1. Arecaceae Bercht. & J.Presl

    1. This family is accepted.

[FTEA]

Palmae, John Dransfield. Flora of Tropical East Africa. 1994

Leaves
Leaves usually with a well-defined sheathing base (in some species forming a columnar pseudostem above the trunk - crownshaft); petiole sometimes very short or absent, variously armed or unarmed; lamina pinnate, bipinnate, palmate, costapalmate or simple plicate; in some climbing palms the rachis elongated into a barbed whip (cirrus), sometimes also armed with reflexed spine-like leaflets (acanthophylls); leaflets either induplicate or reduplicate, very rarely mixed, compound (composed of more than one fold) or simple (composed of single folds); in most palmate and costapalmate leaves a ligule-like structure (hastula) present adaxially at the base of the lamina, sometimes also present abaxially; leaflet margins entire or erose (praemorse), armed or unarmed
Habit
Plants hermaphrodite, polygamous, monoecious or dioecious, hapaxanthic or pleonanthic Trees to shrublets, and climbers, armed or unarmed; stems woody, very short (hence acaulescent) to immensely tall, sometimes climbing, solitary or clustered, smooth or covered with leaf-base remains or leaf-sheaths, usually prominently ringed with leaf-scars, occasionally ventricose, usually unbranched except at the base, very rarely branching aerially in a sympodial manner or by equal forking (dichotomy) or anomalously
Inflorescences
Inflorescences axillary, usually single, occasionally grouped, interfoliar, infrafoliar or aggregated in a terminal mass, but here inflorescence units still axillary in axils of reduced leaves or bracts, very rarely (some Calamus spp.) some inflorescences also sterile and modified as barbed climbing organs (flagella), adnate to the internode and sheath of the leaf above; inflorescence often extremely complex with branching up to 5 orders, occasionally spicate, usually built up of a basic pattern consisting of an axis bearing a prophyll and bracts, the prophyll and 0–several of the bracts usually empty, the others each subtending a branch, in turn bearing a prophyll and bracts subtending a further order of branches and so on; ultimate branches (rachillae) bearing bracts subtending flowers, singly or in pairs, triads, or small groups, the whole flower group representing a condensed branching system (cincinnus)
Flowers
Flowers hermaphrodite, male, female or sterile male (accolyte flowers of pistillate inflorescences in >i>Calamus); calyx and corolla sometimes very similar, sometimes highly differentiated, with fused or free segments, usually rather small, variously coloured (green, cream, white, yellow, rose, violet), usually but not always in whorls of 3; stamens free or united, 3–many, usually in whorls of 3, 6 or 9; anthers basi- or dorsifixed, straight or twisted; staminodes often present in pistillate flowers; gynoecium apocarpous with 1–3 (or rarely more) carpels, or syncarpous with 3 or rarely more locules, or pseudomonomerous with 1 fertile and 2 abortive locules; stigmas erect or recurved; ovule 1 only in each carpel or locule, anatropous, hemianatropous, campylotropous or orthotropous, attached basally, laterally or apically; pistillode often present in staminate flowers
Fruits
Fruit usually 1-seeded, more rarely 2–10-seeded, ranging from minute to extremely large; stigmatic remains borne basally, laterally or apically; epicarp dull or brightly coloured, smooth, hairy, spiny, corky-warted or covered in reflexed imbricate scales; mesocarp fleshy, fibrous or dry, often fragrant, sometimes with copious irritant needle-crystals; endocarp well developed to absent
Seeds
Seed either closely adhering to the endocarp or free, sometimes with a well-developed sarcotesta; endosperm ruminate or homogeneous; embryo basal, lateral or apical
Germination
Germination remote-tubular, remote-ligular or adjacent-ligular; seedling leaves simple or compound
[FWTA]

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

Habit
Stems stout or slender, sometimes climbing, sometimes very short or almost nothing, often covered by the persistent bases of the leaves; primary root soon disappearing and replaced by roots from the base of the stem
Leaves
Leaves in a terminal cluster or in the climbing species scattered, sometimes very large, entire, pinnately or digitately divided, the segments or leaflets folded induplicately or reduplicately in bud, often sharp at the apex and prickly on the margins or midrib; rhachis often expanded at the base into a fibrous sheath
Flowers
Flowers small, actinomorphic, bisexual, monoecious or dioecious, sometimes polygamous, arranged in an often paniculate inflorescence (spadix) either amongst or below the leaves
Inflorescences
Spathes various, sometimes numerous and enclosing the peduncle and branches of the inflorescence, or few, leathery or membranous; bracteoles often connate below the flowers
Perianth
Perianth double
Calyx
Sepals 3, separate or connate, imbricate or open in bud
Corolla
Petals 3, separate or connate, usually valvate in the male flowers and imbricate in the female
Androecium
Stamens usually 6, in two series, rarely numerous; anthers 2-locular, loculi globose to linear, opening by slits lengthwise; pollen smooth or rarely echinulate
Gynoecium
Ovary superior, rudimentary or absent in the male flowers, 1-3 locular, rarely 4-7 locular, or carpels 3 and distinct or connate only at the base; ovule solitary and erect or pendulous from the inner angle of each carpel or loculus of the ovary
Fruits
Fruit a berry or drupe, 1-2-locular, or fruiting carpels distinct; exocarp often fibrous, sometimes covered by reflexed scales
Seeds
Seeds free or adherent to the endocarp; endosperm present, sometimes ruminate; embryo small
[NTK]

Baker, W.J. (2009). Neotropical Arecaceae.

Morphology
Description

Massive to minute woody monocotyledonous plants; trees, shrubs or climbers , sometimes fiercely spiny . Stems clustered or solitary, erect , creeping or climbing, often massive, sometimes very short and/or subterranean and thus appearing to be absent; usually marked with conspicuous nodal rings (leaf scars), sometimes dying after flowering. Aerial stems usually unbranched, but a few notable species branch by equal forking and other species branching anomalously. Leaves compound , less frequently entire ; compound leaves derived by splitting of an initially entire lamina , pinnate , bipinnate or palmate . Lamina almost always conspicuously folded. Leaf bases always tubular and sheathing (at least in the bud ), often forming conspicuous tubular crownshaft. Inflorescences always lateral , often massive, spicate to paniculate, sometimes aggregated in a mass of inflorescences held above leaves resulting in death of  stem . Flowers: bisexual or unisexual ( monoecious or dioecious ), mostly following basic monocot ground plan (3+3+6+3), but with many exceptions, particularly in stamen number (e.g. over 1000 stamens in Phytelephas Ruiz & Pav.); calyx and corolla distinguishable, often inconspicuous, but some colourful and enlarged; ovary always superior , always one ovule per carpel . Fruit berry or drupe ; minute to massive, usually 1-3 seeded, often brightly coloured, sometimes scaly or spiny .

Distribution
Distribution in the Neotropics
  • Widespread in Neotropics, especially in rainforest.
  • For generic distributions see www.palmweb.org or literature below.
Diagnostic
Distinguishing characters (always present)
  • Distinctive palm habit comprising narrow, columnar, unbranched stem with crown of palmate of pinnate leaves. [Not in climbers, acaulescent or prostrate species].
  • Stem with distinctive ring scars.
  • Leaves usually pinnate or palmate.
  • Unique leaf structure and development - the lamina is plicate (folded), although in some species flattens with maturity. The compound leaf morphology is achieved by splits forming along the folds, resulting in pinnate or palmate leaves. [Lamina remains undivided in some species].
  • Leaf base forms a sheath.
Key differences from similar families

Rarely confused with other families except Cyclanthaceae.

  • Palms are never rootclimbers (some Cyclanthaceae are rootclimbers).
  • Palms do not have perianth parts in fours (Cyclanthaceaeperianth parts, where present, in fours).
  • Cyclanthaceae leaves do not develop like palm leaves.
  • Cyclanthaceae have distinctive inflorescence structure/organization (spicate, alternating male and female flowers) not found in palms.
Other important characters
  • Often spiny.
Useful tips for generic identification

Spiny/armed palms:

  • Acoelorraphe (petiole only)
  • Acrocomia
  • Aiphanes
  • Astrocaryum
  • Bactris
  • Brahea (teeth on petiole)
  • Copernicia (petiole)
  • Cryosophila (root spines on stem)
  • Desmoncus
  • Elaeis (petiole)
  • Mauritiella (root spines on stem)
  • Rhapidophyllum (leaf sheath spines)
  • Serenoa (teeth on petiole)
  • Trithrinax (leaflet tips, sheath fibre spines)
  • Washingtonia (teeth on petiole)
  • Zombia (sheath fibre spines).

Fan-leaved palms:

  • Acoelorraphe
  • Brahea
  • Chelyocarpus
  • Coccothrinax
  • Colpothrinax
  • Copernicia
  • Cryosophila
  • Hemithrinax
  • Itaya
  • Lepidocaryum
  • Leucothrinax
  • Mauritia
  • Mauritiella
  • Rhapidophyllum
  • Sabal
  • Schippia
  • Serenoa
  • Thrinax
  • Trithrinax
  • Washingtonia
  • Zombia

Climbing palms:

  • Desmoncus
  • Chamaedorea elatior

Stilt rooted palms:

  • Iriartella
  • Dictyocaryum
  • Iriartea
  • Socratea
  • Wettinia

Vegetable ivory palms:

  • Ammandra
  • Aphandra
  • Phytelephas  

Flowers emerging from pits:

  • Welfia
  • Pholidostachys
  • Calyptrogyne
  • Calyptronoma
  • Asterogyne
  • Geonoma

Fruitscaly (like reptile scales):

  • Mauritia
  • Mauritiella
  • Lepidocaryum
  • Raphia
Notable genera and distinguishing features
  • Ammandra, Aphandra, Phytelephas  - the vegetable ivory palms, tagua. Stemless to short-trunked pinnate-leaved palms of Andean forests and neighboring areas. Dioecious with short-lived inflorescences, the males elongate and comprising numerous reduced flowers with up to 1000+ stamens, the females congested and consisting of the largest of all palm flowers (up to c. 20 cm long). Fruits warty containing numerous seeds with hard ivory-like endosperm.
  • Astrocaryum  - viciously spiny stemless to canopy pinnate-leaved tree palms, leaf undersurface white.
  • Attalea - American oil palms, often massive tree palms with huge pinnate leaves, visible in agricultural lanscapes. 
  • Bactris - most species rich of the spiny genera, undergrowth to canopy pinnate-leaved palms (sometimes entire -leaved), includes the peach palm Bactrisgasipaes (pejibaye, chonta, pupunha).
  • Ceroxylon - the Andean wax palms - conspicuous in Andean forests, pinnate -leaved, often very tall, stems waxy.
  • Chamaedorea - most species rich palm genus in the Neotropics, most diverse in Central America, mostly slender understorey dioecious palms, pinnate- or entire-leaved, with flowers solitary (not in clusters) on the inflorescence branches.
  • Coccothrinax - most species rich fan-leaved genus in Neotropics, largely restricted to Caribbean islands and Central America, slender to moderate palms with leaves unarmed and petiole base not cleft.
  • Cocos - the coconut.
  • Desmoncus - spiny climbing palm with pinnate leaves, rattan-like.
  • Dictyocaryum, Iriartea, Socratea, Wettinia - important and often very common stilt-rooted canopy palm species, with pinnate, often plumose leaves. Particularly conspicuous in much of Amazonia and the humid forests of the Andes.
  • Euterpe - assai palms. Moderate to robust, solitary or clustering pinnate-leaved tree palms, leaf sheaths tubular and forming a cylinder (crownshaft). Inflorescence resembles a horse's tail.
  • Geonoma - most frequently encountered understorey palm genus in South America, mostly rather small, leaves pinnate or often entire. Inflorescences spicate or branches with flowers emerging from pits. Easily confused with related genera (e.g. Calyptrogyne, Calyptronoma, Asterogyne).
  • Mauritia - massive, solitary fan-leaved tree palm, often forming dominant stands in swampy areas. Moriche, buriti palms.
  • Oenocarpus - Moderate to very large pinnate -leaved palms with inflorescences similar to a horse's tail.
General Description
Number of genera

68 genera as follows:

  • Acoelorraphe  H.L.Wendl.
  • Acrocomia Mart.
  • Aiphanes Willd.
  • Allagoptera Nees
  • Ammandra O.F.Cook
  • Aphandra Barfod
  • Asterogyne H.Wendl. ex Benth. & Hook.f. 
  • Astrocaryum G.Mey.
  • Attalea Kunth
  • Bactris Jacq. ex Scop.
  • Barcella Drude
  • Brahea Mart.
  • Butia Becc.
  • Calyptrogyne H.Wendl.
  • Calyptronoma Griseb.
  • Ceroxylon Humb. & Bonpl.
  • Chamaedorea Willd.
  • Chelyocarpus Dammer
  • Coccothrinax Sarg.
  • Cocos L.
  • Colpothrinax Griseb. & H.Wendl.
  • Copernicia Mart
  • Cryosophila Blume
  • Desmoncus Mart.
  • Dictyocaryum H.Wendl.
  • Elaeis Jacq. 
  • Euterpe Mart.
  • Gaussia H.Wendl.
  • Geonoma Willd.
  • Hemithrinax Hook.f. 
  • Hyospathe Mart.
  • Iriartea Ruiz & Pav.
  • Iriartella H.Wendl.
  • Itaya H.E.Moore
  • Juania (Juan Fernandez Islands) Drude
  • Jubaea Kunth
  • Leopoldinia Mart.
  • Lepidocaryum Mart.
  • Leucothrinax C.Lewis & Zona
  • Lytocaryum Toledo 
  • Manicaria Gaertn.
  • Mauritia L.f.
  • Mauritiella Burret
  • Neonicholsonia Damm.
  • Nypa (introduced) Steck
  • Oenocarpus Mart.
  • Parajubaea Burret 
  • Pholidostachys H.Wendl. ex Benth. & Hook.f.
  • Phytelephas 
  • Prestoea Hook.f.
  • Pseudophoenix H.Wendl.
  • Raphia P.Beauv. 
  • Reinhardtia Liebm.
  • Roystonea O.F.Cook
  • Rhapidophyllum (southeastern USA only) H.Wendl. & Drude
  • Sabal Adans.
  • Schippia Burret
  • Serenoa Hook.f.
  • Socratea Karst.
  • Syagrus Mart.
  • Synechanthus H.Wendl.
  • Thrinax L.f. ex Sw.
  • Trithrinax Mart. 
  • Washingtonia Raf.
  • Welfia H.Wendl.
  • Wendlandiella Dammer
  • Wettinia Poepp. ex Endl.
  • Zombia L.H.Bailey
General notes
  • Widespread and conspicuous throughout the region.
  • Easily identified and often persisting in converted landscapes.
  • The most important angiosperm family for resources extracted from the wild, unbeaten by any other family for its multiplicity of uses.
  • Some species domesticated, others cultivated on a commercial scale.
Status
  • Native.
  • Cultivated.
  • Naturalised.
  • Many genera endemic.
Literature
Important literature

DRANSFIELD, J., N.W. UHL, C.B. ASMUSSEN-LANGE, W.J. BAKER, M.M. HARLEY & C.E. LEWIS. 2008. Genera Palmarum - Evolution and Classification of the Palms. Royal Botanic Gardens, Kew.

HENDERSON, A. 1995. The palms of the Amazon. Oxford University Press, New York.

HENDERSON, A. 2000. Bactris (Palmae). Fl. Neotrop. Monogr. 79: 1-181.

HENDERSON, A., G. GALEANO AND R. BERNAL. 1995. A field guide to the palms of the Americas. Princeton University Press, Princeton, New Jersey.

Images

Arecaceae Bercht. & J.Presl appears in other Kew resources:

First published in Prir. Rostlin 266. 1820 [Jan-Apr 1820] ; nom. alt.: Palmae (1820)

Accepted by

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

Sources

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