1. Araceae Juss.

    1. This family is accepted.

[FWTA]

Araceae, F.N. Hepper. Flora of West Tropical Africa 3:1. 1968

Habit
Herbs with watery, bitter or milky juice, with a tuberous or elongated rhizome, rarely woody and climbing
Leaves
Leaves solitary or few, sometimes appearing after the flowers, mostly radical, when cauline then alternate and distichous or spirally arranged, entire or variously divided, often hastate or sagittate, with a membranous sheath at the base
Flowers
Flowers small, arranged on a spadix enclosed in a spathe, bisexual or monoecious, the males in the upper part, females below, rarely dioecious
Perianth
Perianth present in the bisexual flowers or absent from the unisexual flowers
Androecium
Stamens hypogynous, 2-4-8, opposite the perianth-segments; anthers opening by pores or slits, free or united
Gynoecium
Ovules parietal, axile, basal or apical Ovary superior or immersed, 1-many-locular; style various or absent
Fruits
Fruit a berry, or coriaceous and rupturing, 1-many-seeded
Seeds
Seeds mostly with copious endosperm
[CATE]

CATE Araceae, 17 Dec 2011. araceae.e-monocot.org

General Description
ANATOMY : Calcium oxalate raphides and druses abundant, raphides always present, laticifers commonly present, either simple and articulated or more rarely anastomosing, trichosclereids present (most Monstereae, Spathiphylleae, rarely in Potheae), tannin cells common, resin canals sometimes present ( Culcasieae , Homalomeneae , Philodendreae). HABIT : evergreen to seasonally dormant herbs, perennial, sometimes gigantic, climbing or subshrubby hemiepiphytes, epiphytes, lithophytes, terrestrial, geophytes, helophytes, sometimes rheophytes, true aquatics, rarely free-floating ( Pistia). STEM : aerial and erect to climbing or creeping with very short (plant rosulate) to very long (plant scandent) internodes, or subterranean and consisting of a subglobose to depressed-globose tuber (sometimes turnip- or carrot-like or irregular in shape) or horizontal to erect rhizome; terrestrial plants and helophytes sometimes arborescent with massive stem and terminal rosette of leaves ( Xanthosoma , Alocasia , Montrichardi a, Philodendron) or arborescent with a pseudostem of petiole sheaths (large in Typhonodorum, small in many Arisaema); geophytes often with solitary leaf. SHOOT ORGANIZATION : the mature, flowering stem is almost always a sympodium composed of a series of articles, rarely the stem is monopodial ( Potheae , Heteropsideae); each article begins with a 2-keeled (except Orontioideae ) prophyll (= “first leaf”) followed by a series of leaves and terminates with an inflorescence; leaf number per article may be determinate or indeterminate, and from one or very few to very many; the leaves of each article normally consist of a mixture of foliage leaves with partially to fully developed blades and cataphylls (bract-like structures lacking blades); the sympodial leaf is that subtending the inflorescence and may be a foliage leaf or a cataphyll; the prophyll is almost always a cataphyll (except Orontioideae); subsequent articles (continuation shoots) normally arise at the second node below the spathe node (except Orontioideae); juvenile shoots and flagelliform branches are always monopodial; terminal inflorescences may be solitary or may form a floral sympodium of several inflorescences; the articles of floral sympodia normally consist of a single 2-keeled prophyll and an inflorescence; the subsequent article of a floral inflorescence normally arises in the axil of the preceding prophyll, i.e. at the first node below the spathe node. VEGETATIVE PROPAGATION : climbing hemiepiphytes frequently form flagelliform shoots, which are stolon-like branches with leaves reduced to small cataphylls and very elongated internodes, adapted to seek out new host trees; other adaptative forms are subterranean stolons (e.g. Spathiphyllum , Lasimorpha ) and tubercules (e.g. Dracontium), bulbils with recurved scales borne on specialized shoots ( Remusatia), bulbils on petioles ( Pinellia ternata) or leaf blade ( Amorphophallus bulbifer), or formation of new plants from abscissed leaflets ( Zamioculcadeae). ROOTS : always adventitious, primary root withering soon after germination, sometimes dimorphic (climbing hemiepiphytes) with anchor roots and larger feeder roots, sometime contractile roots present (geophytes), rarely roots very fleshy, water-storing ( Stylochaeton). LEAVES : usually spirally arranged, sometimes distichous; normally differentiated into petiole and expanded blade (except e.g. Gymnostachys, some Biarum spp.), usually glabrous, rarely pubescent, tomentose, villous or with small to large and complex trichomes or papillae (e.g. Philodendron squamiferum) on the petiole; ptyxis usually convolute, rarely involute (e.g. Anthurium sect. Pachyneurium , Lagenandra); blade and petiole often variegated or mottled with spots, bands, blotches or irregularly shaped patches and zones of various colours, usually shades and mixtures of green, yellow and silver. CATAPHYLLS : caducous, marcescent, deciduous or persistent, sometimes beautifully mottled and patterned (e.g. Arisaema, Asterostigma), when persistent sometimes a conspicuous feature of plant and either membranous or forming fibrous mass (e.g. many spp. of Anthurium, Philodendron). PETIOLE : often as long as or longer than blade, usually smooth, sometimes hairy, papillose, warty, spiny or aculate (e.g. Lasioideae), occasionally covered with large multicellular processes (e.g. Philodendron squamiferum ), rarely massively succulent and water-storing (e.g. Zamioculcas, Philodendron martianum), often geniculate (pulvinate) apically (e.g. Anthurium), basally or rarely centrally (e.g. Gonatopus boivinii); sheath normally well-developed, often at least half as long as entire petiole, sometimes ligulate apically, often very reduced in sympodial leaves (especially in Anthurium, most Philodendron spp.). LEAF BLADE : simple to compound, extremely variable in shape :- rarely filiform (e.g. Cryptocoryne consobrina), linear ( Jasarum), most commonly elliptic, ovate, oblong, sagittate, hastate, less commonly trifid to trisect, pedatifid to pedatisect, radiatisect, dracontioid (i.e. trisect with each primary division further much divided), pinnatifid to pinnatisect ( Zamioculcas), bipinnatifid, tripinnatifid to quadripinnatifid ( Gonatopus), fenestrate ( Monstera) or laciniate (i.e. fenestrate with slit-like holes, Cercestis mirabilis); heteroblasty frequent, especially in climbing hemiepiphytes, “shingle leaves” (very short petiole, broad blade, adjacent blades partly overlapping like tiles) sometimes formed (e.g. some Potheae, some Monstereae); seedling leaves usually entire when epigeal, rarely first foliage leaf compound ( Gonatopus, Amorphophallu s). LEAF VENATION : midrib almost always differentiated, sometimes massive and succulent (e.g. Philodendron crassinervium); primary veins usually arising pinnately from midrib (and then called primary lateral veins), either running into marginal vein (e.g. Philodendron, Dieffenbachia ) or joining distally to form a submarginal collective vein on each side (e.g. Caladium, many Anthuriu m spp.), sometimes primary veins all arising from petiole insertion and running arcuately into leaf apex (e.g. Orontiu m, Anthurium sect. Digitinervium), rarely strictly parallel ( Gymnostachys) or subparallel ( Pistia), sometimes not differentiated at all (e.g. Philodendron crassinervium); secondary and tertiary veins either reticulate (e.g. Areae), or parallel-pinnate, i.e. running parallel to primaries (e.g. Philodendron), or arising from primaries at a wide angle and then arching strongly towards leaf margin (e.g. Colocasia), sometimes forming sinuous or zig-zag interprimary veins (e.g. Caladieae); higher order venation reticulated or forming cross connections between lower order veins. INFLORESCENCE : terminal, solitary, or 2 to many in a synflorescence, usually appearing to be axillary to sympodial leaf, consisting of a spadix (spike) of small flowers, subtended by a spathe (bract), usually erect, sometimes pendent (e.g. Anthurium wendlingeri , Stenospermation , Piptospatha), sometimes becoming pendent after anthesis (e.g. Typhonodorum). PEDUNCLE : very short to very long, usually similar to petiole in appearance, coloration, pubescence or armature, normally longer than spadix stipe, sometimes ± suppressed and spadix stipe elongated ( Orontium , Lysichiton). SPATHE : nearly always conspicuous (except Gymnostachys, Orontium), very variable in shape and colour, simpler forms (e.g. many Anthurium spp.) often green, reflexed or spreading, more complex forms often showy and highly coloured, erect, usually either boat-shaped or constricted centrally to form a basal tube and an apical blade; tube may enclose the female zone of the spadix or both fertile zones or rarely the entire spadix (e.g. Cryptocoryneae), tube rarely much longer than blade (many Cryptocoryne spp.), tube margins usually convolute, sometimes connate (e.g. Sauromatum , Stylochaeton, Arisarum); blade usually erect and gaping, sometimes widely spreading, twisted, reflexed or rarely margins ± closed forming slit-like opening (e.g. most Lagenandra spp.); spathe constriction may lie between or above male and female zones or occur in two places (e.g. some Remusatia spp.); spathe entirely deciduous soon after anthesis (e.g. Monstereae), or tube persistent to fruiting and blade marcescent to deciduous after anthesis ( Caladieae, Colocasieae , Schismatoglottideae), or spathe entirely persistent until fruiting (e.g. Philodendron, Homalomena) or whole spathe gradually withering and rotting (most Areae). SPADIX : usually erect, often fleshy and relatively thick, sessile or shortly stipitate, rarely very long-stipitate (e.g. Lysichiton, Orontium , some Anthurium spp.), usually free, sometimes adnate basally (e.g. Hapaline , Dieffenbachia) or entirely ( Spathicarpa) to spathe, either ± uniform in appearance (flowers bisexual or monoclinous), or divided into distinct floral zones (flowers unisexual or diclinous), fertile zones contiguous or separated by sterile zones, female (pistillate) zone always basal and male (staminate) zone either apical or intermediate in position (except Spathicarpa), rarely bisexual flowers occur between male and female zones (e.g. Arophytea e); sterile zones may be basal, intermediate or apical or any combination of these, apical sterile zone usually known as a terminal appendix; rarely a single plant produces inflorescences bearing male flowers only, followed in later years by inflorescences bearing female flowers only, and vice versa (paradioecy, known only in Arisaema). FLOWERS : 2- to 3-merous (-mery often hard to detect in unisexual flowers), bisexual (monoclinous, hermaphrodite) or unisexual (diclinous), very small, protogynous, lacking floral bracts, usually numerous (except e.g. Pistia, Ambrosina), sessile (except Pedicellarum), usually densely arranged, sometimes laxly so (e.g. male flowers of Arisarum, female flowers of Dieffenbachieae); bisexual flowers with or without ( Calloideae, Monsteroideae) a perigone (perianth), unisexual flowers usually without a perigone (present in Zamioculcadeae, Stylochaetoneae) but sometimes including rudimentary organs representing modified sexual parts of the other sex (e.g. staminodes of female flowers in Dieffenbachia and Spathicarpeae , cup-like synandrodium in Arophyteae, pistillodes present in male flowers of e.g. Stylochaeton, Furtadoa, some Spathicarpeae spp., central stigmatoid body of the synandrium present in Taccarum and some Gorgonidium spp.). PERIGONE : composed of free (e.g. Anthurium) or partially connate (some Pothos spp.) tepals, or consisting of a single cup-like structure (e.g. Spathiphyllum cannifolium); when free, tepals 4 to 6 and imbricate in 2 whorls, membranaceous (e.g. Anadendrum) or more commonly thickened at least apically, truncate ( Zamioculcadeae) to cucullate ( Lasioideae). STAMENS (bisexual perigoniate, bisexual non-perigoniate, unisexual perigoniate flowers): usually free (filaments connate in Gonatopus and often in Lasimorpha), equal in number and opposite to tepals (when present), rarely more (e.g. some Dracontium spp.); filaments distinct, often ± oblong and flattened (e.g. Anthurium), rarely filiform ( Stylochaeton), usually rapidly elongating to push anthers above perigone or gynoecium at anthesis; anthers usually terminal, basifixed, extrorse (introrse in Zamioculcas), always composed of 2 thecae each with 2 microsporangia; connective usually slender, inconspicuous, often overtopped by thecae, thecae dehiscing by single longitudinal slit or apical stomial pore, with all intermediate degrees occurring. MALE FLOWER (unisexual non-perigoniate flowers) : 1-8 androus (rarely more, e.g. Alocasia brisbanensis), floral grouping of stamens sometimes obvious in mature inflorescence (e.g. many Philodendron and Homalomena spp.) often obscured during ontogeny; stamens free or partially to completely connate to form a synandrium. FREE STAMENS (unisexual non-perigoniate flowers) : usually sessile to subsessile, filament sometimes distinct (e.g. Schismatoglottis), connective sometimes ± slender (e.g. Areae) but often strongly thickened, apically broad, fleshy and probably osmophoric (e.g. Philodendron), thecae lying opposite or adjacent on one side of stamen, dehiscing by single longitudinal slit or apical stomial pore, with all intermediate degrees occurring, rarely both microsporangia dehiscing independently by separate stomial pores (some Amorphophallus spp.), rarely theca produced apically into a horn dehiscing by single pore ( Cryptocoryneae, some Schismatoglottideae). SYNANDRIUM (unisexual non-perigoniate flowers) : usually ± sessile, sometimes formed by fusion of filaments only (e.g. Arisaema, Arisarum, Carlephyton sect. Pseudocolletogyne , Gorgonidium), more commonly composed of completely connate stamens and then usually apically truncate and ± prismatic in apical cross-section (e.g. Caladieae), sometimes mushroom-shaped ( Asterostigma) or cylindric ( Taccarum), very rarely ( Ariopsis) the synandria themselves connate; common connective usually broad, fleshy and probably osmophoric (e.g. Caladieae, Alocasia); thecae either lateral, apical or marginal depending on the degree of elongation of the thecae and the extent to which they are overtopped by the common connective, dehiscing by single longitudinal slit or apical stomial pore, with all intermediate degrees occurring. POLLEN : shed in monads, very rarely shed in tetrads ( Xanthosom a, Chlorospatha), aperturate in most bisexual-flowered genera, inaperturate in most unisexual-flowered genera, exine various (see chapter 9). STERILE ORGANS (pistillodes, staminodes, synandrodes) : often forming zones between fertile zones, sometimes present below female zone ( Monstereae, Schismatoglottideae), or on base on terminal appendix, very variable in shape, most often ± truncate and prismatic (e.g. Philodendron), more rarely filiform, subulate, bristle-like or elongate-clavate ( Areae), spathulate ( Bucephalandra), cylindric ( Aridarum) or enlarged and pearl-like ( Amorphophallus margaritifer ). TERMINAL APPENDIX : present only in some genera (e.g. Thomsonieae , Areae), probably always osmophoric, partly or completely (e.g. Pseudodracontium) covered with staminodes, rugose or corrugated or entirely smooth (e.g. most Areae), intermediate conditions also occur (e.g. Ulearum). FEMALE FLOWER (unisexual, non-perigoniate flowers) : Gynoecium sometimes surrounded by a whorl of variously shaped staminodes (e.g. Dieffenbachia, Spathicarpeae), or sometimes ± regularly associated with a single clavate staminode (e.g. Homalomeneae , Schismatoglottis). GYNOECIUM (bisexual and unisexual flowers) : ovary usually 1-3 locular, rarely more (e.g. Philodendron, most Spathicarpeae), 1-locular ovaries probably always pseudomonomerous; ovules 1-many per locule, orthotropous, hemiorthotropous, campylotropous, amphitropous, hemianatropous or anatropous; placenta 1-several, axile, parietal, apical, basal, or basal and apical; stylar region (tissue lying between ovary and stigmatic epidermis) usually well-developed, usually at least as broad as ovary, sometimes attenuate and elongate (e.g. many Amorphophallus, Arisaema, Biarum spp., Dracontium, some Spathiphyllum spp.) or massive and truncate (most Monstereae spp.), rarely dilated and connate with those of neighbouring gynoecia ( Xanthosoma); stigma hemispheric, capitate, discoid, umbonate, more-or-less strongly lobed (e.g. some Amorphophallus, Dieffenbachia spp.), rarely stellately lobed ( Asterostigma), sometimes brightly coloured (e.g. some Alocasia, Amorphophallus spp.), always wet from copious stigmatic secretion during at female anthesis, sometimes producing conspicuous nectar droplet (e.g. Anthurium). FRUIT : normally a juicy berry, rarely mesocarp leathery; berries normally free, rarely connate ( Syngonium) or connate and dehiscent as a syncarp ( Cryptocoryne), usually red, orange or purplish red, sometimes white (e.g. some Philodendron spp., Stenospermation), yellow ( Typhonodorum), green ( Arophyton buchetii , Lysichiton, Orontium , Peltandra virginica), very rarely blue ( Amorphophallus kerrii , Gymnostachys), or brownish ( Jasarum); infructescence densely packed, cylindric to globose, exposed by withering, basal abscission (e.g. Philodendro n) or splitting (e.g. Alocasia, Dieffenbachia) of spathe, rarely berries dehiscent, either basally ( Lagenandra) or apically with the seeds exposed by ± simultaneous sloughing of stylar regions of all berries (e.g. Monstereae). SEED : 1-many per berry; testa thick to thin, smooth, roughened, verrucose or striate-costate, papery in seeds with highly developed embryos ( Gonatopus, Nephthytis), sometimes decaying at maturity ( Orontium), or lacking altogether ( Gymnostachys), sometimes arillate with a conspicuous strophiole (e.g. most Areae, Ambrosina), rarely operculate (e.g. Pistia); embryo usually straight, sometimes curved (e.g. Cyrtosperma , Epipremnum), usually undifferentiated, rarely with highly developed plumule (e.g. Cryptocoryne ciliata , Orontium , Typhonodorum) and then endosperm lacking and outer cell layers of embryo chlorophyllous; endosperm abundant or absent, with all intermediate states occurring.
[FTEA]

Araceae, S.J. Mayo. Flora of Tropical East Africa. 1985

Habit
Herbs, perennial, terrestrial, epiphytic or aquatic, often with milky, viscid or acrid sap; stems lianescent, tuberous, rhizomatous or reduced
Leaves
Leaves alternate, 1–many, petiolate, usually some reduced to scale leaves (cataphylls) before or among normal leaves or inflorescences; petiole typically with distinct basal sheath, often pulvinate at or near apex; lamina usually broad, membranous to coriaceous, very variable in size and shape, simple or variously lobed, sometimes perforated; main venation pinnate, palmate, pedate or rarely parallel, finer venation reticulate or striate
Inflorescences
Inflorescence pedunculate, consisting of fleshy ± cylindric spadix (spike) subtended by bract-like spathe; spathe usually spreading above and convolute below, rarely with margins connate near base, often variously coloured; spadix either uniform with bisexual flowers or monoecious with pistillate flowers at base, staminate flowers above, sterile flowers of varying shape often present at base, middle or apex, apical portion sometimes forming a sterile appendix
Flowers
Flowers numerous, minute, sessile, bractless, naked or perigoniate, bisexual or unisexual; perigon (perianth) cup-like or composed of 4–9 free or ± connate tepals
Androecium
Stamens opposite tepals, free or connate into synandria; anthers sessile or with elongated filaments, opening by lateral or apical slits or pores; connective often very thick
Gynoecium
Ovary normally superior, 1–many-locular; locules each with 1–many ovules; placentas parietal, axile, basal or apical; stigma sessile or borne on short, conical, rarely attenuate style
Fruits
Fruit a 1–many-seeded berry, rarely connate to form a syncarp, often brightly coloured
Seeds
Seeds minute to large, variable in shape, with or without endosperm
[NTK]

Haigh, A. (2009). Neotropical Araceae.

Morphology
Description

Gigantic to minute herbs, terrestrial, epiphytic , hemiepiphytic or epilithic, rarely aquatic ( free -floating or rooted). Roots often aerial, in the Lemnoideae hair-like or absent. Stem aerial and erect (e.g. Dieffenbachia Schott and Rhodospatha Poepp.), creeping, subterranean and rhizomatous or tuberous (e.g. Caladium Vent. and Homalomena Schott), or appressed -climbing, frequently scandent, rarely erect , hardened, and armed (Montrichardia Crueg.), or not differentiated into stem or leaf (Lemnoideae), in this case the plant is reduced to a minute, fleshy or flattened plant body bearing hair-like roots on the undersurface or roots absent. Cataphylls often variously ribbed and persistent , may remain intact or weather into fibres. Leaves alternate , sometimes distichous , simple , basal or cauline, rarely solitary (e.g. Dracontium L.); petioles often elongate, sheathed at least basally, the apex often geniculate, blades often variegated , often oblong , cordate , sagittate to hastate , sometimes perforated, the margins entire , or pinnately to palmately lobed , main veins often radiate from petiole attachment , rarely parallel, the primary lateral veins (in some families referred to as secondary veins ) pinnate , sometimes joining into collective veins along margins, the lesser veins parallel or reticulate . Inflorescences terminal or axillary , solitary or clustered in axils, an unbranched spadix ( spike ) subtended by a single spathe ( bract ), in Lemnoideae the inflorescence is within a minute dorsal cavity of the plant body (Wollfia Horkel ex Schleid., Wolffiella Hegelm.), or in paired lateral budding pouches (Spirodela Schleid., Landoltia Les & D.J. Crawford, Lemna L.); spathe herbaceous , free or adnate to spadix , spreading, reflexed or convolute, sometimes constricted below middle and differentiated into tube below and blade above, often persistent , sometimes (especially when convolute) reclosing over spadix after anthesis, the blade sometimes deciduous , green, or blade and tube of spathe differently coloured; spadix often cylindric, flowers dense, the lower part often pistillate, this part often protected by accrescent spathe tube until maturity of fruits, some parts with sterile flowers or without flowers, the upper part often staminate, this part (e.g. Syngonium Schott and Xanthosoma Schott) often caducous , the apex frequently tapered, less often clavate or ellipsoidal. Flowers sessile , small, bisexual or unisexual (the plants usually monoecious ), 2-3- merous , protogynous, lacking floral bracts; perianth (=perigone) lacking in unisexual flowers; tepals 4-6, usually free , rarely united; androecium of (1-)3-6(-9) stamens, the stamens free or united into synandria, the thecae terminal or lateral , extrorse, dehiscent by longitudinal slits or apical pores; staminodes sometimes present, free or united into synandria; gynoecium syncarpous, the ovary usually superior , sessile or immersed in the spadix , often entire , rarely lobed , usually 1-3 locular, rarely more, the style usually inconspicuous, the stigma wet at anthesis, sometimes distinctly lobed ; placentation axile , parietal or basal , the ovules 1-many per locule , often with funicle, less often sessile< /A> . berry -like, sometimes juicy, free or rarely fused into syncarps (Syngonium), often colourful, rarely utricles (Lemnoideae); seeds 1-many; endosperm copious to absent.

Distribution
Distribution in the Neotropics

48 genera (including five introduced), ca. 3200 species worldwide.

  • Alloschemone Schott (2 species) - northern Brazil to Bolivia.
  • Alocasia (Schott) G. Don (77 species) - Old World tropics. A. cucullata (Lour.) G.Don and A. macrorrhizos (L.) G.Don are naturalized in the Neotropics.
  • Anaphyllopsis A.Hay (3 species) - tropical South America.
  • Anthurium Schott (c. 1000 species) - throughout Neotropics.
  • Asterostigma Fisch. & C.A.Mey (8 species) - Brazil to NE Argentina.
  • Bognera Mayo & Nicolson (1 species) - northern Brazil.
  • Caladium Vent.(12 species) - from Costa Rica to northern Argentina.
  • Chlorospatha Engl. (23 species) - Central America and western South America.
  • Colocasia Schott (16 species) - tropical Asia, Malay Archipelago. Colocasia esculenta (L.) Schott is cultivated and naturalized throughout the tropics.
  • Croatiella E.G.Gonç. (1 species) - Ecuador.
  • Dieffenbachia Schott (57 species) - Mexico through Central America to western and central South America, also in West Indies.
  • Dracontioides Engl. (2 species) - eastern Brazil.
  • Dracontium L. (24 species) - from Nicaragua south to Paraguay and southern Brazil, also in Trinidad.
  • Epipremnum Schott (15 species) - tropical Asia, western Pacific and North and Northeast Australia. E. aureum (Linden & André) G.S.Bunting widely cultivated and naturalized, E. pinnatum (L.) Engl. naturalized in parts of the Caribbean.
  • Filarum Nicolson (1 species) - Peru.
  • Gearum N.E.Br. (1 species) - central Brazil.
  • Gorgonidium Schott (7 species) - Peru to northern Argentina.
  • Heteropsis Kunth (14 species) - Central and South America (with a disjunct between the Amazon basin and the Brazilian Atlantic Forest Zone).
  • Homalomena Schott (107 species) - tropical Southeast Asia, Malay Archipelago, 11 species in Neotropics.
  • Incarum (1 species) - Ecuador to Bolivia.
  • Jasarum G.S.Bunting (1 species) - northern South America.
  • Landoltia Les & D.J.Crawford (1 species) - pantropical and subtropical.
  • Lemna L. (13 species) - cosmopolitan, 8 species in Neotropics.
  • Mangonia Schott (2 species) - southern Brazil to Uruguay.
  • Monstera Adans. (38 species) - Mexico to Bolivia and Brazil.
  • Montrichardia Crueg. (2 species) - Central America, northern South America and West Indies.
  • Philodendron Schott (c. 750 species) -throughout Neotropics.
  • Pistia L. (1 species) - pantropical and subtropical.
  • Rhodospatha Poepp. (27 species) - Mexico and Central America to Bolivia and eastern Brazil.
  • Scaphispatha Brongn. ex Schott (2 species) - Bolivia to Brazil.
  • Schismatoglottis Zoll. & Moritzi (106 species) - tropical & subtropical Asia, South West Pacific, 3 species in tropical South America.
  • Spathantheum Schott (2 species) - Peru to northern Argentina.
  • Spathicarpa Hook. (4 species) - tropical South America.
  • Spathiphyllum Schott (49 species) - western Pacific, Malesia. 43 species in the Neotropics.
  • Spirodela Schleid. (3 species) - cosmopolitan, 2 species in the Neotropics.
  • Stenospermation Schott (45 species) - tropical Central and South America.
  • Synandrospadix Engl. (1 species) - Peru to Northwest Argentina.
  • Syngonium Schott (33 species) - Mexico to tropical America.
  • Taccarum Brongn. (6 species) - tropical South America to northern Argentina.
  • Typhonium Schott (72 species) - tropical Africa, Arabian Peninsular to Mongolia and Australia. T. roxburghii Schott naturalized in the Neotropics.
  • Ulearum Engl. (2 species) - Peru, northern Brazil.
  • Urospatha Schott (12 species) - Central and Southern tropical America.
  • Wolffia Horkel ex Schleid. (11 species) - cosmopolitan, 5 species in Neotropics.
  • Wolffiella Helgelm. (10 species) - America, Africa, 5 species in Neotropics.
  • Xanthosoma Schott (71 species) - Mexico and Cuba to southern Brazil and northern Argentina.
  • Zantedeschia  Spreng. (8 species) - Africa; Z. aethiopica (L.) Spreng. cultivated and naturalized in the Neotropics.
  • Zomicarpa Schott (3 species) - Brazil.
  • Zomicarpella N.E.Br. (2 species) - Colombia, Peru, Northern Brazil.
General Description
Number of genera

See above

Status
  • Native, cultivated, naturalized and endemic taxa are found.
General notes
  • Several Aroids are cultivated for their edible tubers and leaves. These include Colocasiaesculenta (L.) Schott, Xanthosomasagittifolium (L.) Schott and some species of Amorphophallus Blume ex Decne. 
  • Some species are also used in folk medicines and as a source of fibre.
  • Aroids are widely used as ornamental plants across the world, both as house plants ands garden plants especially in the tropics.
Notes on delimitation
  • The Araceae family is placed in the Alismatales together with Alismataceae and Potamogetonaceae in the Neotropics.
  • In the APG system the Araceae include the duckweeds in the subfamily Lemnoideae (formerly in a separate family Lemnaceae).
Diagnostic
Useful tips for generic identification
  • Observe venation pattern.
  • Are the flowers bisexual or unisexual?
  • Observe spathe shape, fusion to the spadix and persistence.
  • Observe presence/absence of spadix appendix.
  • Observe habit.
  • Observe leaf shape.
  • Observe presence/absence of trichosclereids.
Notable genera and distinguishing features

Anthurium:

  • The largest genus with about 1,000 species.
  • Usually an epiphyte or climbing hemiepiphyte, less often lithophyte or terrestrial.
  • Stem aerial, not tuberous or rhizomatous.
  • Petiole geniculate at apex; higher order leaf venation clearly reticulated, submarginal collective veins usually present, tissues without trichosclereids.
  • Flowers bisexual, with obvious perigone of four free tepals.
  • Spathesimple, spreading, reflexed or erect.
  • Spadix uniform in appearance with flowers of only one type.
  • Berries.
  • Throughout the Neotropics.

Philodendron:

  • About 750 species.
  • Small to gigantic.  Mostly climbing hemiepiphytes or epiphytes, sometimes arborescent to rhizomatous terrestrials.
  • Leaves with abundant resin canals.
  • Leaf blade very variable in shape, from linear to bipinnatifid, trisect or pedatisect, lacking a submarginal collective vein, fine venation parallel-pinnate.
  • Inflorescence secreting resin from spathe or spadix at anthesis.
  • Flowers unisexual, perigone absent.
  • Ovary usually 4-8-locular (extreme range 2 to 47-locular).
  • Ovules usually hemiorthotropous.
  • Placentaaxile to basal.
  • Differs from Anthurium in unisexual flowers without perigone, and parallel-pinnate fine venation.
  • Throughout the Neotropics.
Distinguishing characters (always present)
  • Herbs.
  • Inflorescence almost always consisting of small sessile flowers densely congested into spadix (spike) subtended by a spathe (bract).
  • Flowers lack floral bract.
  • Leaves alternate.
Other important characters
  • Aerial roots often present.
  • Fruit usually berries.
  • Leaves petiolate.
Literature
Important literature

Bown, D. 2000. Aroids. Plants of the Arum family. 2nd edn. 392 pp. Timber Press, Portland, Oregon.

Govaerts, R. & Frodin, D.C. 2000. World Checklist and Bibliography of Araceae (and Acoraceae). 560 pp. Kew: Royal Botanic Gardens.

Mayo, S. J., Bogner, J. & Boyce, P.C. 1997. The Genera of Araceae. xii, 370 pp., Kew: Royal Botanic Gardens.

Croat, T.B. 1991. A revision of Anthurium section Pachyneurium (Araceae). Ann. Missouri Bot. Gard. 78(3): 539-855.

Croat, T.B. 1997. A revision of Philodendron subgenus Philodendron (Araceae) for Mexico and Central America. Ann. Missouri Bot. Gard. 84: 314-704.

Haigh, A., Mayo, S.J., Croat, T.B., Clark B.R. (2007). CATE ARACEAE version 0.7. Published on the internet at www.cate-araceae.org on 28 November 2008. Includes interactive keys to genera, and species of Anthurium and Philodendron.

International Aroid Society http://www.aroid.org.

Landolt, E. 1986. The family of Lemnaceae: a monographic study (vol. 1). Ver. Geobot. Inst. E.T.H., Stiftung Rübel 71: 1-566.

[FWTA]

Lemnaceae, F.N. Hepper. Flora of West Tropical Africa 3:1. 1968

Habit
Small to minute floating or submerged herbs without roots or roots simple and thread-like, capped
Flowers
Flowers monoecious, naked or at first enclosed in a membranous sheath Female flowers: ovary sessile, 1-locular; style and stigma simple; ovules 1-7 Male flowers: stamens 1-2, with slender filaments or the latter thickened in the middle or absent; anthers 1-2-locular
Perianth
Perianth absent
Male
Male flowers: stamens 1-2, with slender filaments or the latter thickened in the middle or absent; anthers 1-2-locular
Female
Female flowers: ovary sessile, 1-locular; style and stigma simple; ovules 1-7
Seeds
Seeds with fleshy or no endosperm; embryo straight, axile
[FTEA]

Lemnaceae, F. N. Hepper. Flora of Tropical East Africa. 1973

Habit
Aquatic herbs, floating or submerged and freely drifting, very reduced in structure to a flat or curved thallus or suborbicular, often minute; stems and leaves undifferentiated
General
Vascular tissue minimal
Roots
Roots present or absent, often solitary, suspended in the water, devoid of root hairs, tip covered by a cap
Vegetative Multiplication
Vegetative reproduction usual, daughter thallus budding from a lateral pocket, often remaining attached to parent; resting buds (turions) sometimes produced in adverse conditions
Flowers
Flowering erratic; flowers monoecious; developing in a pouch or pit, enclosed by a spathe or spathe absent Staminate flowers 1–2; anthers 2-thecous Pistillate flower solitary; style short; stigma concave; ovules 1–6
Male
Staminate flowers 1–2; anthers 2-thecous
Female
Pistillate flower solitary; style short; stigma concave; ovules 1–6
Seeds
Seeds ellipsoid, usually ribbed; endosperm scanty or none

Images

Araceae Juss. appears in other Kew resources:

First published in Gen. Pl. [Jussieu] 23. 1789 [4 Aug 1789] (1789)

Accepted by

  • APG IV (2016) http://dx.doi.org/10.1111/boj.12385

Literature

CATE Araceae
  • Mayo, S.J., Bogner, J. & Boyce, P.C. 1997. The genera of Araceae. 370 pp.

Sources

CATE Araceae
Haigh, A., Clark, B., Reynolds, L., Mayo, S.J., Croat, T.B., Lay, L., Boyce, P.C., Mora, M., Bogner, J., Sellaro, M., Wong, S.Y., Kostelac, C., Grayum, M.H., Keating, R.C., Ruckert, G., Naylor, M.F. and Hay, A., CATE Araceae, 17 Dec 2011.
http://creativecommons.org/licenses/by-nc-sa/3.0

Flora of Tropical East Africa
Flora of Tropical East Africa
http://creativecommons.org/licenses/by-nc-sa/3.0

Flora of West Tropical Africa
Flora of West Tropical Africa
http://creativecommons.org/licenses/by-nc-sa/3.0

Kew Names and Taxonomic Backbone
The International Plant Names Index and World Checklist of Selected Plant Families 2018. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
© Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

Neotropikey
Milliken, W., Klitgard, B. and Baracat, A. (2009 onwards), Neotropikey - Interactive key and information resources for flowering plants of the Neotropics.
http://creativecommons.org/licenses/by/3.0