Trees or shrubs, dioecious or monoecious. Exudate absent*. Armed or not (spinescent, that is: branches sometimes ending in a sharp point). Indumentum present, hairs stinging. Stipules free*, simple, unlobed, entire *, not spine-like*, not leaf-like*, without glands. Leaves distributed evenly along stem or crowded towards shoot tip, alternate, simple, unlobed, base symmetrical, leaf margin usually entire, or almost so, less often toothed, leaf blade not pellucid-punctate, leaf glands absent; venation pinnate; domatia absent*; stipel-like structures absent*. Petiole present, without swellings or bends at base or apex*, without glands. Inflorescence with or without axis, male inflorescences axillary, racemose or fasciculate, short, sessile, few-flowered, female inflorescences axillary, terminal or lateral, raceme-like?, longer than the male, lax-flowered, at length pendulous, or flowers of both sexes on spinescent short shoots; bracts not leaf-like*, green. Male flowers: pedicels long, not articulated*; sepals 3–6, imbricate, partially fused, greenish; petals 0; disc 0; stamens (20)30–55, free, in several ros on a flat or concave receptacle; anther with conspicuous modification, apex with a tuft of small hairs, thecae extrorse in bud; pistillode absent. Female flowers: pedicel very short or absent; sepals 5–6, free, greenish; petals 0; disc 0; ovary locules 3, ovules per locule 1; styles 3, partially fused, style entire, styles or stigmas not flat*, surface papillose or plumose; staminodes absent. Fruit dehiscent, not sculptured, hairy, greenish to brown; seed without appendage, covering or membraneous layer*, not fleshy; embryo flat, not minute, cotyledons leaf-like.
An asterisk * indicates a state has been assumed but not yet confirmed.