Arecaceae Bercht. & J.Presl

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

Morphology 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

Morphology General 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

Morphology Reproductive morphology 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)

Morphology Reproductive morphology 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

Morphology Reproductive morphology 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

Morphology Reproductive morphology 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

Morphology Reproductive morphology Seeds Germination

Germination remote-tubular, remote-ligular or adjacent-ligular; seedling leaves simple or compound

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

Morphology General 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

Morphology 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

Morphology Reproductive morphology Flowers

Flowers small, actinomorphic, bisexual, monoecious or dioecious, sometimes polygamous, arranged in an often paniculate inflorescence (spadix) either amongst or below the leaves

Morphology Reproductive morphology 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

Morphology Reproductive morphology Flowers Perianth

Perianth double

Morphology Reproductive morphology Flowers Calyx

Sepals 3, separate or connate, imbricate or open in bud

Morphology Reproductive morphology Flowers Corolla

Petals 3, separate or connate, usually valvate in the male flowers and imbricate in the female

Morphology Reproductive morphology Flowers 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

Morphology Reproductive morphology Flowers 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

Morphology Reproductive morphology Fruits

Fruit a berry or drupe, 1-2-locular, or fruiting carpels distinct; exocarp often fibrous, sometimes covered by reflexed scales

Morphology Reproductive morphology Seeds

Seeds free or adherent to the endocarp; endosperm present, sometimes ruminate; embryo small

Gemma Bramley, Anna Trias-Blasi & Richard Wilford (2023). The Kew Temperate Plant Families Identification Handbook. Kew Publishing Royal Botanic Gardens, Kew

Recognition

Characters of similar families: Pandanaceae: linear leaves, flowers complex and not usually trimerous, fruit in heads. Cyclanthaceae: leaves not developing from an initially entire lamina. Asparagaceae (for example, arborescent Yucca, Cordyline, Dasylirion and Dracaena): linear leaves, not compound or plicate. Musaceae: non-woody pseudostems arising from corms, leaf entire. Cycadaceae: cone-bearing, compound leaves not developing from an initially entire lamina.

Morphology General Habit

Massive to minute woody monocotyledonous plants; trees, shrubs or climbers, sometimes spiny

Morphology Stem

Stems clustered or solitary, erect, creeping or climbing, often massive, sometimes very short and/or subterranean, usually marked with leaf scars, sometimes dying after flowering, aerial stems usually unbranched

Morphology Leaves Leaf lamina

Lamina almost always conspicuously folded

Morphology Leaves

Leaf bases always tubular and sheathing (at least in the bud), often forming a conspicuous tubular crownshaft Leaves compound, less frequently entire; compound leaves derived by splitting of an initially entire lamina, pinnate, bipinnate or palmate

Morphology Reproductive morphology Inflorescences

Inflorescences always lateral, often massive, spicate to paniculate, sometimes aggregated in a mass of inflorescences held above the leaves, resulting in the death of the stem

Morphology Reproductive morphology Flowers

Flowers bisexual or unisexual (monoecious or dioecious); calyx or corolla usually comprising 3 free or fused sepals or petals, often inconspicuous, but some colourful and enlarged; ovary always superior, always no more than one ovule per carpel

Morphology Reproductive morphology Fruits

Fruit a berry or drupe; minute to massive, usually 1–3-seeded, often brightly coloured, sometimes scaly or spiny.

Distribution

181 genera, c. 2,600 species. Primarily tropical and subtropical, especially in humid forests, but reaching temperate climates at their northern (southern France) and southern (Chatham Islands) limits. Also reaching high elevations in the tropics (up to 3,600 m in the Andes).

Note

Woody monocot trees, shrubs or climbers. Leaves usually compound, palmate, pinnate or rarely bipinnate, blade plicate, splitting along folds. Leaf bases tubular, usually sheathing. Inflorescences lateral. Fruit a berry or drupe.

Description Author

William J. Baker

Timothy Utteridge & Gemma Bramley (2020). The Kew Tropical Plant Families Identification Handbook, Second Edition. Kew Publishing Royal Botanic Gardens, Kew

Note

Woody monocot trees, shrubs or climbers. Leaves usually compound, palmate, pinnate or rarely bipinnate, blade plicate, splitting along folds; leaf bases tubular, usually sheathing. Inflorescences lateral. Fruit a berry or drupe.

Recognition

Characters of similar families: Pandanaceae: linear leaves, flowers complex and not usually trimerous, fruit in heads. Cyclanthaceae: compound leaves not developing from an initially entire lamina. Asparagaceae (e.g. arborescent Yucca, Dasylirion and Dracaena): linear leaves, not compound or plicate. Musaceae: non-woody pseudostems arising from corms, leaf entire. Cycads: cone-bearing, compound leaves not developing from an initially entire lamina.

Morphology General Habit

Massive to minute woody monocotyledonous plants; trees, shrubs or climbers, sometimes spiny

Morphology Stem

Stems clustered or solitary, erect, creeping or climbing, often massive, sometimes very short and/or subterranean usually marked with leaf scars, sometimes dying after flowering, aerial stems usually unbranched

Morphology Leaves

Leaf bases always tubular and sheathing (at least in the bud), often forming conspicuous tubular crownshaft Lamina almost always conspicuously folded Leaves compound, less frequently entire; compound leaves derived by splitting of an initially entire lamina, pinnate, bipinnate or palmate

Morphology Reproductive morphology Inflorescences

Inflorescences always lateral, often massive, spicate to paniculate, sometimes aggregated in a mass of inflorescences held above the leaves resulting in the death of the stem

Morphology Reproductive morphology Flowers

Flowers bisexual or unisexual (monoecious or dioecious); calyx/corolla usually comprising 3 free or fused sepals/petals, often inconspicuous, but some colourful and enlarged; ovary always superior, always no more than one ovule per carpel

Morphology Reproductive morphology Fruits

Fruit a berry or drupe; minute to massive, usually 1–3-seeded, often brightly coloured, sometimes scaly or spiny.

Distribution

181 genera, c. 2,600 species. Pantropical and subtropical, mainly in tropical America, South- East Asia and Malesia.

Ecology

Most species are found in humid forest.

Description Author

William J. Baker

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

Morphology General Habit

Massive to minute woody monocotyledonous plants; trees, shrubs or climbers, sometimes fiercely spiny

Morphology Stem

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

Morphology Leaves Leaf lamina

Lamina almost always conspicuously folded

Morphology Leaves

Leaf bases always tubular and sheathing (at least in the bud), often forming conspicuous tubular crownshaft Leaves compound, less frequently entire; compound leaves derived by splitting of an initially entire lamina, pinnate, bipinnate or palmate

Morphology Reproductive morphology Inflorescences

Inflorescences always lateral, often massive, spicate to paniculate, sometimes aggregated in a mass of inflorescences held above leaves resulting in death of  stem

Morphology Reproductive morphology Flowers

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

Morphology Reproductive morphology Fruits

Fruit berry or drupe; minute to massive, usually 1-3 seeded, often brightly coloured, sometimes scaly or spiny .

Distribution

Widespread in Neotropics, especially in rainforest. For generic distributions see www.palmweb.org or literature below. Native. Cultivated. Naturalised. Many genera endemic.

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. 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 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. 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. Often spiny.

Note

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. 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

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution

The family has c. 2600 species in 187 genera. Pantropical and subtropical, mainly tropical America, Asia and Pacific regions.

Ecology

Most species are found in humid forest.

Note

Currently 34 genera recorded from New Guinea, three of which are rattans - Calamus L. (including Daemonorops Blume ex Schult.f.) and Korthalsia Blume. The remainder are treated here.

Morphology General Habit

Massive to small woody monocotyledonous plants; trees, shrubs or climbers, sometimes spiny

Morphology Stem

Single- or multiple-stemmed, stems erect, creeping or climbing, often massive, sometimes very short and/or subterranean, usually marked with leaf scars, sometimes dying after flowering, aerial stems usually unbranched

Morphology Leaves Leaf lamina

Lamina almost always conspicuously folded

Morphology Leaves

Leaf bases always tubular and sheathing (at least in the bud), often forming conspicuous tubular crownshaft (in pinnate-leaved tree palms only). Inflorescences always lateral, often massive, unbranched to paniculate, sometimes aggregated in a mass of inflorescences held above the leaves resulting in the death of the stem Leaves compound, less frequently entire; compound leaves derived by splitting of an initially entire lamina, pinnate, bipinnate or palmate

Morphology Reproductive morphology Flowers

Flowers bisexual or unisexual (monoecious, dioecious, rarely polygamous); calyx/corolla usually comprising 3 free or fused sepals/petals, often inconspicuous, but some colourful and enlarged; ovary always superior, always no more than 1 ovule per carpel

Morphology Reproductive morphology Fruits

Fruit a berry or drupe; minute to massive, usually 1–3 seeded, often brightly coloured, sometimes scaly or spiny

Use

Numerous uses as a source of food and fuel and in construction, handicrafts, clothing, horticulture and spiritual traditions.

Use

Numerous uses for food sources, construction, handicrafts, clothing, fuels, horticulture, spiritual uses.