199 inc Geissomeria), Ascotheca (1), Asystasia (55 inc Styasasia, Asystasiella), Ballochia (3), Barleria (286), Barleriola (4), Blepharis (126), Borneacanthus (6), Boutonia (1), Brachystephanus (21 inc Oreacanthus), Bravaisia (3), Brillantaisia (14), Brunoniella (6), Calacanthus (1), Calycacanthus (1), Camarotea (1), Carlowrightia (27), Celerina (1), Cephalacanthus (1), Cephalophis (1), Chalarothyrsus (1), Chamaeranthemum (5), Champluviera (2), Chileranthemum (3), Chlamydacanthus (3), Chlamydocardia (2), Chorisochora (4), Chroesthes (3), Clinacanthus (4), Clistax (3), Codonacanthus (3), Conocalyx (1), Cosmianthemum (13), Crabbea (13 inc Acanthostelma, Golaea), Crossandra (54), Crossandrella (3), Cuenotia (1), Cyclacanthus (2), Cynarospermum (1), Cyphacanthus (1), Dasytropis (1), Dianthera (41 inc Centrilla, Rhacodiscus), Diceratotheca (1), Dichazothece (1), Dicladanthera (2), Dicliptera (216 inc Dactylostegium, Peristrophe), Dinteracanthus (5), Dischistocalyx (12), Duosperma (26), Dyschoriste (94 inc Sautiera, Apassalus, Chaetacanthus), Ecbolium (22), Echinacanthus (4), Encephalosphaera (3), Eranthemum (22), Eremomastax (1), Filetia (9), Fittonia (2), Forcipella (6), Glossochilus (1), Graphandra (1), Graptophyllum (15), Gymnophragma (1), Gymnostachyum (50), Gypsacanthus (1), Haplanthodes (3), Haplanthus (4), Harpochilus (2), Hemigraphis (38), Henrya (3), Herpetacanthus (21 inc Juruasia, Standleyacanthus), Heteradelphia (2), Holographis (17), Hoverdenia (1), Hulemacanthus (2), Hygrophila (78 inc Hemiadelphis, Nomaphila, Santapaua, Synnema), Hypoestes (138 inc Periestes), Ichthyostoma (1), Isoglossa (70 inc Rhytiglossa), Isotheca (1), Jadunia (2), Justicia (935 inc Adhatoda, Beloperone, Calophanoides, Drejerella, Ixtlania, Jacobinia, Leptostachya, Mananthes, Megalostoma, Neohallia, Odontonemella, Pelecostemon, Pupilla, Sarojusticia, Sarotheca, Sericographis, Siphonoglossa), Kalbreyeriella (4), Kenyacanthus (1), Kosmosiphon (1), Kudoacanthus (1), Lankesteria (7), Lasiocladus (4 inc Synchoriste), Leandriella (2), Lepidagathis (142 – 157 inc Acanthura, Lindauea, Lophostachys, Teliostachya), Leptosiphonium (10), Liberatia (2), Linariantha (1), Louteridium (11), Mackaya (6 inc Odontonemella),  Marcania (1), Megalochlamys (10), Megaskepasma (1 inc Perenideboles), Melittacanthus (1), Mellera (8 inc Ionacanthus), Metarungia (1), Mexacanthus (1), Mimulopsis (18 inc Epiclastopelma), Mirandea (6), Monechma (14 inc Schwabea), Monothecium (3), Morsacanthus (1), Neriacanthus (5), Neuracanthus (32), Nicoteba (4), Odontonema (32 inc Phidiasia), Oplonia (21 inc Forsythiopsis), Orophochilus (1), Pachystachys (18), Pararuellia (11), Pericalypta (1), Petalidium (38), Phaulopsis (21 inc Theileamea), Phialacanthus (5), Phlogacanthus (42 inc Cystacanthus), Physacanthus (3 inc Haselhoffia), Podorungia (5 inc Warpuria), Poikilacanthus (13), Polylychnis (1), Populina (2), Pranceacanthus (1), Pseudacanthopale (1), Pseuderanthemum (128 inc Buceragenia), Pseudodicliptera (4), Psilanthele (1), Psiloesthes (1), Ptyssiglottis (37), Pulchranthus (4), Rhaphidospora (8), Rhinacanthus (25), Rhombochlamys (1), Ritonia (3), Rostellularia (29), Ruellia (361 inc Benoicanthus, Blechum, Dipteracanthus, Eusiphon, Lychniothyrsus, Nothoruellia, Pentstemonacanthus, Pseudoruellia, Spirostigma, Stephanophysum, Tremacanthus, Ulleria), Ruelliopsis (1), Rungia (81), Ruspolia (4), Ruttya (6), Saintpauliopsis (1), Salpinctium (3), Salpixantha (1), Samuelssonia (1), Sanchezia (55 inc Steirosanchezia), Sapphoa (2), Satanocrater (4), Schaueria (15), Schaueriopsis (1), Sclerochiton (18), Sebastiano-schaueria (1), Spathacanthus (4), Sphacanthus (2), Sphinctacanthus (2), Stachyacanthus (1), Stenandrium (66 inc Stenandriopsis), Stenostephanus (81 inc Cylindrosolenium,  Habracanthus, Hansteinia, Kalbreyeracanthus, Lissospermum, Listrobanthes, Nilgirianthus, Razisea), Stenothyrsus (1), Streblacanthus (3 inc Sciaphyllum), Streptosiphon (1), Strobilanthes (448 inc Championella, Clarkeasia, Didyplosandra, Hemigraphis, Hymenochlaena,  Microstrobilus, Pachystrobilus, Paragutzlaffia, Parastrobilanthes, Pleocaulus, Psacadopaepale, Pseudostenosiphonium, Pteracanthus, Pteroptychia, Semnothyrsus, Sericocalyx, Taeniandra, Tarphochlamys, Tetraglochidium, Thelepaepale, Triaenanthus, Xanthostachya, Xenacanthus), Strobilanthopsis (1), Suessenguthia (8), Symplectochilus (2), Tabascina (1), Tessmanniacanthus (1), Tetramerium (30), Thyrsacanthus (6 inc Drejera), Thysanostigma (2), Trichanthera (2), Trichaulax (1), Trichocalyx (2), Trichosanchezia (1), Vindasia (1), Whitfieldia (14), Wuacanthus (1), Xantheranthemum (1), Xerothamnella (2), Xylacanthus (1), Yeatesia (3), Zygoruellia (1). Avicennioideae: Avicennia (8). Nelsonioideae: Aymoreana (?), Elytraria (21), Nelsonia (3), Staurogyne (149 inc Gynocraterium, Ophiorrhiziphyllon, Staurogynopsis).  Thunbergioideae: Anomacanthus (1), Mendoncia (89), Pseudocalyx (6), Thunbergia (151).

Key Differences From Similar Families

Acanthaceae are most often confused with Lamiaceae or Verbenaceae. Both the Lamiaceae and Verbenaceae usually have squarish stems as opposed to terete or angular, and their leaf nodes are not swollen. Acanthaceae has bracteoles not seen in the other two families, and their stamens are often hairy or spurred. Acanthaceae fruits are dry capsules that are often forcibly ejected as opposed to nutlets in Lamiaceae or drupes or berries in Verbenaceae. 

Distribution of Acanthaceae

Acanthanceae are mostly tropical and subtropical species, with a few temperate outliers. Native throughout Africa, Australia, Indonesia, and the Americas. 

Distribution of Acanthaceae in the Americas

Canadian Genera Include:

Acanthoideae: Dianthera 1 of 41 former Americas endemic spp native ON, QC; Justica 1 sp native in QC and ON. 

USA Genera Include:

Acanthoideae: Acanthus 1 of 30 Old World Tropics spp intro CA; Andrographis 1 of 26 Indian & S Asia spp intro VA; Anisacanthus 4 of 13 Americas endemic spp native to AZ, NM, TX; Asystasia 1 of 55 Old World Tropics spp intro FL, AL?; Barleria 2 of 286 pantropical spp intro FL; Carlowrightia 8 of 27 Americas endemic spp native CA, AZ, NM, TX, intro FL; Dianthera 9 of 41 former Americas endemic spp inc 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, VT, genus now intro Africa, Malaya; Dicliptera 4 of 216 pantropical spp native to S half of USA from AZ E to NC and all S plus KS, MO, IL, IN, KY, VA; Dyschoriste 6 of 94 pantropical spp native to NM, AZ, TX, LA, OK, FL, AL, GA, SC; Eranthemum 1 of 22 S Asia spp intro FL; Graptophyllum 1 of 15 African sp intro FL; Hemigraphis 2 of 38 tropical Asia spp intro LA, FL; Henrya 1 of 3 Americas endemic spp native AZ; Hygrophila 6 of 78 pantropical spp native and intro TX, LA, AL, MS, GA, FL, VA, inc 1 sp formerly known as Nomaphila intro TX; Hypoestes 1 of 138 Old World Tropics spp intro HI; Justicia 19 of 935 pantropical 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, VT;  Megaskepasma monospecific former N SAM endemic inro HI; Odontonema 2 of 32 mostly Americas endemic spp intro FL; Pseuderanthemum 1 of 128 pantropical spp intro FL, SC; Ruellia 22 of 361 mostly pantropical 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 inc AZ, NM, but intro in AK, NY; Sanchezia 1 of 55 former Neo endemic spp intro HI; Stenandrium 2 of 66 Americas & African spp native NM, TX, FL, GA; Tetramerium 1 of 30 sub & tropical Americas endemic spp native NM, AZ, TX; Yeatesia 2 of 3 SE NAM endemic spp native TX, LA, AL, MS, FL, GA. Avicennioideae: Avicennia 2 of 8 pantropical spp native TX, MS, AL, GA, LA, FL, intro CA. Nelsonioideae: Elytraria 3 of 21 pantropical spp native NM, AZ, TX, FL, GA, SC, inc 1 narrow endemic of GA, FL, SC; Nelsonia 1 of 3 Old World Tropics spp intro FL. Thunbergioideae: Thunbergia 5 of 151 Old World Tropics spp intro TX, FL and HI. 

Mexico Genera Include:

Acanthoideae: Acanthus 1 of 30 Old World Tropics spp intro Pue; Andrographis ?? of 26 Indian & S Asia spp intro Pue, Tlx, Mor, Ver; Anisacanthus 7 of 13 Americas endemic spp native throughout all of Mexico, inc 3 endemic to Mexico inc 1 a narrow endemic of Son + Chi; Aphanosperma sinaloensis monospecific endemic BC, BCS, Son, Sin, Chi, Dgo, Zac, NL, Tam; Aphelandra ?? of 199 former Mexico & Neo endemic spp native throughout all of Mexico; Barleria ?? of 286 pantropical spp native most of Mexico exc BC, BCS, Son, Sin; Bravaisia 3 of 3 Mexico + N Neo endemic spp native much of Mexico exc BC, BCS, Son, Sin; Carlowrightia 26 of 27 Americas endemic spp native through all of Mexico inc 15 endemics of Mexico, 7 of which are narrow endemics of Tam (3), Chi (2), Sin (1), Yuc (1); Chalarothyrsus monospecific endemic of Nay, Jal, Col, Mch, Gro, Oax, Pue; Chileranthemum 3 of 3 spp native most of Mexico exc BC, BCS, Son, Sin, inc 1 narrow endemic of Jal + Gro; Dianthera ?? of 41 former Americas endemic spp native throughout all of Mexico, genus now intro Africa, Malaya; Dicliptera ?? of 216 pantropical spp native all of Mexico; Dyschoriste ?? of 94 pantropical spp native throughout all of Mexico; Gypsacanthus monospecific endemic of Nay, Jal, Col, Mch, Gro, Oax, Pue; Henrya 3 of 3 Americas endemic spp native in all of Mexico, inc 2 endemic to S+W Mexico; Holographis 17 of 17 spp endemic throughout all of Mexico; Hoverdenia monospecific endemic of Chi, Coa, NL, SLP, Dgo, Zac, Ver; Hygrophila ?? of 78 pantropical spp native Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Yuc, QR, Cam, Tab; Hypoestes 1 of 138 Old World Tropics spp intro much of Mexico exc BC, BCS, Son, Sin, Cam, Tab, Chp, Yuc, QR; Justicia 20+ of 935 pantropical spp native throughout all of Mexico;  Lepidagathis ?? of 142 pantropical spp native Nay, Jal, Col, Gro, Mch, Oax, Chp, Pue, Mor, Ver, Cam, Tab, Yuc, QR; Louteridium 9 of 11 Mexico + Neo endemic spp native most of Mexico exc BC, BCS, Son, Sin, inc 6 narrow endemics of Mch (1), Oax (1), Jal + Mch (1), Ver + Chp (1), Gro (1), Tam (1); Mexacanthus monospecific endemic Nay, Jal, Col, Mch, Gro, Oax; Mirandea 6 of 6 Mexico endemic spp native most of Mexico exc Pue, BC, BCS, Son, Sin; Odontonema ?? of 32 mostly Americas endemic spp native in all of Mexico; Pachystachys 1 of 18 Neo endemic spp native Chp, Cam, Tab, QR, Yuc, intro Nay, Jal, Col, Gro, Mch, Oax; Poikilacanthus 5 of 13 Neo endemic spp native Nay, Jal, Col, Mch, Gro, Oax, Chp, Pue, Tab, Cam, Yuc, QR, inc 4 endemic to Mexico, 3 of which are narrow endemics of Oax (1), Col + Mch + Oax (1); Pseuderanthemum ?? of 128 pantropical spp native throughout all of Mexico; Ruellia ?? of 361 mostly pantropical spp native throughout all of Mexico; Sanchezia ?? of 55 former Neo endemic spp intro Chp, Tab, Cam, Yuc, QR; Spathacanthus 3 of 4 Mexico + CAM endemic spp native Nay, Jal, Col, Mch, Gro, Pue, Ver, Chp, Tab, Cam, Yuc, QR, inc 1 narrow endemic of Ver; Stenostephanus ?? of 81 Mexico & Neo endemic spp native most of Mexico exc BC, Son, Sin; Streblacanthus 2 of 3 Mexico & N Neo endemic spp native Nay, Jal, Col, Mch, Gro, Oax, Ver; Tabascina monospecific endemic Chp, Tab, Cam, Yuc, QR; Tetramerium 25 of 30 sub & tropical Americas spp native in all of Mexico, inc 21 endemics of Mexico, 10 of which are narrow endemics of Oax (3), Mch (2), Gro (2), Oax + Chp (1), Jal + Col (1), Sin (1); Yeatesia 3 of 3 SE NAM endemic spp native Chi, Coa, NL, Tam, Dgo, Zac, SLP, Hgo, Mex?, inc 1 endemic of NE Mexico.  Avicennioideae: Avicennia 2 of 8 pantropical spp native most of Mexico exc C Mexico. Nelsonioideae: Elytraria 4 of 21 pantropical spp native all of Mexico inc Mexican Pacific Is, inc 2 endemics to Mexico; Nelsonia 1 of 3 Old World Tropics spp intro Nay, Jal, Col, Gro, Mch, Oax; Staurogyne ?? of 149 pantropical spp native Nay, Jal, Col, Mch, Gro, Oax; Stenandrium ?? of 66 Americas & African spp native throughout all of Mexico. Thunbergioideae: Mendoncia ?? of 89 Americas and Africa spp native Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Tab, Cam, Yuc, QR; Thunbergia ?? of 151 Old World Tropics spp intro much of Mexico exc BC, BCS, Son, Sin.

Neotropical Genera Include:

Acanthoideae: Ancistranthus monospecific endemic of Cuba; Andrographis ?? of 26 Indian & S Asia spp intro Bahamas, Cuba, Hispaniola, Leeward & Windward Is;Anisacanthus 6 of 13 Americas endemic spp native El Salvador, Honduras, Nicaragua, Costa Rica, E Brazil, inc 5 narrow endemics of Nicaragua (1), Costa Rica (1), E Brazil (3); Aphelandra 199 of 199 former Mexico & Neo endemic spp native Mexico S through CAM, Trinidad-Tobago, tropical SAM S to Peru, N Argentina exc N Chile, Paraguay, Uruguay, intro in Cuba, Dominican Republic, Windward Is, & S Asia; Asystasia 2 of 55 Old World Tropics spp inc 1 sp endemic to Panama (the only New World native sp) and 1 sp intro Belize, El Salvador, Honduras, Nicaragua, Antilles (exc Netherlands Antilles), Venezuela, SE Brazil; Barleria ?? of 286 pantropical spp native CAM, Colombia, Venezuela, Guyana, intro Bahamas, Antilles (exc Cayman Is), SW Caribbean, Trinidad-Tobago, French Guiana, S Brazil; Barleriola 4 of 4 Greater Antilles endemic spp of Cuba, Dominican Republic, Haiti, Puerto Rico; Bravaisia 3 of 3 spp Mexico & N Neo endemic spp native CAM, Cuba, Colombia, Venezuela, Trinidad-Tobago, intro Venezuelan Antilles, Windward Is; Brillantaisia 1 of 14 African spp intro Jamaica; Carlowrightia 4 of 27 Americas endemic spp native CAM (exc Panama), Ecuador, inc 1 narrow endemic of Ecuador;Cephalacanthus monospecific endemic of Peru; Chamaeranthemum 5 of 5 Neo endemic spp of Costa Rica, Peru, SE+S Brazil, inc 4 narrow endemics of Costa RIca (2), Rio de Janeiro SE Brazil (1), Santa Catarina S Brazil (1); Chileranthemum 2 of 3 Mexico + CAM endemic spp native Guatemala, El Salvador; Clistax 3 of 3 spp endemic to N+E+S Brazil;Crossandra 1 of 54 African + Indian spp intro Antilles (exc Cayman Is, Netherlands Antilles), El Salvador, Nicaragua; Cuenotia monospecific endemic NE Brazil; Cyphacanthus monospecific endemic Colombia; Dasytropis monospecific endemic Cuba; Dianthera 41 of 41 former Americas endemic spp native E Canada & USA S through Mexico, CAM, Antilles (exc Cayman Is & Netherland Antilles), and S through tropical SAM S to N Argentina (exc N Chile), intro Bermuda, Africa, Malaya; Dichazothece monospecific endemic SE Brazil; Dicliptera ?? of 216 pantropical spp native CAM, Bahamas, Turks-Caicos, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to N Chile, N Argentina; Dyschoriste ?? of 94 pantropical spp native CAM (exc Belize), Cuba, Hispaniola, Venezuela, Ecuador, Peru, Bolivia, Paraguay, C+S+SE Brazil, N Argentina, Uruguay, intro Leeward Is; Encephalosphaera 3 of 3 N SAM spp endemic spp of Colombia, Ecuador, Peru, N Brazil; Eranthemum 1 of 22 S Asia spp intro El Salvador, Antilles (exc Puerto Rico, Netherlands Antilles, Cayman Is), Trinidad-Tobago, Suriname;Fittonia 2 of 2 former N SAM endemic spp native Colombia, Venezuela, Ecuador, Peru, Bolivia, N Brazil and intro El Salvador, Myanmar, Bangladesh; Graptophyllum 1 of 15 African spp intro Cuba, Hispaniola, Puerto RIco, Jamaica, Leeward Is, Venezuelan Antilles, Trinidad-Tobago, Honduras, Nicaragua, Panama, Venezuela; Harpochilus 2 of 2 spp endemic to NE Brazil; Henrya 1 of 3 Americas endemic spp native CAM (exc Belize); Herpetacanthus 21 of 21 Neo endemic spp native Costa Rica, Honduras, Nicaragua, Panama, Ecuador, French Guiana, Suriname, Peru, Bolivia, N+E Brazil; Hygrophila ?? of 78 pantropical spp native Greater Antilles (exc Cayman Is), Trinidad-Tobago, CAM (exc Costa Rica), tropical SAM S to N Argentina (exc N Chile);Hypoestes 1 of 138 Old World Tropics spp intro Mexico, Guatemala, El Salvador, Honduras, Panama, Colombia, Paraguay;Isotheca monospecific endemic Venezuela and Trinidad-Tobago; Justicia ?? of 935 pantropical spp native widespread CAM, Greater Antilles (exc Cayman Is), Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to N Argentina (exc N Chile); Kalbreyeriella 4 of 4 Neo endemic spp native Costa Rica, Panama, Colombia, N Brazil, Ecuador, Peru; Lepidagathis ?? of 142 pantropical many CAM, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to Peru, NW Argentina, Paraguay, S Brazil; Liberatia 2 of 2 SAM endemic spp of Bolivia, SE+S Brazil; Louteridium 5 of 11 Mexico & Neo spp endemic spp native CAM (exc El Salvador), inc 1 narrow endemic of Belize; Megaskepasma monospecific former N SAM endemic of Suriname, Venezuela, now intro in Costa Rica, Nicaragua, Panama, Trinidad-Tobago and Hawaii; Morsacanthus monospecific endemic S Brazil; Neriacanthus 5 of 5 Neo endemic spp of Panama, Jamaica, Colombia, Ecuador, Peru, Venezuela; Nicoteba 1 of 4 African spp intro Panama, Colombia, Guyana; Odontonema 32 of 32 spp former Americas endemic spp native from Mexico S through CAM, Cuba, Haiti, Leeward & Windward Is, Trinidad-Tobago, Ecuador, Colombia, Venezuela, N+E Brazil, Guyana, intro Paraguay. Dominican Republic, Puerto Rico, Galapagos as well as Tonga and Samoa; Oplonia 16 of 21 Neo & Madagascar spp native Bahamas, Turks-Caicos, Cuba, Hispaniola, Jamaica, Puerto Rico, Leeward Is, Peru, Bolivia, NW Argentina, inc 13 narrow endemics of Cuba (8), Jamaica (3), Peru (2), 5 spp in genus are endemic to Madagascar; Orophochilus monospecific endemic of Peru; Pachystachys 18 of 18 former Neo endemic spp native Panama, Cuba Lesser Antilles (exc Netherlands Antilles), tropical SAM S to N Argentina (exc Suriname, N CHile, Uruguay), intro SW Mexico, Guatemala, El Salvador, Hispaniola, Puerto Rico and S Asia; Phaulopsis 1 of 21 Old World Tropics spp intro Colombia, Jamaica; Poikilacanthus 9 of 13 Neo endemic spp native Guatemala, Honduras, Nicaragua, Panama, Venezuela, Peru, Bolivia, E+S Brazil, Paraguay, Uruguay, N Argentina, inc 6 narrow endemics of Guatemala (2), Bahia NE Brazil (1), São Paulo SE Brazil (1), Peru (1), Trujillo Venezuela (1); Polylychnis monospecific endemic of Guyana & French Guiana; Pranceacanthus monospecific endemic N+C Brazil, Bolivia?; Pseuderanthemum ?? of 128 pantropical spp native CAM, Colombia, Venezuela, Brazil, Ecuador, Peru, Bolivia, intro Cuba, Puerto Rico, Leeward & Windward Is, Venezuelan Antilles, Trinidad-Tobago;Psilanthele monospecific endemic Ecuador; Pulchranthus 4 of 4 SAM endemic spp of Colombia, Venezuela, N Brazil, Suriname, French Guiana, Ecuador, Peru, Bolivia; Rhombochlamys monospecific endemic Colombia; Ruellia ?? of 361 mostly pantropical spp native CAM, Bahamas, Turks-Caicos, Aruba, Antilles (exc Netherlands Antilles), Trinidad-Tobago, SW Caribbean, Galapagos, tropical SAM S to N Argentina (exc N Chile), inc 1 sp formerly known as Ulleria endemic to Suriname; Ruspolia 1 of 4 African spp intro Trinidad-Tobago; Salpixantha monospecific endemic Jamaica; Samuelssonia  monospecific endemic Haiti; Sanchezia 55 of 55 former Neo endemic spp native Panama, Colombia, Venezuela, N Brazil, Ecuador, Peru, Bolivia, now intro Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica, Antilles (exc Cayman Is, Netherlands Antilles), Trinidad-Tobago, plus Mexico, Hawaii, Africa and Asia;Sapphoa 2 of 2 spp endemic to Cuba; Schaueria 15 of 15 spp formerly endemic to C+E+S Brazil, now intro to Trinidad-Tobago; Sebastiano-schaueria monospecific endemic SE Brazil; Spathacanthus 3 of 4 Mexico & CAM endemic spp native Guatemala, Honduras, Costa Rica, inc 1 narrow endemic of Costa Rica; Stachyacanthus monospecific endemic C Brazil; Stenandrium ?? of 66 Americas & African spp native Guatemala, El Salvador, Honduras, Nicaragua, Bahamas, Turks-Caicos, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, tropical SAM S to C Chile, N Argentina (exc Guyana, Suriname, French Guiana, N Chile); Stenostephanus 81 of 81 Mexico & Neo endemic spp native from Mexico S through CAM (exc Belize, El Salvador) to Colombia, Venezuela, N+SE Brazil, Ecuador, Peru, Bolivia; Streblacanthus 3 of 3 Mexico & N Neo endemic spp native Guatemala, Costa Rica, Panama, Peru, N Brazil; Strobilanthes ?? of 448 S + tropical Asia spp intro Belize, El Salvador Honduras, Nicaragua, Panama, Cuba, Hispaniola, Jamaica, Puerto Rico, Windward Is, Venezuelan Antilles, Trinidad-Tobago; Suessenguthia 8 of 8 N SAM endemic spp of N Brazil, Peru, Bolivia;Tessmanniacanthus monospecific endemic Peru; Tetramerium 9 of 30 sub & tropical Americas endemic spp native Guatemala, El Salvador, Honduras, Nicaragua, Panama, Venezuela, Colombia, Ecuador, Peru, Bolivia, inc 5 narrow endemics of Peru; Thyrsacanthus 6 of 6 SAM endemic spp native Venezuela, French Guiana, Guyana, Suriname, Brazil, Bolivia, Paraguay, N Argentina; Trichanthera 2 of 2 Neo endemic spp of Panama, Colombia, Venezuela, N Brazil, Guyana, Suriname, French Guiana, Ecuador, Peru;Trichosanchezia monospecific endemic Peru; Xantheranthemum monospecific endemic Peru. Avicennioideae: Avicennia 3 of 8 pantropical spp native CAM, Bahamas, Aruba, Turks-Caicos, Antilles, SW Caribbean, Trinidad-Tobago, Colombia, Venezuela, Guyana, Suriname, French Guiana, N+E+S Brazil, Uruguay, Ecuador, Peru. Nelsonioideae: Elytraria 11 of 21 pantropical spp native CAM, Cuba, Haiti, Aruba, Trinidad-Tobago, tropical SAM S to Peru, NW Argentina, C+SE Brazil, intro Galapagos, inc 9 narrow endemics of Cuba (6), Haiti (1), Peru (1), Ecuador (1); Nelsonia 1 of 3 Old World Tropics spp intro  El Salvador, Honduras, Nicaragua, Panama, Puerto Rico, Colombia, Ecuador, French Guiana, Bolivia, N+C+E Brazil;Staurogyne ?? of 149 pantropical spp native Nicaragua S to Colombia, Venezuela, Guyana, Suriname, French Suriname, Brazil, Bolivia, Trinidad-Tobago. Thunbergioideae: Mendoncia ?? of 89 Americas & Africa spp native CAM (exc El Salvador), Trinidad-Tobago, tropical SAM S to Peru, Bolivia, Paraguay, S Brazil; Thunbergia ?? several of 151 Old World Tropics spp intro Bahamas, Antilles (exc Cayman Is, Netherlands Antilles), CAM (exc Nicaragua), tropical SAM S to N Argentina (exc French Guiana, N Chile, Uruguay).

Patagonia Genera Include:

Acanthoideae: Stenandrium 1 of 66 Americas & African spp native in Bio Bio C Chile, 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 (2022).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this. Annonaceae, Orchidaceae, Poaceae, and Cyperaceae have additional references.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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.
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

13 Sep, 2022

9 Sep, 2022

How to Identify the Araceae or Arum Family

Arisaema triphyllum flower from Hampton, Virginia. Lyrae Willis photo. Flowers are in a spadix and the spadix is enclosed in a sheath, typical of the Araceae family.
Arisaema triphyllum flower from Hampton, Virginia. Lyrae Willis photo. Flowers are in a spadix and the spadix is enclosed in a sheath, typical of the Araceae family.

Table of contents

Introduction to the Araceae Family

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 it is often found in wet forests and swamps in the region. Most people don’t like the smell, hence the name, however, I love the smell because I love swamps, and when I smell skunk cabbage, odds are there is a swamp nearby for me to explore!  

The Araceae family is part of the Alismatales Order of the Monocot flowering plants. As a monocot, they typically have parallel veins in their leaves. Their flowers are not typical at all for a monocot, however. They often lack a perianth and almost always are densely packed into a cylindrical spadix and enclosed by a characteristic spathe. This is a defining feature of this family, making it very easy to recognize in the field.

Flowers of the Araceae

Plants may be hermaphrodite, monoecious, or rarely dioecious. The inflorescence is characteristic of the family, a terminal cylindrical or ovoid spadix on a peduncle with 3-900 sessile flowers 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 in a pouch. Flowers are small, sessile, actinomorphic, ebracteate, hypogynous, and often possess a strong odor that most find unpleasant. The perianth is usually only present in bisexual flowers, and no hypanthium is present. When present, the perianth is 2-whorled with 4-9 parts that may be free or basally joined.  

Androecium of the Araceae

Androecium has 4, 6, or 8(1-32) members. Stamens may or may not all be fertile, staminodes are sometimes present. Stamens may be free or connate in synandria. The arrangement is antitepalous in hermaphrodite flowers that possess a perianth. Anthers are often subsessile, and dehiscence is poricidal, longitudinal, or transverse. 

Gynoecium of the Araceae

The gynoecium has one ovary that is 1-3(to many) locular, may be sessile or embedded in the spadix, and is syncarpous. The ovary is superior with 3(1-50) carpels, usually with as many locules as carpels. There is usually one short style (sometimes absent) with a hemispheric, capitate, or discoid stigma that is sometimes strongly lobed. Placentation is parietal, axile, basal, or apical. Ovules are one to many per carpel and are usually anatropous and bitegmic.  

Fruit of the Araceae

The fruits 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, almost always possess endosperm, are oily, sometimes starchy, and sometimes possess a fleshy seed coat.

Habit & Leaf Form of the Araceae

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. Plants typically have calcium oxalate crystals or raphides, milky or watery latex, 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 perforate or fenestrate. Leaf shape is elliptic to obovate or spatulate and sometimes sagittate–cordate. Venation can be parallel, pinnate-netted, or palmate-netted. 

Uses of Araceae 

Many Araceae are toxic due to the presence of calcium oxalate crystals which can irritate the digestive tract when ingested. Despite this, however, many are 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 house plants, including Dieffenbachia, Caladium, Philodendron, Zantedeschia, and many more. The Araceae also have unique plants such as Amorphophallus titanum, which has the most massive inflorescence in all the Angiosperms, and Wolffia spp, which have the smallest flowers.   

Morphology of Araceae in North America

Lysichiton americanus of the Orontioideae subfamily with its enclosing spathe that opens vertically, leaves lack stems and grow in a basal rosette. Araceae family
Lysichiton americanus of the Orontioideae subfamily with its enclosing spathe that opens vertically, leaves lack stems and grow in a basal rosette.
Arisaema triphyllum of the Aroideae subfamily with its green spadix enclosed in a spathe with a hooded top. Leaves with long stems from the ground. Araceae family
Arisaema triphyllum of the Aroideae subfamily with its green spadix enclosed in a spathe with a hooded top. Leaves with long stems from the ground.
Anthurium andraeanum of the Pothoideae subfamily is a common houseplant, its spathe does not enclose the flower when it matures. Araceae family
Anthurium andraeanum of the Pothoideae subfamily is a common houseplant, its spathe does not enclose the flower when it matures. Leaves with long stems.
Lemna minor of the Lemnoideae subfamily, a free floating aquatic with thalloid leaves and roots, flower is reduced to a single stamen & ovary in a pouch. Araceae family.
Lemna minor of the Lemnoideae subfamily, a free floating aquatic with thalloid leaves and roots, flower is reduced to a single stamen & ovary in a pouch.
Arum italicum of the Aroideae subfamily in cultivation. Shows the heads of berries that are common with much of the Araceae family.
Arum italicum of the Aroideae subfamily in cultivation. Shows the heads of berries that are common with much of the Araceae family.
Arum italicum of the Aroideae subfamily in cultivation. These have a vertically opening spathe that is much larger than its spadix. Araceae family
Arum italicum of the Aroideae subfamily in cultivation. These have a vertically opening spathe that is much larger than its spadix.

Araceae Species I have Covered So Far

Aroideae Subfamily

Arisaema dracontium the Green Dragon native to E North America inc NE Mexico. It has a very long tip to its spadix. Araceae family

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. Native to eastern North America, including northeastern Mexico.

Arisaema quinatum is sometimes a subspecies of Q. triphyllum and differs by having 5 leaves. This was in Georgia, USA; Araceae family

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 to southeastern USA from Texas east to North Carolina.

Arisaema triphyllum is native through east North America inc northeast Mexico. This was in Virginia. Araceae family

Arisaema triphyllum – Jack-in-the-Pulpit

Herbaceous perennial with trifoliate compound leaves on long petioles from the ground up. Flowres 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 through eastern North America.

Arum italicum in cultivation in Georgia. It has sagittate leaves and a large yellow spathe that surrounds its spadix; Araceae family.

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 sometimes in own Calloideae subfamily, native to north temperate regions. This was in Midland, MI, USA; Araceae family.

Calla palustris – Bog Arum

Aquatic perennial with rounded to cordate leaves 6 – 10 cm long and nearly or as wide on 10 – 20 cm petiole. Flowers in a greenish-yellow spadix and enclosed by a white sheath. Fruit is a cluster of red berries. Native to cool temperate areas of the northern hemisphere. This was in Midland, MI, USA.

Colocasia esculenta or Taro is native to S Asia but introduced in North America & is invasive. This was in Hotsprings, AR, USA; Araceae family.

Colocasia esculenta – Taro

Herbaceous perennial from an edible corm with large sagittate leaves on long thick petioles. Spreads vegetatively and rarely flowers. Native to tropical eastern Asia but introduced in North America, and is invasive. This was in Hotsprings, AR, USA

Peltandra virginica or Green Arrow Arum is native through east North America. This was near Atlanta, GA, USA; Araceae family.

Peltandra virginica – Green Arrow Arum

Mostly aquatic herbaceous perennial with large sagittate leaves, pale green to white inflorescences enclosed in a darker colored spathe. Grows in wet, swampy areas. Native throughout eastern North America.

Lemnoideae Subfamily

Lemna minor Common Duckweed is native all over North America & elsewhere. This was in Sinaloa, Mexico; Araceae family.

Lemna minor – Common Duckweed

A tiny floating aquatic with two (1 – 4) small leaves and a single free-floating root. Spreads vegetatively. Flowers are rare and inconspicuous.

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. Native to northwest North America.

Pothoideae Subfamily

Anthurium andraeanum – Painter’s Pallette

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.

Taxonomy of Araceae

Approximately 3500 – 4800 spp in 139 genera and currently eight accepted subfamilies that are currently undergoing revisions: 

  1. Aroideae – Aroideae possess highly variable growth forms and growth forms making generalizations difficult. They have staminate flowers with connate stamens with a thick connective. Their pistillate flowers have staminodes. Neither flower type has a perianth. Stigmas, placentation, ovules, etc are all variable. Their distribution is cosmopolitan.
  2. Gymnostachydoideae – Leaves are two-ranked, linear, margins are minutely toothed, and there is no distinction between the blade and petiole. Their inflorescences are branched. These are restricted to eastern Australia. 
  3. Lasioideae – These are often prickly, rooted aquatics. Their petioles are long, warty, aculeate, or brightly colored, and their spathe is often spirally twisted.  Their inflorescence flowers basipetally, and they may or may not have a perianth. They have up to 12 stamens, and their anthers have oblique pore-like slits. They are found pantropically. 
  4. Lemnoideae – 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.
  5. Monsteroideae – Herbs, climbers, and epiphytes. Their pollen is inaperturate, the style has abundant trichosclereids, ovules 1-4(-many) per carpel are often basal or sometimes hemianatropous, and there are more than 10 seeds per fruit that are often embedded in mucilage. Distribution is pantropical. 
  6. Orontioideae – A variable group that has no vessels, possesses biforine raphides (exc Lysichiton), leaf blades have a midrib (exc Orontium), have flowers with usually inferior ovaries (exc Orontium), may or may not have styles. Their ovules are either hemianatropous or basal. Distribution is north temperate. 
  7. Pothoideae – The spathe does not enclose the spadix, may be erect to reflexed and is persistent in the fruit. Placentation of ovules is basal or parietal. Distribution is pantropical, excluding Africa. 
  8. Zamioculcadoideae – Rhizomatous plants with leaves that are usually 1-3-compound or simple in Stylochaeton. Leaf fine venation is reticulate, and the leaves are pulvinate along the petiole or petiolules.  They have staminate and pistillate flowers. Placentation of ovules is axile and there is one ascending ovule per carpel. Distribution is restricted to Africa.  

Genera:

Aroideae: Adelonema (16), Aglaodorum (1), Aglaonema (27), Alocasia (104), Ambrosina (1), Amorphophallus (235), Anchomanes (6), Anubias (9), Apoballis (12), Aridarum (26), Ariopsis (3), Arisaema (205), Arisarum (6), Arophyton (7), Arum (59), Asterostigma (8), Bakoa (4), Biarum (21), Bognera (1), Bucephalandra (30), Caladium (20-38), Calla (1-2), Callopsis (1), Carlephyton (4), Cercestis (16), Chlorospatha (69), Colletogyne (1), Colobogynium (1), Colocasia (12-17), Croatiella (1), Cryptocoryne (68), Culcasia (30), Dieffenbachia (57-186), Dracunculus (2), Eminium (9), Englerarum (1), Fenestratarum (2), Filarum (1), Furtadoa (4), Galantharum (1), Gamogyne (1), Gearum (1), Gorgonidium (8), Hapaline (8), Helicodiceros (1), Hestia (1), Heteroaridarum (1), Homalomena (145), Hottarum (1), Idimanthus (1), Incarum (1), Jasarum (1), Lagenandra (15), Leucocasia (1), Lorenzia (1), Mangonia (2), Melioblastis (?), Montrichardia (2), Nephthytis (6), Ooia (10), Peltandra (2-4), Philodendron (489-674), Philonotion (3), Phymatarum (1), Pichinia (1), Pinellia (9), Piptospatha (16), Pistia (1), Protarum (1), Pseudohydrosme (2), Remusatia (4), Rhynchopyle (2), Sauromatum (10), Scaphispatha (2), Schismatoglottis (155), Schottariella (1), Schottarum (2), Spathantheum (1), Spathicarpa (3), Stauromatum (?), Steudnera (11), Synandrospadix (1), Syngonium (38-39), Taccarum (6), Thaumatophyllum (19-21), Theriophonum (5), Typhonium (77-82), Typhonodorum (1), Ulearum (2), Vietnamocasia (?), Xanthosoma (98-196), Zantedeschia (8), Zara (?), Zomicarpa (2), Zomicarpella (2). Gymnostachydoideae: Gymnostachys (1). Lasioideae: Dracontioides (2), Dracontium (29-30).  Lemnoideae: Anaphyllopsis (3), Anaphyllum (2), Cyrtosperma (13), Lasia (3),Lasimorpha (1), Lemna (13-18), Podolasia (1), Pycnospatha (2), Spirodela (4), Urospatha (11), Wolffia (11), Wolffiella (10). Monsteroideae: Alloschemone (2), Amydrium (5),Anadendrum (12), Epipremnum (15), Heteropsis (19-20), Holochlamys (1), Massovia (?), Monstera (49-69), Rhaphidophora (102), Rhodospatha (30-41), Scindapsus (38), Spathiphyllum (52-60), Stenospermation (52-81). Orontioideae: Lysichiton (3), Lysichitum (1), Orontium (1),Symplocarpus (6). Pothoideae: Anthurium (1139),Pedicellarum (1), Potha (?), Pothoidium (1), Pothos (79), Tapanawa (?). Zamioculcadoideae: Gonatopus (5), Stylochaeton Lepr. (20), Stylochaeton Schott (23), Zamioculcas (1).

Key Differences From Similar Families

The Araceae are 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.     

Distribution of Araceae

The Araceae are most diverse in the neotropics of the Americas but are also found in the Old World tropics and temperate regions.

Distribution of Araceae in the Americas

Canadian Genera Include:

Aroideae: Arisaema 2 of 205 cosmopolitan spp native MB, ON, QC, NB, NS, PE; Arum 1 of 59 Eurasian spp intro BC; Peltandra 1 of 2 E NAM endemic spp native ON, QC; Pinellia 1 of 9 Asia spp ephemeral intro ON; Pistia 1 of 1 pantropical spp intro ON. Calloideae (now a tribe of Aroideae): Calla 1 of 1 north temperate spp native all of Canada except NT. Lemnoideae: Lemna 6 of 18 cosmopolitan spp native all of Canada exc NF where it was intro; Spirodela 1 of 4 cosmopolitan spp native BC, AB, SK, MB, ON, QC, NB, NS, PE, Wolffia 4 of 11 cosmopolitan spp inc 3 native BC, AB, SK, MB, ON, QC, NB and 1 intro ON. Orontioideae: Lysichiton 1 of 3 north temperate spp native BC; Symplocarpus 1 of 6 north temperate spp native ON, QC, NB, NS.

USA Genera Include:

Aroideae: Aglaonema 1 of 27 Asian spp intro FL; Alocasia 1 of 104 Australian/Asian spp intro FL, TX, HI; Arisaema 2 of 205 cosmopolitan spp native E USA from ND S to TX and all states E of that; Arum 2 of 59 Eurasian spp intro WA, OR, CA, MO, IL, VI, SC; Caladium 1 of 38 SAM spp intro LA, FL; Calla 1 of 1 north temperate spp native ND, MN, IA, WI, IL, IN, MI, OH, PA, MD, NJ, NY, CT, RI, MA, VT, NH, ME; Colocasia 1 of 12 Asian spp intro TX, LA, MS, AL, GA, FL, SC, NC, PA, and HI; Cryptocoryne 1 of 68 Asian spp intro TX, FL; Dracunculus 1 of 2 spp intro OR, CA, TN; Peltandra 2 of 2 E NAM spp native OR, CA, OK, TX plus E USA from MN S to LA and all states east, inc 1 endemic to SE USA; Philodendron 1 of 564 of tropical Americas spp intro FL and HI; Pinellia 1 of 9 E Asia spp intro CA, OH, WV, MD, NJ, PA, NY, CT; Pistia 1 of 1 pantropical spp native CA, AZ, CO, KA, TX, MO, LA, MS, GA, FL, SC, NC, OH, MD, DE, NY, NJ, CT; Syngonium 1 of 38 neotropical spp intro FL; Xanthosoma 2 of 98 neotropical spp intro TX, FL, and HI; Zantedeschia 2 of 8 S Africa spp intro CA, OR, PA, and HI. Lemnoideae: Lemna 9 of 18 cosmopolitan spp native throughout entire USA inc AK and HI; Spirodela 2 of 4 cosmopolitan spp native entire continental USA and HI; Wolffia 7 of 11 cosmopolitan spp native most of USA exc NV, AZ, NM, CO; Wolffiella 5 of 10 Cosmopolitan spp native WA, CA, TX, OK, MO, AR, LA, IL, IN, OH, KY, TN, MS, AL, GA, FL, SC, NC, VA, PA, NJ, MA. Monsteroideae: Epipremnum 1 of 15 Asian spp intro FL and HI. Orontioideae: Lysichiton 1 of 3 north temperate spp native AK, WA, OR, CA, ID, MT, WY; Orontium 1 of 1 E USA endemic spp native TX, LA, MS, AL, GA, FL, SC, NC, KY, TN, WV, VI, MD, DE, NJ, PA, NY, CT, RI, MA; Symplocarpus 2 of 6 north temperate spp native MN, IA, WI, IL, IN, OH, KY, TN, NC, VI, WV, MI, PA, MD, DE, NJ, NY, CT, RI, MA, VT, NH, ME.

Mexico Genera Include:

Aroideae: Aglaonema 1 of 27 Asian spp intro Nl, Sin, Jal, Son, Ver, Gro, Chi, Tab, Cam; Alocasia 5 of 104 Australian/Asian spp intro Sin E to Coa and all S Mexico; Arisaema 4 of 205 cosmopolitan spp native (and 1 intro) Sin, NL, Nay, Tam, SLP, Jal, Col, Mic, Mex, Pue, Gro, Ver, Oax, Chi; Arum 1 of 59 Eurasian spp intro NL, Jal, Mex; Dieffenbachia 2 of 57 neotropical spp native Sin to S NL and all through S Mexico; Dracontium 1 of 29 neo endemic spp a narrow endemic of SW Chi; Dracunculus 1 of 2 spp intro Chi, Cam; Leucocasia 1 of 1 S Asia spp intro Jal, Pue; Peltandra 1 of 2 E NAM spp intro Tlx; Philodendron 21 of 564 of tropical Americas spp native Sin to S NL and all through S Mexico; Pinellia 1 of 9 E Asia spp intro Mex; Pistia 1 of 1 pantropical spp native throughout Mexico; Syngonium 9 of 38 neotropical spp native BCS, Sin E to NL and all through S Mexico; Thaumatophyllum 3 of 19 N SAM spp intro Sin, Nay, Jal, Col, Ag, SLP, Gto, Cd Mex, Mex, Pue, Mic, Oax, Ver, Chi, Tab, Yuc, QR; Typhonium 1 of 77 Asia spp intro Oax, Pue, Ver, Chi, SLP; Xanthosoma 8 of 98 neotropical spp native most of Mexico exc Chi, BCN, Son; Zantedeschia 1 of 8 S Africa spp intro Mex. Lemnoideae: Lemna 7 of 18 cosmopolitan spp native throughout entire Mexico; Wolffia 2 of 11 cosmopolitan spp native Jal, Nay, Gto, Chi, Mex, Qro, Mor, Cd Mex; Wolffiella 4 of 10 Cosmopolitan spp native NE+C+SE Mexico; Monsteroideae: Monstera 13 of 49 neotropical spp native Sin E to NL and all through S Mexico; Rhodospatha 1 of 30 neotropical spp native Ver, Chi; Spathiphyllum 5 of 52 Neo & W Pacific spp inc 4 native, 1 intro to Nay E to Ver and all of S Mexico, inc 1 endemic to SE Mexico. Pothoideae: Anthurium 31 of 1139 neotropical spp native (and 1 intro) Sin to S NL and throughout S Mexico. Zamioculcadoideae: Zamioculcas 1 of 1 Africa spp intro QR.

Neotropical Genera Include:

Aroideae: Adelonema 16 of 16 spp Neo endemic spp native Costa RIca, Panama, Columbia, Peru, Bolivia, N Brazil, French Guiana, Guyana, Suriname; Aglaonema 1 of 27 Asian spp intro Cuba, Puerto Rico, Trinidad-Tobago, Venezuelan Antilles; Alocasia 5 of 104 Australian/Asian spp intro Cuba, Hispaniola, Jamaica, Puerto Rico, Leeward & Windward Is, Trinidad-Tobago, Venezuelan Antilles, NE BRazil, Venezuela, Paraguay, Galapagos; Amorphophallus 1 of 235 Old World Tropics spp intro Trinidad-Tobago; Arum 1 of 59 Eurasian spp intro NE Argentina; Asterostigma 8 of 8 W SAM endemic spp native NE+C+SE+S Brazil, NE Argentina; Bognera 1 of 1 sp endemic to N Brazil; Caladium 20 of 20 neotropical endemic spp native Honduras S to Peru, NW Argentina, Brazil, and intro Cubo, Hispaniola, Purto Rico, Leeward & Windward Is, Venezuelan Antilles, Trinidad-Tobago and pantropical; Chlorospatha 69 of 69 Neo endemic spp native Costa Rica, Panama, Columbia, Ecuador; Colocasia 2 of 17 Asian spp intro Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, Trinidad-Tobago, Venezuelan Antilles, Galapagos, Honduras, Nicaragua, Costa RIca, Columbia, Venezuela, Guyana, N+NE+S Brazil, Ecuador, Peru, Bolivia, Paraguay; Croatiella 1 of 1 sp endemic to Ecuador; Dieffenbachia 57 of 57 neotropical endemic spp native S Mexico S to Peru, Bolivia, NE Argentina (exc Uruguay) inc all of West Indies; Filarum 1 of 1 sp endemic to Peru; Gearum 1 of 1 sp endemic to N+C Brazil; Gorgonidium 8 of 8 SAM endemic spp native Peru, Bolivia, NW+NE Argentina; Idimanthus 1 of 1 sp endemic to SE Brazil; Incarum 1 of 1 W SAM endemic sp native to Ecuador, Peru, Bolivia; Jasarum 1 of 1 N SAM endemic sp native Venezuela, Guyana; Lorenzia 1 of 1 sp endemic to N Brazil; Mangonia 2 of 2 E SAM endemic spp native S Brazil, Uruguay; Montrichardia 2 of 2 Neo endemic spp native Guatemala, Belize, Honduras, Nicaragua S to Peru, Bolivia, N+SE Brazil, Trinidad-Tobago, Leeward & Windward Is; Peltandra 1 of 2 E NAM spp native Cuba; approx 564 of 564 Americas endemic spp native from Mexico S through to Peru, Bolivia, NE Argentina (exc Uruguay) and inc all of the West Indies; Philonotion 3 of 3 N SAM endemic spp native Colombia, Venezuela, Guyana, French Guiana, Suriname, N Brazil, Peru, Bolivia; Pistia 1 of 1 pantropical spp native throughout CAM, West Indies, and SAM S to Peru, Bolivia, NE Argentina; Scaphispatha 2 of 2 N SAM endemic spp native N+C+NE Brazil, Bolivia; Spathantheum 1 of 1 W SAM endemic spp native Peru, Bolivia, NW Argentina; Spathicarpa 3 of 3 SAM endemic spp native Brazil, Bolivia, Paraguay, NE Argentina, Uruguay; Synandrospadix 1 of 1 sp endemic to Peru, Bolivia, Paraguay, NW Argentina; Syngonium 38 of 38 Mexico + Neo endemic spp native Mexico So to Peru, Bolivia, C+SE Brazil, Greater Antilles, Trinidad-Tobago, Venezuelan Antilles, intro S Brazil, Bahamas, Netherland Antilles, Leeward & Windward Is, and Oceania; Taccarum 6 of 6 SAM endemic spp native Peru, Brazil, Paraguay, Bolivia, NE Argentina; Thaumatophyllum 19 of 19 SAM endemic spp native N SAM S to Peru, Bolivia, NE Argentina (exc Uruguay), intro Belize; Typhonium 1 of 77 Asia & Australia spp intro NE+S Brazil, Cuba, Trinidad-Tobago, Windward Is; Ulearum 2 of 2 SAM endemic spp native N Brazil, Ecuador, Peru; Xanthosoma 98 of 98 Americas endemic 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, intro to Galapagos, Jamaica, Venezuelan Antilles, Cayman Is; Zantedeschia 1 of 8 S Africa spp intro Nicaragua, Costa Rica, Colombia, Ecuador, NE BRazil, Dominican Republic, Puerto Rico, Trinidad-Tobago; Zomicarpa 2 of 2 spp endemic to NE Brazil; Zomicarpella 2 of 2 N SAM endemic spp native Colombia, N Brazil, Peru. Lasioideae: Dracontioides 2 of 2 spp endemic to NE+SE Brazil; Dracontium 29 of 29 Neo endemic spp native S Mexico, Dominican Republic, Peurto Rico, Trinidad-Tobago, Windward Is, Nicaragua S to Peru, Bolivia, Paraguay, C+SE Brazil. Lemnoideae: Anaphyllopsis 3 of 2 N SAM endemic spp native Venezuela, French Guiana, Suriname, N Brazil; Lemna 4 of 18 cosmopolitan spp native throughout the entire Neotropical zone S to C Chile, Argentina; Spirodela 3 of 4 cosmopolitan spp inc 2 native and 1 intro throughout all of Neo zone exc Guyana, French Guiana, Galapagos, N Chile; Urospatha 11 of 11 Neo endemic spp native Guatemala, Honduras, Nicaragua S to Peru, Bolivia, Paraguay, C+SE Brazil; Wolffia 5 of 11 cosmopolitan spp inc 3 native (inc 1 endemic to Colombia) and 2 intro, found in Guatemala, El Salvador, Honduras, Greater & Lesser Antilles (exc Venezuelan Antilles), Colombia, Ecuador, Venezuela, Suriname, Brazil Bolivia, Paraguay, Uruguay, C Chile, NE+NW Argentina; Wolffiella 5 of 10 Cosmopolitan spp native Guatemala, El Salvador, Honduras, Costa Rica S to C Chile, N Argentina (exc N Chile), plus Greater Antilles, Leeward & Windward Is, Trinidad-Tobago. Monsteroideae: Alloschemone 2 of 2 N SAM endemic spp native N Brazil, Bolivia; Epipremnum 1 of 15 S Asia spp intro Bermuda, Cuba, Hispaniola, Puerto Rico, Trinidad-Tobago, Leeward & Windward Is, Venezuelan Antilles, Colombia, Ecuador, Suriname, E Brazil; Heteropsis 19 of 19 Neo endemic spp native Nicaragua S to Peru, Bolivia, N Brazil, plus NE+S+SE Brazil; Monstera 49 of 49 neotropical endemic spp native Mexico S through to Peru, Bolivia, C+S Brazil, Leeward & Windward Is, Netherlands Antilles, intro to Puerto Rico and Asia; Rhodospatha 30 of 30 neotropical spp native S Mexico S to Peru, Bolivia, N+SE Brazil (exc El Salvador), Trinidad-Tobago; Spathiphyllum ?? of 52 Neo, Malesia & W Pacific spp native S Mexico S to Peru, N+C+SE Brazil, Trinidad-Tobago and intro to Cuba, Puerto Rico, Dominican Republic, Venezuelan Antilles; Stenospermation 52 of 52 Neo endemic spp native Guatemala, Honduras, Nicaragua S to Peru, Bolivia, N Brazil, plus SE Brazil. Pothoideae: Anthurium 1139 of 1139 neotropical endemic spp native Mexico all S through to Peru, Bolivia, NE Argentina exc Uruguay plus all throughout the West Indies exc the Bahamas.

Patagonia Genera Include:

Lemnoideae: Lemna 1 of 18 cosmopolitan spp native SE Argentina; Spirodela 1 of 4 cosmopolitan spp native SE Argentina, C Chile; Wolffiella 1 of 10 Cosmopolitan spp native 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 (2022).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this. Orchids, Poaceae, and Cyperaceae have additional references.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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.
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

9 Sep, 2022

7 Sep, 2022

How to Identify the Araliaceae / Ginseng Family

Oplopanax horridus is a shrubby member of the Araliaceae family native to western North America with a disjunct population in the Great Lakes region.
Oplopanax horridus is a shrubby member of the Araliaceae family native to western North America with a disjunct population in the Great Lakes region.

Table of contents

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. Devil’s Club is 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 of core dicots and are very closely related to the Apiaceae family and have many overlapping characteristics. In general, however, the Apiaceae are usually herbs that produce dry schizocarps, while the Araliaceae are usually shrubs or trees and usually produce berry-like drupes. 

Flowers of the Araliaceae

Plants may be hermaphrodite, monoecious, andromonoecious, gynomonoecious, dioecious, or polygamomonoecious. Flowers are aggregated in spikes, heads, and sometimes umbels (compared to usual umbels in the Apiaceae).  Inflorescences are terminal, axillary, leaf-opposed, or rarely epiphyllous. Some genera have racemes, usually with umbels or heads, often massed into compound inflorescences. Flowers are usually more or less 5-merous, cyclic, and rarely calyptrate.  The floral receptacle has neither an androphore nor a gynophore. Perianth has a distinct calyx and corolla or may be petaline, has 10(6–24) parts, and is usually two-whorled and isomerous or anisomerous. In Meryta, it is one whorled where the calyx is entirely lacking. Calyx, when present, has 3–5(–12) parts, is one whorled, free or connate, entire, lobulate, blunt-lobed, or toothed when it is sometimes reduced to small teeth or a mere rim), and is often open when in bud. Corolla has 5(3–13) parts where partially divided or lobed segments sometimes complicate the interpretation of parts. It is one whorled and usually alternates with the calyx, with most genera having five sepals alternating with five petals (exceptions do occur). Corolla is free or partially connate at the base, is rarely calyptrate, may be valvate or imbricate (in Aralieae), is always regular, and is often fleshy.  Petals are usually sessile, often with broad bases inserted around the whole circumference of the upper part of the ovary) or sometimes they are clawed, as in Mackinleyeae.  

Androecium of the Araliaceae

The androecium has 5(3–12) or 10–100 members. Androecial members are free of perianth and one another, all are equal, and all are fertile. Stamens vary in number with 5(3–12) or 10–100, are usually isomerous with the perianth, inflexed in bud, and are filantherous with usually short and fleshy anthers. Stamens may alternate with the corolla members, usually when they equal them in number, or they may be opposite to the corolla members. Anthers are dorsifixed, dehisce via longitudinal slits, and introrse. Anthers are almost always tetrasporangiate (but occasionally appear bisporangiate by fusion during development) or multisporangiate in Octotheca and Dizygotheca.

Gynoecium of the Araliaceae

The gynoecium is 2–5(1–100) carpelled, and the pistil is 2–5(1–100) celled. The gynoecium is synovarious to syncarpous with the styles almost always forming a solid or sometimes hollow stylopodium. Or rarely, the gynoecium can appear monomerous in some Polyscias. It may be partly inferior to inferior or rarely superior (sometimes in Tetraplasandra). Carpel, when monomeric (rarely), is one ovuled with a second abortive ovule. The ovary is 1–100 locular. Locules have no false septa. The epigynous disk is present with a nectariferous disk between the stylopodium and stamens. The number of styles varies widely from 1–100. When there are two to more, then they are free or partially joined and apical. Stigmas are usually present as a frequently double stigmatic crest capping the stylopodium, are wet or dry type, papillate, and Group II and III types.   Placentation when bi/plurilocular (almost always) is axile to apical. When unilocular (rarely) parietal to apical. Ovules in the single cavity 1–2 (if two, then the second is usually abortive) per locule, pendulous, epitropous, with ventral raphe, anatropous, unitegmic, and usually crassinucellate or otherwise tenuinucellate.  

Fruit of the Araliaceae

Fruit may be fleshy or non-fleshy, often an indehiscent berry or drupe with separable pyrenes or with one stone (there are as many pyrenes as locules). Sometimes it will be a schizocarp with 2-5(6-100) mericarps. Gynoecia may combine to form multiple fruits. Seeds are endospermic, ruminate (e.g., Hedera) or not, and oily.

Habit & Leaf Form of the Araliaceae

Perennial trees of moderate size but occasionally very large with Peekeliopanax reaching 40 m high, arborescent, shrubs, woody epiphytes, lianas, or herbs (Panax, Stilbocarpa, some Aralia, etc.). They are non-laticiferous without colored juice, with or without essential oils, and resinous. Occasionally some are switch plants. Plants are green and photosynthesizing. Self-supporting, epiphytic, or climbing; when climbing may be stem twiners or root climbers. Almost always pachycaul with large leaves and thick stems, but sometimes they are leptocaul in Pseudopanax where long and short shoots are seen. Plants may or may not be conspicuously heterophyllous (sometimes e.g., Hedera helix where progression from lobed to entire leaves reflects irreversible shoot maturation). Leaves are usually medium to very large (to over 3 m in Aralia) or rarely small (1–2 cm in Pseudopanax anomalum). Their attachment to the stem is nearly always alternate, mostly spiral, or rarely distichous, four-ranked, opposite (Cheirodendron, Polyscias), or whorled (Panax). Leaves are often leathery, and usually petiolate or sometimes subsessile. They are usually more or less sheathing but may sometimes be non-sheathing, when sheathing, they have free margins. Leaves are gland-dotted or not, aromatic or odorless. Leaf shape is mostly simple (mostly) or compound ternate, pinnate, palmate, multiply compound, and sometimes peltate (some Harmsiopanax). Lamina, when simple, is usually dissected pinnatifid or palmatifid but may be entire. They are pinnately or palmately veined. Leaves may be stipulate or exstipulate. When stipules are present, they are intrapetiolar, often adnate to and scarcely distinguishable from the base of the petiole. Vegetative buds are scaly. Some taxa have spines (as in Oplopanax).

Uses of Araliaceae 

Ornamentals include the angelica tree (Aralia spinosa) and ivy (Hedera spp.) and houseplants such as Hedera, Aralia, Polyscias, Schefflera, Fatsia.  Plus medicinal herbs such as Ginseng roots from Panax quinquefolius and the devil’s club (Oplopanax horridus).  Chinese rice paper from the pith of Tetrapanax papyriferus. Note that Hedera spp have become a widespread invasive species in many areas and should only be used with extreme caution.

Morphology of Araliaceae in North America

Flowers of Aralia nudicaulis of the Araliaceae family
Flowers of Aralia nudicaulis in an umbel. Umbels are not very common, but not uncommon in the Araliaceae family
Leaf of Oplopanax horridus; palmate leaves are quite common in the Araliaecae family.
Leaf of Oplopanax horridus; palmate leaves are quite common in the Araliaecae family.
Inflorescence of Oplopanax horridus; terminal racemes are common in the Araliaceae family
Inflorescence of Oplopanax horridus; terminal racemes are common in the Araliaceae family
Berries of Oplopanax horridus in a raceme; berries are the most common fruit of the Araliaceae family
Berries of Oplopanax horridus in a raceme; berries are the most common fruit of the Araliaceae family
Young Stalk of Aralia spinosa; some members of the Araliaceae have spines on their stems and or leaves
Young Stalk of Aralia spinosa; some members of the Araliaceae have spines on their stems and or leaves
Leaf of Hedera helix showing palmate venation often seen in the Araliaceae family
Leaf of Hedera helix showing palmate venation often seen in the Araliaceae family

Araliaceae Species I have Covered So Far

Aralioideae Subfamily

Aralia nudicaulis – Wild Sarsaparilla

Herbaceous perennial from underground stems. Large compound leaves have 5 (3 – 7) finely serrated leaflets, 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. Native to northern and eastern North America.

Aralia spinosa - Devil's Walking Stick 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.

Aralia spinosa – Devil’s Walking Stick

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.

Evergreen shrub with stout, sparsely branched stems. Large 20 - 40 cm deeply palmately lobed leaves have 7 - 9 lobes, are spirally arranged, leathery and on long petioles. Flowers are small, white, borned in dense terminal compound umbels followed by small black berries. Native to Japan and Korea, cultivated in North America.

Fatsia japonica – Paperplant

Evergreen shrub with stout, sparsely branched stems. Large 20 – 40 cm deeply palmately lobed leaves have 7 – 9 lobes, are spirally arranged, leathery and on long petioles. Flowers are small, white, borned in dense terminal compound umbels followed by small black berries. Native to Japan and Korea, cultivated in North America.

A highly invasive vigorous root-climbing vine with variably 3 - 5 lobed leaves, depending on the cultivar and if 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!

Hedera helix – English Ivy

A highly invasive vigorous root-climbing vine with variably 3 – 5 lobed leaves, depending on the cultivar and if 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!

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. Endemic to North America, mostly the Pacific Northwest, with a small disjunct population in the Great Lakes. Click the link for more info!

Oplopanax horridus – Devil’s Club

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. Endemic to North America, mostly the Pacific Northwest, with a small disjunct population in the Great Lakes. Click the link for more info!

Taxonomy of Araliaceae

1513 spp in 44 genera of the Apiales order of the core Eudicots (dicots). Currently, there are two recognized subfamilies in the Araliaceae. 

  1. Aralioideae – The largest subfamily is made mostly of shrubs and trees, sometimes herbs or root or stem climbers. Leaves are usually pinnately to palmately compound, stipulate with connate, intrapetiolar, hooded, or sometimes cauline stipules. Fruit is almost always a drupe.  
  2. Hydrocotyloideae – Herbaceous perennials, sometimes annuals and some aquatics, the stem has endodermis. Leaf lamina is orbicular–peltate or deeply twice lobed palmately, the margin is crenate or serrate, and they are stipulate cauline or petiolar. 

Genera:

Aralioideae: Anakasia (1), Aralia (73 inc Hunaniopanax, Megalopanax, Pentapanax), Astropanax (15), Astrotricha (20), Brassaiopsis (45), Cephalaralia (1), Cheirodendron (6), Chengiopanax (2), Crepinella (1), Cussonia (20), Dendropanax (91), Didymopanax (16), Eleutherococcus (29), Fatsia (3 inc Boninofatsia), Gamblea (4), Harmsiopanax (3), Hedera (18), Heptapleurum (63), Heteropanax (9), Kalopanax (1), Macropanax (18 inc Cromapanax), Merrilliopanax (3), Meryta (29), Metapanax (2), Motherwellia (1), Neocussonia (16), Neopanax (5), Oplopanax (3), Oreopanax (147), Osmoxylon (61), Panax (13), Plerandra (33), Polyscias (173 inc Arthrophyllum, Cuphocarpus, Gastonia, Munroiodendron, Reynoldsia, Tetraplasandra), Pseudopanax (7), Raukaua (6), Schefflera (309), Sciodaphyllum (21), Seemannaralia (1), Sinopanax (1), Tetrapanax (1), Trevesia (8), Woodburnia (1). Hydrocotyloideae: Hydrocotyle (173 inc Neosciadium), Trachymene (60 inc Uldinia).

Key Differences From Similar Families

The Araliaceae and Apiaceae are both similar to and closely related to each other 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 Apiaceae vs usually present in Araliaceae, and the fruit being a dry schizocarp with two mericarps vs a berry-like drupe in the Araliaceae.

Distribution of Araliaceae

Araliaceae is mostly a tropical family, but some are endemic to temperate climates as well. They are in Eurasia, Africa, Australia, New Zealand, New Caledonia, Pacific islands, and the Americas from Arctic Canada to temperate South America.

Distribution of Araliaceae in the Americas

Canadian Genera Include:

Aralioideae:Aralia 5 of 73 Americas & Asia spp native all of Canada exc NU; Eleutherococcus 1 of 29 E Asian spp intro ON; Hedera 1 of 18 mostly Eurasian spp intro BC, ON, very invasive where it has escaped; Kalopanax monospecific E Asia sp intro ON; Oplopanax 1 of 3 Americas & E Asia spp native BC, AB, YT, ON; Panax 2 of 13 E Asia & NAM spp native ON, QC, NB, NS, PE, most of the genus endemic to Asia. Hydrocotyloideae: Hydrocotyle 4 of 173 cosmopolitan spp native ON, QC, NB, NS, PE, NL (exc Labrador), intro BC.

USA Genera Include:

Aralia 8 of 73 Americas & Asia spp native and intro all of USA exc NV; Cheirodendron 5 of 6 C Pacific endemic spp endemic to HI; Eleutherococcus 1 of 29 E Asian spp intro UT, IN, KY, OH, WV, PA, NY, CT, MA; Hedera 3 of 18 mostly Eurasian spp intro most of USA EXC NV, MT S to NM, ND S to OK, MN, IA, WI, VT, NH, ME and inc HI, very invasive where it has escaped; Heptapleurum ? of 63 S & Tropical Asia spp intro FL and HI; Kalopanax 1 monospecific E Asia sp intro NY, CT, MD, VA, OH, IN; Oplopanax 1 of 3 Americas & E Asia spp native WA, OR, ID, WY, MI, NY, AK; Panax 2 of 13 E Asia spp native all E USA ND S to TX and all E exc ND, TX, FL, most of the genus endemic to E Asia; Polyscias 10 of 173 Old World Tropics & Pacific spp inc 9 spp native/endemic HI (sometimes as Munroiodendron, Reynoldsia, Tetraplasandra) and 1 sp intro FL; Schefflera 2 of 309 pantropical spp (exc Africa) native and intro FL, native HI; Tetrapanax monospecific S China sp intro AL, FL and HI. Hydrocotyloideae: Hydrocotyle 9 of 173 cosmopolitan spp native and intro most USA exc ID, MT, WY, CO, ND, SD, NE, IA and intro HI.     

Mexico Genera Include:

Aralioideae: Aralia ?? of 73 Americas & Asia spp native all of Mexico; Dendropanax ?? of 91 Americas & Tropical & E Asia spp native moist forests at lowland to mid-elevation areas most of Mexico exc BC, BCS, Son, Sin; Didymopanax 1 of 16 Mexico & Neo endemic spp native SW+SE Mexico, Ver; Oreopanax ?? of 147 Mexico & Neo endemic spp native throughout Mexico inc Mexican Pacific Is. Hydrocotyloideae: Hydrocotyle ?? of 173 cosmopolitan spp native throughout all of Mexico.

Neotropical Genera Include:

Aralioideae: Aralia ?? of 73 Americas & Asia spp native CAM, Cuba, Hispaniola, Colombia, Venezuela, Peru, Bolivia, Paraguay, N Argentina, E+S Brazil, most in seasonally dry forests below 500m; Crepinella monospecific SAM endemic sp of Colombia, Venezuela, Guyana, N+C Brazil, Ecuador, Peru; Dendropanax ?? of 91 Americas & Tropical & E Asia spp native moist forests at low to mid-elevation areas up to around 1500m in CAM, Greater Antilles, Leeward Is, Venezuelan Antilles, Trinidad-Tobago, tropical SAM S to Peru, Bolivia, NE Argentina (exc Suriname, French Guiana, Uruguay); Didymopanax 16 of 16 spp Mexico & Neo endemic spp native CAM, Cuba, Hispaniola, Puerto Rico, Leeward Is, Trinidad-Tobago, tropical SAM S to NE Argentina (exc NW Argentina, N Chile), inc 12 narrow endemics of Brazil; Fatsia 1 of 3 Japan, Korea & Taiwan spp intro Juan Fernandez Is; Heptapleurum ?? of 63 S & Tropical Asia spp intro Bermuda, Bahamas, Hispaniola, Jamaica, Puerto Rico, Leeward & Windward Is; Oreopanax 147 of 147 Mexico & Neo endemic spp, mostly in mountains in the tropics above 1500m in CAM, Antilles (exc Cayman Is, Aruba, Netherlands Antilles), Trinidad-Tobago, Colombia, Venezuela, Guyana, Suriname?, French Guiana, N+E+S Brazil, Ecuador, Peru, Bolivia, NW Argentina; Plerandra 1 of 33 S Pacific Is spp intro Trinidad-Tobago; Polyscias ?? of 173 Old World Tropics & Pacific spp intro El Salvador, Bahamas, Hispaniola, Leeward Is, Puerto Rico, Trinidad-Tobago, Venezuelan Antilles; Raukaua 2 of 6 temperate S Hemisphere spp endemic to N+C Chile + S Argentina (1), C Chile (1); Schefflera ?? of 309 pantropical spp (exc Africa) native in moist habitats at mid to high elevations up to 3000 m in Costa Rica, Panama, tropical SAM S to Peru, Bolivia, C+S Brazil, Hispaniola, Jamaica, Leeward & Windward Is, intro Bahamas, Bermuda; Sciodaphyllum 21 of 21 Neo endemic spp of Jamaica, Nicaragua, Costa Rica, Panama, Colombia, Ecuador, Peru, Bolivia, Venezuela; Tetrapanax  monospecific S China sp intro S Brazil. Hydrocotyloideae: Hydrocotyle ?? of 173 cosmopolitan spp widespread in moist habitats of CAM, Bermuda, Bahamas, Cuba, Hispaniola, Jamaica, Puerto Rico, Leeward & Windward Is, Galapagos, and all of SAM, with high diversity in the Andes.

Patagonia Genera Include:

Aralioideae: Raukaua 2 of 6 temperate S Hemisphere spp endemic to N+C Chile + S Argentina (1), C Chile (1). Hydrocotyloideae: Hydrocotyle ? of 173 cosmopolitan spp native Patagonia inc Falkland 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 (2023).  Plant Families of North America.  Not yet published. This is where all of the family descriptions come from. Below should be most of my references for this. Orchids, Poaceae, and Cyperaceae have additional references.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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.
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

7 Sep, 2022

5 Sep, 2022

Plant Families of North America

Table of contents

Welcome to my Plant Families of North America page where you will find descriptions of the plant families in North America I have covered so far. This part is new so please come back as I will continue to add new families as time permits.

All plants are classified by the family they belong to and then by their genus and species name. Their family, in turn, belongs to an Order of similar and closely related families. That Order is then part of the Eudicots, Monocots, Magnoliids, or basal Angiosperms. Below I have organized the families in their Orders so that you can see similarities between related families.

Note that most technical words have a hover-over description available, or go to dictionary of botanical terms to learn more. You will be able to identify plants like a scientist in no time!

Alismatales Order – Monocot Clade

Learn how to identify the Araceae or Arum Family - Plant Families of North America
How to Identify the Araceae or Arum Family

Apiales Order – Eudicot Clade

Learn how to identify the Apiaceae Carrot Family - Plant Families of North America
How to Identify the Apiaceae or Carrot Family
Learn how to identify the Araliaceae Ginseng Family - Plant Families of North America
How to Identify the Araliaceae or Ginseng Family

Caryophyllales Order – Eudicot Clade

How to Identify the Amaranthaceae Family

Gentianales Order – Eudicot Clade

Learn to Identify the Apocynaceae Family

Lamiales Order – Eudicot Clade

Learn how to identify the Acanthaceae Acanthus Family - Plant Families of North America
Learn to Identify the Acanthaceae Family

Magnoliales Order – Magnoliids Clade

Learn how to identify the Annonaceae or Custard Apple Family - Plant Families of North America
How to Identify the Annonaceae or Custard Apple Family

Piperales Order – Magnoliids Clade

Learn how to identify the Aristolochiaceae or Birthwort Family - Plant Families of North America
How to Identify the Birthwort or Aristolochiaceae Family

Sapindales Order – Eudicot Clade

Learn How to Identify the Anacardiaceae Family

Other References

Some other great resources for information on species of North America:

Canadensys Plant Search https://data.canadensys.net/vascan/search

Flora of North America https://eflora.org

iNaturalist Plant Search https://www.inaturalist.org/home

Lady Bird Johnson Wildflower Center https://www.wildflower.org

Native American Ethnobotany http://naeb.brit.org/

USDA Plants Database https://plants.sc.egov.usda.gov/home

Willis, Lyrae (2023).  Plant Families of North America.  Not yet published. 

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

5 Sep, 2022

How to Identify the Annonaceae or Custard Apple Family

Asimina triloba - a temperate species of Annonaceae found as far north as southern Canada. Photo from Hampton, VA, USA by Lyrae Willis
Asimina triloba – a temperate species of Annonaceae found as far north as southern Canada. Photo from Hampton, VA, USA by Lyrae Willis

Table of contents

Introduction to the Annonaceae Family

The Annonaceae is an interesting family of trees and shrubs with unique flowers and fleshy, often edible fruits. The most well-known member of the Annonaceae in North America is the Pawpaw fruit or Asimina triloba. It is the most northern member of this family and produces delicious fruits that taste similar to bananas. The flowers shown in the photo above of Asimina triloba 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.  Sometimes 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.  

Flowers of the Annonaceae

Plants are usually hermaphrodite or sometimes dioecious and rarely monoecious. The flowers are usually trimerous. They are axillary and may be singular or found in racemose compound inflorescences. The receptacle may be elevated, enlarged, or flat. The outer whorls are inserted below the ovaries. Flowers are regular and cyclic or partially acyclic. Sometimes the androecium is spiraled (acyclic). Free hypanthium is absent, and a hypogynous disk is present. The perianth has a distinct calyx and corolla that may be petaline or made of tepals, but it can be hard to determine when the outer 1-2 whorls are sepaloid. Perianth has 9 (10–12) parts, maybe basally joined or free, is usually 3 whorled, isomerous, and may be similar or different in the whorls. Calyx has 3 or 6 parts, typically 2 whorled, free (sometimes basally connate), and the lobes are longer than the tube. Corolla has 3 or 6 parts, is 1–2 whorled, free (sometimes basally connate), and is imbricate or valvate. They may have 6 petals in 2 unequal whorls of 3 with larger outer whorls and fleshier inner whorls that might share the same nectar glands or 6 to 15 petals with impressed veins on the inner face (Annona muricata). 

Androecium of the Annonaceae

The androecium contains 25–100 (usually many) members. Androecial members usually mature centripetally, are free of the perianth and each other, are all equal, usually spiraled, and rarely 3 or 6 whorled. The androecium is usually made entirely of fertile stamens but may include staminodes (e.g. in Uvaria). Staminodes, when present, are external to the fertile stamens and are non-petaloid. Stamens are inserted below the ovary and arranged spirally, forming a ball or flat-topped mass of short, stout filaments and linear to oblong anthers that face upwards.  Anthers are adnate, non-versatile, dehisce via longitudinal slits or longitudinal valves, are extrorse, are tetrasporangiate, and are appendaged via expansion of the connective.

Gynoecium of the Annonaceae

Gynoecium is 10–100(+) carpelled. When syncarpous, the pistil is 1 or 2–15+ celled.  It is usually apocarpous (carpels spiraled or cyclic) or synstylovarious to syncarpous (e.g. Monodora); the ovary is superior. Carpel is 1–10 ovuled. Placentation of free carpels is basal. Ovary when syncarpous is 1 or 2–15+ locular. Stigmas are wet type and papillate, Group III type. Placentation when unilocular is parietal or basal, when plurilocular it is basal. Ovules in the single cavity when unilocular is 1–50 with 10–50 per locule. Ovules are ascending, apotropous, have a ventral raphe, may be arillate or not, are anatropous, bitegmic and crassinucellate.  

Fruit of the Annonaceae

The fruit is a fleshy aggregate that is often made of berries. Fruiting carpels may coalesce into a secondary syncarp or may not. The fruiting carpel is indehiscent and  baccate. Seeds are endospermic with 1 to many per pistil and are often brightly colored. The endosperm is ruminate, oily, and has amyloid.

Habit & Leaf Form of the Annonaceae

Trees, shrubs, or lianas that may be deciduous or evergreen and produce essential oils and may or may not be resinous.  The bark is fibrous and aromatic and pith septate to diaphragmed. Plants may be self-supporting or climbing. When climbing, they are scrambling or stem or petiole twiners. Branching is distichous or spiral.  Leaves are persistent, alternate, non-sheathing, simple, petiolate, and may or may not be gland-dotted or aromatic. Lamina is entire, pinnately veined (sometimes palmately), and is cross-venulate. Leaves are exstipulate. Lamina margins are entire. Domatia occur in 3 genera as pockets or occasionally as hair tufts.

Uses of Annonaceae 

Many have edible fruits, but they should be eaten with caution as they contain varying levels of annonacin which has been implicated in neurodegenerative diseases.   Several important commercial fruits come from Annona spp (atemoya, cherimoya, custard-apple, ilarma, sugar-apple, sweet sop, soursop) and Artabotrys. Medicinal uses include as an analgesic and astringent and to treat various conditions, including snakebite, diarrhea, dysentery, arthritis pain, rheumatism, convulsion, neuralgia, and weight loss.

Morphology of Annonaceae in North America

So far in North America, I have only photographed Asimina triloba, but here are some pictures of different morphological aspects of that species.

Androecium & Gynoecium of Asimina triloba showing a ball that the short, stout filaments of the stamens typically form in Annonaceae species
Androecium & Gynoecium of Asimina triloba showing a ball that the short, stout filaments of the stamens typically form in Annonaceae species
Young Floral Bud of Asimina triloba - shows 2 of the 3 parts of the calyx typical of Annonaceae species (the other sepal is on other side out of view).
Young Floral Bud of Asimina triloba – shows 2 of the 3 parts of the calyx typical of Annonaceae species (the other sepal is on other side, out of view).
Sepals of Asimina triloba - shows the 3 sepals of the calyx that is typical of the Annonaceae family.
Sepals of Asimina triloba – shows the 3 sepals of the calyx that is typical of the Annonaceae family.
Leave of Asimina triloba - simple, petiolate leaves like these are typical of Annonaceae species.
Leave of Asimina triloba – simple, petiolate leaves like these are typical of Annonaceae species.
Bark & Buds of Asimina triloba - fibrous bark is typical of the Annonaceae.
Bark & Buds of Asimina triloba – fibrous bark is typical of the Annonaceae.
Young Tree of Asimina triloba - trees are common among the Annonaceae.
Young Tree of Asimina triloba – trees are common among the Annonaceae.

Annonaceae Species I have Covered So Far in North America

So far in North America, I have only photographed Asimina triloba, the morphology photos above show pictures of that species. When I cover more species, I will add more pictures here.

Asimina triloba of the Annonaceae family

Asimina triloba – American Pawpaw

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, borne singly on stout hairy axillary peduncles, appearing with or before the leaves in spring. Fruit is a large yellowish to brown berry 5 – 15 cm long and 20 – 510g that is edible and sweet. Native to eastern North America. Click here to read my blog on this species

Taxonomy of Annonaceae

The Annonaceae family has approx 2300 species in 111 genera of the Magnoliales Order in the Magnoliids Clade of Peripheral (Non-dicot or monocot) Angiosperms.   

Genera:

Afroguatteria (2), Alphonsea (36), Ambavia (2), Anaxagorea (25), Annickia (11), Annona (171 inc Raimondia, Rollinia, Rolliniopsis), Anonidium (4), Artabotrys (108), Asimina (9), Asteranthe (2), Balonga (1), Bocagea (2), Bocageopsis (4), Boutiquea (1), Brieya (2), Cananga (4), Cardiopetalum (3), Chieniodendron (1), Cleistochlamys (1), Cleistopholis (3), Cremastosperma (31), Cyathocalyx (9), Cymbopetalum (27), Dasymaschalon (27), Deeringothamnus (1), Dendrokingstonia (3), Desmopsis (23), Desmos (18), Diclinanona (3), Dielsiothamnus (1), Disepalum (9), Drepananthus (27), Duckeanthus (1), Duguetia (95 inc Pachypodanthium), Ephedranthus (7), Fenerivia (5), Fissistigma (58), Friesodielsia (38 inc Schefferomitra), Froesiodendron (3), Fusaea (3),  Goniothalamus (134 inc Richella), Greenwayodendron (6), Guatteria (184 inc Guatteriella, Guatteriopsis, Heteropetalum), Hexalobus (5), Hornschuchia (10), Huberantha (34), Isolona (20), Klarobelia (13), Leoheo (1), Letestudoxa (3), Lettowianthus (1), Maasia (6), Malmea (6), Marsypopetalum (5), Meiocarpidium (1), Meiogyne (32 inc Ancana, Fitzalania, Guamia, Oncodostigma, Polyaulax), Mezzettia (4), Miliusa (59), Mischogyne (5), Mitrella (8), Mitrephora (49), Mkilua (1), Monanthotaxis (77 inc Exellia, Gilbertiella), Monocarpia (4), Monocyclanthus (1), Monodora (15), Monoon (72 inc Enicosanthum, Woodiellantha), Mosannona (14), Mwasumbia (1), Neo-uvaria (7), Neostenanthera (5), Onychopetalum (2), Ophrypetalum (1), Orophea (60 inc Mezzettiopsis), Oxandra (28), Phaeanthus (8), Phoenicanthus (2), Piptostigma (13), Platymitra (2), Polyalthia (92 inc Haplostichanthus, Papualthia), Polyalthiopsis (1), Polyceratocarpus (10), Popowia (32), Porcelia (7), Pseudartabotrys (1), Pseudephedranthus (2), Pseudomalmea (4), Pseudoxandra (24), Pseuduvaria (58 inc Craibella, Oreomitra, Petalolophus), Pyramidanthe (1), Ruizodendron (1), Sageraea (9), Sanrafaelia (1), Sapranthus (7), Sirdavidia (1), Sphaerocoryne (7), Stelechocarpus (3), Stenanona (16 inc Reedrollinsia), Tetrameranthus (8), Toussaintia (4), Tridimeris (2), Trigynaea (9), Trivalvaria (8), Unonopsis (48), Uvaria (168 inc Anomianthus, Cyathostemma, Dasoclema, Ellipeia, Ellipeiopsis, Melodorum, Tetrapetalum), Uvariastrum (5), Uvariodendron (15), Uvariopsis (18 inc Dennettia, Tetrastemma), Wangia (2), Wuodendron (1), Xylopia (109 inc Pseudannona, Unona).

Key Differences From Similar Families

The Annonaceae is easily distinguished from other Magnoliales by its fibrous and aromatic bark. Myristicaceae can be differentiated by their red latex. Magnoliaceae can be differentiated by their large deciduous stipules.  

Distribution of Annonaceae

Mostly subtropical and tropical, rarely temperate. Widespread, especially in the Old World. In the Americas, it is found all over the Neotropics and north as far as southern Canada. It is particularly common in lowland forested areas. 

Distribution of Annonaceae in the Americas

Canada Genera:

Asimina 1 of 9 E NAM endemic spp native ON.    

USA Genera:

Annona 3 of 171 Americas + Africa spp native FL; Artabotrys 1 of 108 Old World Tropics spp intro HI; Asimina 9 of 9 E NAM endemic spp native E USA from ND S to TX and all states E exc ND, SD, MN, CT, RI, VT, NH, ME, inc 8 spp endemic to E USA; Deeringothamnus monospecific endemic of FL; Polyalthia 1 of 92 Australasian spp intro FL. 

Mexico Genera:

Anaxagorea 1 of 25 Americas + tropical Asia spp native SW mexico, Ver; Annona (inc Rollinia) 14 of 171 Americas + Africa spp inc 12 native all through Mexico and 1 sp intro Sin E to Tam and S to Oax, Chp, QR, Yuc; Cananga 1 of 2 tropical Asia spp intro SW Mexico, Ver; Cymbopetalum 2 of 27 Mexico + Neo endemic spp native Chp, Ver, Oax?; Desmopsis 8 of 23 Mexico + N Neo endemic spp native Gro, Mic, Chp, Oax, Ver inc 6 narrow endemics of Ver (2), Mic (1), Gro (1), Oax + Ver (2); Guatteria 2 ?? of 184 Neo endemic spp spp native SW+SE+S Mexico, Ver; Mosannona 1 of 14 Mexico + Neo endemic spp native Cam, Chp, QR, Ver, Yuc; Oxandra 4 of 28 Mexico + Neo endemic spp native SW+C+SE Mexico, Ver, inc 1 narrow endemic of Chp; Sapranthus 3 of 7 Mexico + Neo endemic spp native Gro, Oax, QR, Sin, Chp, Ver, inc 1 narrow endemic of Chp; Stenanona 8 of 16 Mexico + N Neo endemic spp native rainforests of SW+SE Mexico, Ver inc 7 narrow endemics of Chp (3), Ver + Oax (2), Tab + Chp (1), Ver + Oax + Chp (1); Tridimeris 2 of 2 Mexican endemic spp native E+C Mexico inc 1 narrow endemic of Chp; Unonopsis ?? of 48 Neo endemic spp native SW+SE Mexico; Uvaria 1 of 168 Old World Tropics spp intro Jal; Xylopia 1 of 169 pantropical spp native S Chi.

Neotropical Genera:

Anaxagorea 22 of 25 Americas + tropical Asia spp native CAM (exc El Salvador), Trinidad-Tobago, tropical SAM S to Peru, Bolivia, C+SE Brazil, inc 5 narrow endemics of Costa Rica & Panama (1), S Venezuela (2), N Peru (1), SE Brazil (1); Annona ?? of 171 spp mostly Americas and some tropical Africa spp native and widely distributed and cultivated for fruit, throughout CAM, Bahamas, Antilles, SW Caribbean, tropical SAM S to N Argentina (exc N Chile); Bocagea 2 of 2 spp endemic to E Brazil; Bocageopsis 4 of 4 SAM endemic spp native Colombia, Venezuela, Guyana, Suriname, French Guiana, N+C+S Brazil, Peru, Bolivia; Cananga 1 of 2 tropical Asia spp intro Guatemala, Nicaragua, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, Trinidad-Tobago; Cardiopetalum 3 of 3 N SAM endemic spp of Suriname, French Guiana, N+C+E Brazil, Peru, Bolivia; Cremastosperma 34 of 34 Neo endemic spp native Costa Rica, Panama, Colombia, Venezuela, N+C Brazil, Ecuador, Peru, Bolivia, found in lowland or pre-montane forests, most diversity in the narrow tropical zone W of the Andes; Cymbopetalum 27 of 27 Mexico + Neo endemic spp native from S Mexico S through CAM and tropical SAM S to Peru, Bolivia, C+E Brazil; Desmopsis 17 of 23 S Mexico + N Neo endemic spp native CAM, Cuba, Colombia; Desmos 1 of 18 Australasian spp intro C+E Brazil, Trinidad-Tobago; Diclinanona 3 of 3 N SAM endemic spp native N+C Brazil, Colombia, Peru, Venezuela; Duckeanthus monospecific narrow endemic of N Brazil; Duguetia 91 of 95 Neo + Africa spp native Nicaragua S through tropical SAM S to Peru, Bolivia, Paraguay, S Brazil, 4 spp endemic to W Africa; Ephedranthus 7 of 7 SAM endemic spp native tropical SAM S to Peru, Bolivia, Paraguay, SE Brazil (exc Ecuador); Froesiodendron 3 of 3 N SAM endemic spp native Colombia, Peru, N Brazil; Fusaea 3 of 3 N SAM endemic spp native N+NE+C Brazil, Colombia, Ecuador, French Guiana, Guyana, Peru, Suriname, Venezuela, Bolivia; Guatteria 184 of 184 Neo endemic spp native from S Mexico S through CAM (exc El Salvador), Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, tropical SAM S to Peru, Bolivia, C+S Brazil, a dominant genus in SAM mature forests; Hornschuchia 10 of 10 narrow endemic spp of E Brazil; Klarobelia 13 of 13 Neo endemic spp native from Costa Rica S to Colombia, Venezuela, N Brazil, Ecuador, Peru, Bolivia, inc several endemics to Ecuador; Malmea 6 of 6 Neo endemic spp native Panama, Colombia, Guyana, Suriname, N+NE Brazil, Peru; Monodora 1 of 15 African spp intro Trinidad-Tobago; Monoon 1 of 72 Australasian spp intro Trinidad-Tobago; Mosannona 14 of 14 Mexico + Neo endemic spp native Guatemala, Belize, Honduras, Costa Rica, Panama, Colombia, N Brazil, Guyana, Suriname, Ecuador, Peru, Bolivia, common in rainforests around Andes, inc 6 narrow endemics of Costa Rica (1), Barro Colorado Is Panama (1), Guatemala (1), Suriname + Guyana (1), Ecuador (1); Onychopetalum 2 of 2 Neo endemic spp of Venezuela, N+C Brazil, Peru, Bolivia; Oxandra 28 of 28 Mexico + Neo endemic spp native S Mexico, Guatemala, Belize, Nicaragua, Costa Rica, Panama, Greater Antilles (exc Cayman Is), Leeward + Windward Is, SW Caribbean, tropical SAM S to Peru, Bolivia, C+SE Brazil, inc 9 narrow endemics of Colombia (3), Suriname (1), Guyana (1), Brazil (4); Polyalthia 1 of 92 SE Asia + Australasia spp intro Trinidad-Tobago; Porcelia 7 of 7 Neo endemic spp native Panama, Colombia, Venezuela, N+E+S Brazil, Ecuador, Peru Bolivia; Pseudephedranthus 2 of 2 N SAM endemic spp of Venezuela, Guyana, Suriname, N Brazil; Pseudomalmea 4 of 4 N SAM endemic spp of Colombia, Venezuela, N Brazil, Ecuador, Peru, Bolivia; Pseudoxandra 24 of 24 SAM endemic spp native Colombia, Venezuela, Guyana, French Guiana, N+C Brazil, Peru, Bolivia; Ruizodendron monospecific N SAM endemic of Colombia, N Brazil, Ecuador, Peru, Bolivia; Sapranthus 6 of 7 Mexico + N Neo endemic spp native CAM, Colombia, inc 1 narrow endemic of Cesar Colombia; Stenanona 9 of 16 Mexico + N Neo endemic spp native rainforests of CAM (exc El Salvador), Colombia, inc 6 narrow endemics of Honduras (2), Costa Rica (1), Panama (1), Colombia (2), the rest are all narrow endemics of Mexico; Tetrameranthus 8 of 8 N SAM endemic spp of N Brazil, Colombia, Venezuela, French Guiana, Ecuador, Peru; Trigynaea 9 of 9 N SAM endemic spp native Colombia, Venezuela, Guyana, Suriname, N+E Brazil, Ecuador, Peru, Bolivia; Unonopsis 48 of 48 Neo endemic spp native S Mexico, CAM (exc El Salvador), tropical SAM S to Peru, Bolivia, C+S Brazil; Uvaria 1 of 168 Old World Tropics spp intro Trinidad-Tobago; Xylopia 40 of 169 pantropical spp native CAM, Cuba, Jamaica, Trinidad-Tobago, tropical SAM S to Peru, Bolivia, NE Argentina. 

Patagonia Genera:

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.
  • Willis, Lyrae (Unpublished).  Plant Families of North America.  Below should be most of my references for this. Orchids, Poaceae, and Cyperaceae have additional references.
  • 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, Alma Rosa Gonzalez-Esquinca (2016). La Familia Annonaceae Juss. En Mexico. Lacandonia ano 10, vol 10, num 2:71-82, Diciembre de 2016.
  • 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.
  • GBIF.org (2020), GBIF Home Page. Available from: https://www.gbif.org
  • Naturalista: CONABIO http://www.naturalista.mx Accessed 2020 – current.
  • 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).
  • Patagonia Wildflowers: Wildflower Identification Site. https://patagoniawildflowers.org/ Accessed throughout the fall of 2020.
  • 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.
  • The Plant List (2013). Version 1.1. Published on the Internet; http://www.theplantlist.org/ (accessed 2020 to 2021). No longer updated. Use WFO below.
  • USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC 27401-4901 USA; accessed throughout fall of 2020.
  • Wikipedia: The free encyclopedia. (2004, July 22). FL: Wikimedia Foundation, Inc. Retrieved throughout 2019-current, from https://www.wikipedia.org
  • WFO (2022): World Flora Online. Published on the Internet; http://www.worldfloraonline.org. Accessed Spring 2022 – current

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5 Sep, 2022