Plants trees, shrubs, or climbers, sometimes armed; stems usually prominently ringed with leaf-scares, usually unbranched or dichotomously branched. Leaves usually with sheathing bases; petioles sometimes armed with spines (modified leaflets or epidermal emergences); blades pinnate, bipinnate, plamate, or costapalmate (with the periole extending into the blade as a well-defined cetral axis); leaflets induplicate or reduplicate, composed of 1 or more folds. Inflorescences axillary, usually single but occasionally grouped, often complex with bracteate branches of different orders, the ultimate branches with bracts subtending the flowers, the flowers solitary, paired, or in small groups. Flowers usually small, bisexual, unisexual or sterile males, usually 3-merous; tepals sometimes all similar, sometimed differentiated into calyces and corollas, free or united; stamens 3 to many, free ot united; anthers basi- or dorsifixed, straight or twisted, staminodes often present in female lfowers; carpels usually 1-3, free or united and forming a 3-celled ovaries; ovules solitary in each cell or carpedl; stigmas erect ir recurved, pistillodes often present in male flowers. Fruits usually 1-seeded, more rarely 210--seeded, usually with distinct epicarp (outer layer), mesocarp (middle layer) and endocarp (inner layer).
The Arecaceae, also known as Palmae, family includes about 200 genera and 2700 species which grow mostly in the tropics and subtropics, but relatively few in arid regions.