Introduction to the Acanthaceae Family

When you learn how to identify the Acanthaceae family, it helps to understand that it 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. 

Common Botanical Description

If you’re new to plant morphology, this guide is a perfect beginner’s description to learn about the Acanthaceae family, with no need to know any scientific jargon. Below is additional information on uses and morphology, as well as pictures to help identify family members and individual species found in North America. But for researchers or those wanting to learn a more in-depth version, check out the Scientific Botanical Description below the images in addition to genus-level distribution data.

Leaves and Stems of the Acanthaceae: Most members are tropical herbs, shrubs, or climbing vines that twine in a clockwise direction. Leaves are mostly simple (not compound) and arranged in opposite pairs along the stem, which often has swollen joints (nodes). Many species have mineral crystals (cystoliths) visible in their leaves and are covered with small hairs.

Flowers of the Acanthaceae: Flowers may be small or very large and showy and are typically irregular in shape, often forming funnel-shaped flowers or two-lipped flowers where the petals are joined at the base into a tube. Flowers are almost always surrounded by large, showy, leaf-like structures called bracts, which are very characteristic of the family (excluding the Thunbergioideae subfamily, which lacks the showy bracts).

Reproductive Features of the Acanthaceae: Most flowers contain both male and female parts (hermaphrodite or bisexual), with 2-4 stamens (male parts) attached inside the petal tube, often accompanied by smaller, sterile “fake stamens” (staminodes). The superior ovary (attached above the point of petal attachment) has a long, thread-like tube (style) on top to catch pollen and a nectary at the base to attract pollinators.

Fruits of the Acanthaceae: Fruits are almost always a dry, 2-chambered capsule that usually splits explosively when dry to scatter its seeds via small, hooked stalks (retinacula) attached to the seeds that aid in their ejection from the fruit.

Uses of Acanthaceae 

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

Morphology of Acanthaceae in North America

Acanthaceae Species I have Covered So Far in North America

Acanthoideae Subfamily

Acanthus mollis—Bear’s Breeches

A clump-forming perennial herb with tuberous roots, a basal rosette of deeply lobed leaves, and tall spikes of pinkish or purplish flowers. Native to the Mediterranean, often cultivated in North America for its leaves and flowers.

Carlowrightia arizonica – Arizona Wrightwort

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

Dicliptera resupinata—Arizona Foldwing

Erect herb up to 60 cm tall with heavily branching pubescent stems; leaves are lanceolate, 2 – 6 cm long. Flowers are two-lipped, light purple with small dark purple lines near the center, and surrounded by two heart-shaped bracts. Native to southern AZ and NM, United States, and northwest Mexico.

Justicia pilosella—Hairy Tubetongue

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

Ruellia blechum—Green Shrimp Plant

Short herbaceous 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 – Carolina Wild Petunia

Unbranched herbaceous perennial to 1 m with opposite, oval leaves and sessile axillary clusters of 2 – 4 flowers with usually only 1 – 2 open at a time; leaves and flowers are crowded together at the top of the plant. Flowers are light purple to pinkish with a slender corolla tube and 5 petaloid lobes and long-pointed calyx lobes. Native throughout the eastern USA.

Ruellia humilis – Wild Petunia

Perennial herb up to 60 cm tall with tubular, bell-shaped flowers with a long, skinny white tube and five shallow rounded lavender to lilac-colored petals; singly or in clusters in upper axils, not crowded at the top of the plant. Native to the eastern and central USA.

Ruellia nudiflora – Violet Wild Petunia

An erect, 30 – 60 cm tall perennial with few branches and opposite gray-green leaves 5 – 12 cm long with wavy-toothed margins on short petioles. Terminal inflorescence of lavender to purple trumpet-shaped flowers (bractless, hence “nudiflora”) with inserted stamens. Native to the southern USA (AZ east to AL), Mexico, and Central America.

Ruellia strepens – Smooth Wild Petunia

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

Tetramerium nervosum – Hairy Fournwort

Subshrub to 30 cm tall with opposite lanceolate leaves. Flowers in conspicuous pilose leafy bracts on hairy, 4-sided spike inflorescences; tubular with an upper lobe with a violet patch and a yellow base, 2 side lobes, and a keel-like lower lobe. Native to AZ and TX, USA, and south through Mexico and Central America to Venezuela.

Nelsonioideae Subfamily

Elytraria imbricata – Purple Scaly Stem

Weedy subshrub with linear leaves crowded at the top of the plant that may be basal and stemless or up to 60 cm tall. Inflorescences with very appressed bracts, blue flowers. Native from the southern USA to northern Argentina, mostly in dry tropical forests.

Thunbergioideae Subfamily

Thunbergia grandiflora – Blue Trumpet Vine

A twining evergreen vine 2 – 2.5 m long, with large, heart-shaped, bright green leaves and large, showy, lavender-blue, trumpet-shaped flowers up to 7 cm across with a yellow or white throat. Native throughout Southeast Asia. Often cultivated as an annual in North America.

Scientific Description of the Acanthaceae

This section is for researchers or others wanting a more in-depth scientific description to learn how to identify the Acanthaceae family.

Habit & Leaf Form of the Acanthaceae

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 as stem twiners, root climbers, or scramblers 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. The lamina is dissected or entire, pinnately veined, and cross-venulate. Leaves have no stipules. Lamina margins are entire, crenate, serrate, or dentate and may be flat, revolute, or involute. The leaf lamina is dorsiventral (sometimes incomplete) or bifacial (isobilateral in several genera), with or without epidermal salt glands, and the abaxial surface may be papillose. Stomata are almost always diacytic, but in Lepidagathis, they are paracytic; they are mainly confined to the abaxial surface. Diverse hairs are present, including eglandular, unicellular, uniseriate, glandular (may always be glandular in Nelsonioideae), and multicellular branched or simple. Cystoliths are very often present as streaks in the lamina.

Flowers of the Acanthaceae

Plants are always hermaphrodites. Pollination is entomophilous and may be conspicuously specialized. Flowers are aggregated in racemes, cymes, or verticils or often in dichasial cymes that become monochasial but are often condensed in the leaf axils; sometimes they are pseudanthial. Flowers are both bracteate and bracteolate, and they are often large and showy. In Thunbergioideae, bracts are absent, but bracteoles are present. In Nelsonioideae, bracts are present, but bracteoles are absent. Flowers are usually more or less zygomorphic, sometimes actinomorphic. Flowers are 4 or 5 merous and are tetracyclic. Free hypanthium is absent; hypogynous disk is present.

The perianth has a distinct calyx and corolla with 8(6–7) or 10 parts in 2 whorls and may be isomerous or anisomerous. The 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; it may be imbricate, valvate, contorted, or open in bud. When the calyx has 5 parts, the median member is free and located posteriorly. The 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 sometimes adaxially deeply split, where the upper lip of the corolla is cut away almost to the base of the tube, making it two-lipped. The corolla is imbricate, ascending, cochlear, quincuncial, or contorted (left or right), or sometimes with open aestivation.  

Androecium of the Acanthaceae

The androecium has 2 or 4 (5) members that are adnate and usually inserted on the corolla tube. They may be equal or unequal, free of one another, or coherent 2 adelphous (partially connate in pairs), and 1 whorled. The androecium usually includes 1-3 staminodes in the same series as the fertile stamens, or may be made of exclusively fertile stamens (rarely Ruellia). The stamens are usually exserted, and are usually didynamous and may or may not be hairy or spurred. Stamens are always oppositisepalous. 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 terminal style that is attenuate from the ovary and usually filiform and much longer than the ovary. There are two stigmas with the posterior often smaller: they are the dry type (wet in Thunbergioideae), non-papillate (papillate in Thunbergioideae) and the Group II type. Placentation is axile with 2-50 ovules per locule that are non-arillate or arillate (occasionally with a funicular aril), anatropous to campylotropous, and unitegmic.

Fruit of the Acanthaceae

Fruit is a non-fleshy, 2-chambered loculicidal capsule dehiscing somewhat explosively or occasionally an achene (Avicennia). In most species, the seeds are attached to a small hooked stalk that helps eject them from the capsule. Seeds are non-endospermic, borne on retinacula, may be conspicuously hairy, and may contain starch.

Taxonomy of Acanthaceae

The Acanthaceae family has 4605 species in 191 genera. It is part of the Lamiales order of the Core Eudicots. There are four subfamilies of the Acanthaceae that are 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 and 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 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 (20), Acanthostelma (?), Acanthus (30), Achyrocalyx (?), Aechmanthera (?), Afrofittonia (1), Ambongia (1), Ancistranthus (1), Andrographis (27), Angkalanthus (1), Anisacanthus (11), Anisosepalum (3), Anisotes (29), Anthacanthus (?), Aphanosperma (1), Aphelandra (212), Aphelandrella (1?), Ascotheca (1), Asystasia (61), Asystasiella (?), Ballochia (3), Barleria (307), Barleriola (4), Blechum (1), Blepharis (128), Borneacanthus (6), Boutonia (1), Brachystephanus (21), Bravaisia (3), Brillantaisia (14), Brunoniella (6), Buceragenia (2? unplaced), Calacanthus (1), Calycacanthus (2), Camarotea (1), Carlowrightia (27), Celerina (1), Centrilla (?), Cephalacanthus (1), Chaetacanthus (1 unplaced?), Chalarothyrsus (1), Chamaeranthemum (4), Champluviera (2), Chileranthemum (3), Chlamydacanthus (3), Chlamydocardia (2), Chlamydostachya (1?), Chroesthes (4), Clinacanthus (3), Clistax (3), Codonacanthus (3), Cosmianthemum (14), Crabbea (14), Crossandra (54), Crossandrella (3), Cuenotia (1 not in APG), Cyclacanthus (2), Cylindrosolenium (1?), Cyphacanthus (1), Cystacanthus (1 unplaced?), Danguya (?), Dasytropis (1), Dianthera (41 when not inc. in Justicia), Dichazothece (1), Dicladanthera (2), Dicliptera (242), Dinteracanthus (5), Diotacanthus (?), Dischistocalyx (12), Duosperma (26), Dyschoriste (98), Ecbolium (22), Echinacanthus (4), Encephalosphaera (3?), Eranthemum (22), Eremomastax (1), Filetia (9), Fittonia (2), Forcipella (6), Geissomeria (3 unplaced?), Glossochilus (1), Golaea (?), Graphandra (1), Graptophyllum (15), Gymnostachyum (53), Gypsacanthus (1), Habracanthus (?), Haplanthodes (4), Harpochilus (3), Hemigraphis (31), Henrya (3), Herpetacanthus (21), Heteradelphia (2), Holographis (18), Hoverdenia (1), Hulemacanthus (2), Hygrophila (76), Hypoestes (139), Ionacanthus (?), Isoglossa (83), Isotheca (1), Jadunia (2), Juruasia (?), Justicia (959), Kalbreyeriella (4?), Kenyacanthus (1), Kolobochilus (?), Kosmosiphon (1), Kudoacanthus (1), Lankesteria (7), Lasiocladus (4), Leandriella (2), Lepidagathis (157), Leptosiphonium (10), Leptostachya (1), Liberatia (2 not in APG); Linariantha (1), Lindauea (?), Louteridium (11), Mackaya (5), Marcania (1), Megalochlamys (10), Megalostoma (?), Megaskepasma (1), Melittacanthus (1), Mellera (7), Metarungia (1), Mexacanthus (1), Meyenia (1), Mimulopsis (20), Mirandea (6), Monechma (14?), Monothecium (3), Morsacanthus (1), Neohallia (?), Neriacanthus (1), Neuracanthus (32), Odontonema (32), Oplonia (21), Oreacanthus (?), Orophochilus (?), Pachystachys (18), Pararuellia (11), Pelecostemon (?), Perenideboles (?), Pericalypta (1), Peristrophe (?), Petalidium (46), Phaulopsis (21), Phialacanthus (5), Phlogacanthus (42), Physacanthus (3), Podorungia (5), Poikilacanthus (13), Populina (2), Pranceacanthus (1), Pseuderanthemum (134), Pseudodicliptera (4), Psilanthele (1), Ptyssiglottis (38), Pulchranthus (4), Razisea (?), Rhinacanthus (24), Rhombochlamys (1?), Ritonia (3), Ruellia (379), Ruelliopsis (1), Rungia (87), Ruspolia (4), Ruttya (6), Saintpauliopsis (1), Salpixantha (1), Samuelssonia (1), Sanchezia (45), Sapphoa (2), Satanocrater (4), Schaueria (15), Sclerochiton (18), Sebastiano-schaueria (1), Siphonoglossa (?), Spathacanthus (4), Sphacanthus (2), Sphinctacanthus (2), Standleyacanthus (?), Stenandriopsis (20), Stenandrium (50), Stenosiphonium (?), Stenostephanus (95), Stenothyrsus (1), Streblacanthus (3), Streptosiphon (1), Strobilacanthus (?), Strobilanthes (466), Strobilanthopsis (1), Styasasia (?), Suessenguthia (8), Tacoanthus (?), Tessmanniacanthus (?), Tetramerium (31), Thysanostigma (2), Tremacanthus (?), Trichanthera (2), Trichocalyx (2), Trichosanchezia (1),Vindasia (1), Whitfieldia (13), Xantheranthemum (1), Xerothamnella (2), Yeatesia (3), and Zygoruellia (1).

Avicennioideae: Avicennia (8).

Nelsonioideae: Aymoreana (1), Elytraria (22), Nelsonia (3), and Staurogyne (155).

Thunbergioideae: Anomacanthus (1), Mendoncia (90), Pseudocalyx (6), and Thunbergia (150).

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 sp. native to ON and QC (s/t included in Justicia); Justicia 1 sp. native in QC and ON. 

USA Genera Include:

Acanthoideae: Acanthus 1 sp. intro to CA; Andrographis 1 sp. intro to VA; Anisacanthus 4 spp. native to AZ, NM, and TX; Asystasia 1 sp. intro to FL and AL?; Barleria 2 spp. intro to FL; Carlowrightia 8 spp. native to CA, AZ, NM, and TX, and intro in FL; Dianthera 9 spp. including 8 native and 1 intro AZ, KS S to TX, and all E to NJ and S to FL from there plus IA, MI, NY, and VT (s/t included in Justicia); Dicliptera 4 spp. native to S half of USA from AZ E to NC and all S plus KS, MO, IL, IN, KY, and VA; Dyschoriste 6 spp. native to NM, AZ, TX, LA, OK, FL, AL, GA, and SC; Eranthemum 1 sp. intro to FL; Graptophyllum 1 sp. intro to FL; Hemigraphis 2 spp. intro to LA and FL; Henrya 1 sp. native to AZ; Hygrophila 6 spp. native and intro to TX, LA, AL, MS, GA, FL, and VA; Hypoestes 1 sp. intro to HI; Justicia 19 spp. native and intro in most of S half USA CA E to NJ and all S exc NV, UT, CO and inc IA, WI, MI, NY, and VT; Megaskepasma monospecific, formerly N SAM endemic, introduced in HI; Odontonema 2 spp. intro to AL and FL; Pseuderanthemum 1 sp. intro to FL and SC; Ruellia 22 spp. native in most of E half USA from ND S to TX and all E exc. ND, SD, CT, RI, MA, VT, NH, ME and including AZ and NM, but intro in AK and NY; Sanchezia 1 former neoendemic sp. intro to HI; Stenandrium 2 spp. native in NM, TX, FL, and GA; Strobilanthes 1 sp. intro LA and FL; Tetramerium 1 sub & tropical Americas endemic sp. native to NM, AZ, and TX; Yeatesia 2 SE NAM endemic spp. native to TX, LA, AL, MS, FL, and GA. Avicennioideae: Avicennia 2 of 8 pantropical spp native TX, MS, AL, GA, LA, FL, intro CA. Nelsonioideae: Elytraria 3 spp. native to NM, AZ, TX, FL, GA, and SC, including 1 narrow endemic of GA, FL, and SC; Nelsonia 1 sp. intro to FL. Thunbergioideae: Thunbergia 5 spp. intro in TX, FL, and HI. 

Mexico Genera Include:

Acanthoideae: Acanthus 1 sp. intro to Pue; Andrographis 1 sp. intro to Pue, Tlx, Mor, and Ver; Anisacanthus 7 spp. native throughout all of Mexico, including 3 endemic to Mexico; Aphanosperma sinaloensis monospecific endemic to BC, BCS, Son, Sin, Chi, Dgo, Zac, NL, and Tam; Aphelandra 3-7? spp. native throughout all of Mexico; Barleria 1? sp. native to most of Mexico except BC, BCS, Son, and Sin; Bravaisia 3 Mexico + N neoendemic spp. native to much of Mexico exc BC, BCS, Son, and Sin; Buceragenia 2 unplaced narrow endemics of C Mexico; Carlowrightia 26 spp. native through all of Mexico, including 15 endemics of Mexico, 7 of which are narrow endemics of Tam (3), Chi (2), Sin, and Yuc; Chalarothyrsus monospecific endemic of Nay, Jal, Col, Mch, Gro, Oax, and Pue; Chileranthemum 3 spp. native to most of Mexico except BC, BCS, Son, and Sin, and includes 1 narrow endemic of Jal + Gro; Dianthera ?? spp. native throughout all of Mexico, s/t included in Justicia now; Dicliptera ?? many spp. native to all of Mexico; Dyschoriste ~20 spp. native throughout all of Mexico; Gypsacanthus monospecific endemic of Nay, Jal, Col, Mch, Gro, Oax, and Pue; Henrya 3 Americas endemic spp. native in all of Mexico, including 2 endemic to S+W Mexico; Holographis 18 spp. endemic genera found throughout all of Mexico; Hoverdenia monospecific endemic to Chi, Coa, NL, SLP, Dgo, Zac, and Ver; Hygrophila 3? spp. native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Yuc, QR, Cam, and Tab; Hypoestes 1 sp. intro to much of Mexico exc BC, BCS, Son, Sin, Cam, Tab, Chp, Yuc, and QR; Justicia 20+ spp. native throughout all of Mexico; Lepidagathis 1-2 spp. native to Nay, Jal, Col, Gro, Mch, Oax, Chp, Pue, Mor, Ver, Cam, Tab, Yuc, and QR; Louteridium 9 Mexico + neoendemic spp. native to most of Mexico except BC, BCS, Son, and Sin, including 6 narrow endemics of Mch, Oax, Jal + Mch, Ver + Chp, Gro, and Tam; Mexacanthus monospecific endemic of Nay, Jal, Col, Mch, Gro, and Oax; Mirandea 6 Mexico endemic spp. native to most of Mexico except Pue, BC, BCS, Son, and Sin; Odontonema 4-7 spp. native in all of Mexico; Pachystachys 1 neoendemic sp. native to Chp, Cam, Tab, QR, and Yuc, and intro to Nay, Jal, Col, Gro, Mch, and Oax; Poikilacanthus 5 Mexico + neoendemic spp. native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Pue, Tab, Cam, Yuc, and QR, including 4 endemic to Mexico; Pseuderanthemum 5-8 spp. native throughout all of Mexico; Ruellia ~10?? spp. native throughout all of Mexico; Sanchezia 1 former neoendemic sp. intro to Chp, Tab, Cam, Yuc, and QR; Spathacanthus 3 Mexico + CAM endemic spp. native to Nay, Jal, Col, Mch, Gro, Pue, Ver, Chp, Tab, Cam, Yuc, and QR, including 1 narrow endemic of Ver; Stenandrium 8-10 spp. native throughout all of Mexico; Stenostephanus 15 Mexico + neoendemic spp. native to most of Mexico except BC, Son, and Sin; Streblacanthus 2 Mexico & N neoendemic spp. native to Nay, Jal, Col, Mch, Gro, Oax, and Ver; Tetramerium ~25 sub & tropical Americas spp. native in all of Mexico, including 21 endemics of Mexico; Yeatesia 3 SE NAM endemic spp. native to Chi, Coa, NL, Tam, Dgo, Zac, SLP, Hgo, and Mex?, including 1 endemic of NE Mexico. Avicennioideae: Avicennia 2 spp. native to most of Mexico except C. Mexico. Nelsonioideae: Elytraria 4 spp. native to all of Mexico, inc. Mexican Pacific Is., including 2 endemics to Mexico; Nelsonia 1 sp. intro to Nay, Jal, Col, Gro, Mch, and Oax; Staurogyne 1-2? spp. native to Nay, Jal, Col, Mch, Gro, and Oax; Thunbergioideae: Mendoncia 1-2 spp. native to Nay, Jal, Col, Mch, Gro, Oax, Chp, Ver, Tab, Cam, Yuc, and QR; Thunbergia 3? spp. intro to much of Mexico except BC, BCS, Son, and Sin.

Neotropical Genera Include:

Acanthoideae: Acanthus 1 sp. intro to Costa Rica; Ancistranthus monospecific endemic to Cuba; Andrographis 1 sp. intro to Bahamas, Cuba, Hispaniola, Leeward & Windward Is.; Anisacanthus ~9 spp. native to El Salvador, Honduras, Nicaragua, Costa Rica, E Brazil, inc 5 narrow endemics of Nicaragua, Costa Rica, and E Brazil (3); Aphelandra 212 former Mexico & neoendemic spp. native from Mexico S through CAM, Trinidad-Tobago, tropical SAM S to Peru, N Argentina exc. N Chile, Paraguay, and Uruguay, and intro in Cuba, Dominican Republic, and Windward Is.; Asystasia 2 spp intro 2 Cuba, Belize, El Salvador, Honduras, Nicaragua, Antilles (exc. Netherlands Antilles), Venezuela, and SE Brazil; Barleria 1? sp. native to CAM, Colombia, Venezuela, Guyana, intro Bahamas, Antilles (exc. Cayman Is.), SW Caribbean, Trinidad-Tobago, French Guiana, and S Brazil; Barleriola 4 Greater Antilles endemic spp. of Cuba, Dominican Republic, Haiti, and Puerto Rico; Blechum 1 sp? endemic to SE Brazil; Bravaisia 3 Mexico & N neoendemic spp. native to CAM, Cuba, Colombia, Venezuela, and Trinidad-Tobago and intro to Venezuelan Antilles and Windward Is.; Brillantaisia 1 sp. intro Jamaica; Carlowrightia 4 spp. native to CAM (except Panama), and includes 1 narrow endemic in Ecuador; Cephalacanthus monospecific endemic of Peru; Chamaeranthemum 4 neoendemic spp. of Costa Rica, Peru, and SE+S Brazil, including 3 narrow endemics of Costa RIca (2) and Rio de Janeiro SE Brazil; Chileranthemum 2 Mexico + CAM endemic spp. native to Guatemala and El Salvador; Clistax 3 spp. endemic to N+E+S Brazil; Crossandra 1 sp. intro to the Antilles (except Cayman Is. and Netherlands Antilles), El Salvador, and Nicaragua; Cuenotia monospecific endemic NE Brazil; Cyphacanthus monospecific endemic of Colombia; Dasytropis monospecific endemic to Cuba; Dianthera 41 spp. now s/t included in Justicia native from 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), and intro Bermuda; Dichazothece monospecific endemic SE Brazil; Dicliptera at least 20? spp. native to CAM, Bahamas, Turks-Caicos, Greater Antilles (except Cayman Is.), Leeward & Windward Is., Trinidad-Tobago, and tropical SAM S to N Chile and N Argentina; Dyschoriste ~45 spp. native to CAM (except Belize), Cuba, Hispaniola, Venezuela, Ecuador, Peru, Bolivia, Paraguay, C+S+SE Brazil, N Argentina, and Uruguay, and intro Leeward Is.; Encephalosphaera 3 N SAM endemic spp. of Colombia, Ecuador, Peru, and N Brazil (s/t included in Aphelandra); Eranthemum 1 sp. intro to El Salvador, Antilles (excluding Puerto Rico, Netherlands Antilles, and Cayman Is.), Trinidad-Tobago, and Suriname; Fittonia 2 former N SAM endemic spp. native to Colombia, Venezuela, Ecuador, Peru, Bolivia, and N Brazil and intro to El Salvador and Trinidad-Tobago; Graptophyllum 1 sp. intro to Cuba, Hispaniola, Puerto RIco, Jamaica, Leeward Is, Venezuelan Antilles, Trinidad-Tobago, Honduras, Nicaragua, Panama, and Venezuela; Harpochilus 2 narrow endemic spp. of NE Brazil; Henrya 1 sp. native to CAM (excluding Belize); Herpetacanthus 21 neoendemic spp. of Costa Rica, Honduras, Nicaragua, Panama, Ecuador, French Guiana, Suriname, Peru, Bolivia, and N+E Brazil; Hygrophila 3-10? spp. native to Greater Antilles (exc. Cayman Is.), Trinidad-Tobago, CAM (exc. Costa Rica), and tropical SAM S to N Argentina (exc. N Chile); Hypoestes 1 sp. intro in Guatemala, El Salvador, Honduras, Panama, Colombia, and Paraguay; Isotheca monospecific endemic to Venezuela and Trinidad-Tobago; Justicia ~500 spp. native and widespread in CAM, Greater Antilles (exc. Cayman Is.), Leeward & Windward Is., Trinidad-Tobago, and tropical SAM S to N Argentina (exc. N Chile); Kalbreyeriella 4 neoendemic spp. native to Costa Rica, Panama, Colombia, N Brazil, Ecuador, and Peru; Lankesteria 1 sp. intro to Trinidad-Tobago; Lepidagathis ~50-60 spp. native to CAM, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is, Trinidad-Tobago, tropical SAM S to Peru, NW Argentina, Paraguay, and S Brazil; Liberatia 2 SAM endemic spp. of SE+S Brazil (not in APG); Louteridium 5 Mexico & neoendemic spp. native to CAM (exc. El Salvador), including 1 narrow endemic of Belize; Megaskepasma monospecific, a former N SAM endemic of Suriname and Venezuela, now introduced in Costa Rica, Nicaragua, Panama, Trinidad-Tobago, and Comoros; Morsacanthus monospecific endemic of S Brazil; Neriacanthus monospecific endemic sp. of Jamaica; Odontonema 32 former Americas endemic spp native from Mexico S through CAM, Cuba, Haiti, Leeward & Windward Is., Trinidad-Tobago, Ecuador, Colombia, Venezuela, N+E Brazil, and Guyana, and intro Paraguay, the Dominican Republic, Puerto Rico, and Galapagos; Oplonia 16 neoendemic spp (rest of genus is Madagascar) native to the Bahamas, Turks and Caicos, Cuba, Hispaniola, Jamaica, Puerto Rico, Leeward Islands, Peru, Bolivia, and NW Argentina, including 13 narrow endemics of Cuba (8), Jamaica (3), Peru (2); Orophochilus monospecific endemic of Peru; Pachystachys 18 former neoendemic spp. native from S Mexico, Costa Rica, Panama, Cuba, Lesser Antilles (exc. Netherlands Antilles), and tropical SAM S to N Argentina (exc. Suriname, N Chile, and Uruguay), and intro Guatemala, El Salvador, Hispaniola, and Puerto Rico; Phaulopsis 1 sp. intro to Colombia and Jamaica; Phlogacanthus 1 sp intro to Windward Is.; Poikilacanthus 9 Mexico + neoendemic spp. native to Guatemala, Honduras, Nicaragua, Panama, Venezuela, Peru, Bolivia, E+S Brazil, Paraguay, Uruguay, and N Argentina, inc 6 narrow endemics of Guatemala (2), Bahia NE Brazil (1), São Paulo SE Brazil (1), Peru (1), Trujillo Venezuela (1); Pranceacanthus monospecific endemic of N+C Brazil and Bolivia; Pseuderanthemum ~60 spp. native to CAM, Colombia, Venezuela, Brazil, Ecuador, Peru, Bolivia, intro Cuba, Puerto Rico, Leeward & Windward Is., Venezuelan Antilles, and Trinidad-Tobago; Psilanthele monospecific endemic of Ecuador; Pulchranthus 4 N SAM endemic spp. of Colombia, Venezuela, N Brazil, Suriname, French Guiana, Ecuador, Peru, and Bolivia; Rhombochlamys monospecific endemic of Colombia; Ruellia ~300 spp. native to CAM, Bahamas, Turks-Caicos, Aruba, Antilles (exc. Netherlands Antilles), Trinidad-Tobago, SW Caribbean, Galapagos, and tropical SAM S to N Argentina (exc. N Chile); Ruspolia 1 sp. intro to Trinidad-Tobago; Salpixantha monospecific endemic of Jamaica; Samuelssonia  monospecific endemic of Haiti; Sanchezia 55 former neoendemic spp. native to Panama, Colombia, Venezuela, N Brazil, Ecuador, Peru, and Bolivia, and now intro to Guatemala, Belize, El Salvador, Honduras, Nicaragua, Costa Rica, Antilles (exc. Cayman Is, Netherlands Antilles), and Trinidad-Tobago; Sapphoa 2 spp. endemic genera of Cuba; Schaueria 15 former endemic to C+E+S Brazil, but 1 sp now intro in Trinidad-Tobago; Sebastiano-schaueria monospecific endemic of SE Brazil; Spathacanthus 3 of 4 Mexico & CAM endemic spp. native to Guatemala, Honduras, and Costa Rica, including 1 narrow endemic of Costa Rica; Stenandrium 50 Americas endemic spp native from S USA to Nicaragua (exc. Belize), plus Bahamas, Turks-Caicos, Cuba, Hispaniola, Puerto Rico, Leeward & Windward Is., and tropical SAM S to C Chile, N Argentina (exc. Guyana, Suriname, French Guiana, N Chile); Stenostephanus 95 Mexico + neoendemic spp. native from Mexico S through CAM (exc. Belize, El Salvador) to Colombia, Venezuela, N+SE Brazil, Ecuador, Peru, and Bolivia; Streblacanthus 3 Mexico & N neoendemic spp. native to Guatemala, Costa Rica, Panama, Peru, and N Brazil; Strobilanthes 1 sp. intro to Belize, El Salvador, Honduras, Nicaragua, Panama, Cuba, Hispaniola, Jamaica, Puerto Rico, Windward Is, Venezuelan Antilles, and Trinidad-Tobago; Suessenguthia 8 N SAM endemic spp. of N Brazil, Peru, and Bolivia; Tessmanniacanthus monospecific endemic Peru?; Tetramerium 9 sub & tropical Americas endemic spp. native to Guatemala, El Salvador, Honduras, Nicaragua, Panama, Venezuela, Colombia, Ecuador, Peru, and Bolivia, including 5 narrow endemics of Peru; Trichanthera 2 neoendemic spp. of Panama, Colombia, Venezuela, N Brazil, Guyana, Suriname, French Guiana, Ecuador, and Peru; Trichosanchezia monospecific endemic Peru; Xantheranthemum monospecific of endemic Peru. Avicennioideae: Avicennia 3 spp. native to CAM, Bahamas, Aruba, Turks and Caicos, Antilles, SW Caribbean, Trinidad-Tobago, Colombia, Venezuela, Guyana, Suriname, French Guiana, N, E, and S Brazil, Uruguay, Ecuador, and Peru. Nelsonioideae: Aymoreana monospecific narrow endemic of E Brazil; Elytraria 11 spp. native to CAM, Cuba, Haiti, Aruba, Trinidad-Tobago, and tropical SAM S to Peru, NW Argentina, C+SE Brazil, and intro to Galapagos and includes 9 narrow endemics of Cuba (6), Haiti, Peru, and Ecuador; Nelsonia 1 sp. intro to El Salvador, Honduras, Nicaragua, Panama, Puerto Rico, Colombia, Ecuador, French Guiana, Bolivia, and N+C+E Brazil; Staurogyne 28-30 spp. native from Nicaragua S to Colombia, Venezuela, Guyana, Suriname, French Guiana, Brazil, Bolivia, and Trinidad and Tobago. Thunbergioideae: Mendoncia ~74 spp. native to CAM (exc. El Salvador), Trinidad-Tobago, and tropical SAM S to Peru, Bolivia, Paraguay, and S Brazil; Thunbergia several spp. intro to Bahamas, Antilles (exc. Cayman Is., Netherlands Antilles), CAM (exc. Nicaragua), and tropical SAM S to N Argentina (exc. French Guiana, N Chile, and Uruguay).

Patagonia Genera Include:

Acanthoideae: Stenandrium 1 sp. native in Bio Bio in 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 (Unpublished). Plant Families of North America. This is where all of the family descriptions come from. Below should be most of my references for this, as well as my own personal observations of species in North America.
• Canadensys: Acadia University, Université de Montréal Biodiversity Centre, University of Toronto Mississauga, University of British Columbia. http://data.canadensys.net/explorer (accessed 2020 – current)
• Delta: Watson, L., and Dallwitz, M.J. (1992+). The Families of Flowering Plants: descriptions, illustrations, identification, and information retrieval. Version: 2nd May 2020. delta-intkey.com. Accessed spring through fall of 2020.
• Flora of North America. (1993+). https://floranorthamerica.org/Main_Page.
• 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+). 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 – present.
• USDA, NRCS. 2020. The PLANTS Database (http://plants.usda.gov, 2 June 2020). National Plant Data Team, Greensboro, NC, USA; accessed throughout the fall of 2020.
• WFO (2022): World Flora Online. Published on the Internet: http://www.worldfloraonline.org. Accessed Spring 2022 – current

My Current Plant Family Education Fundraiser

I am currently seeking funding to expand my website and SEO capabilities as I keep adding new families, and I am also looking to invest in a new macro lens, as I will soon be adding floral dissections to the families as they become available to me. You can donate to help support native plant education using the GoFundMe link, also at the bottom of the page.

Copyright Information

The information and the photos on this site are free to use for educational purposes, with proper attribution. For other uses, please contact me first.

You can cite this site as follows: Willis, Lyrae (2020+). Lyrae’s Nature Blog – Plant Families of North America. https://lyraenatureblog.com/. Accessed [Enter Date].