Herbs or subshrubs, annual or perennial, usually erect, stellate hairy or sometimes glabrate, sometimes with long simple hairs. Leaves simple; leaf blade ovate to narrowly triangular, without foliar nectaries, base cordate, margin entire or crenate-dentate, apex acuminate. Flowers axillary or subterminal, usually grouped into terminal panicles. Pedicels articulate. Epicalyx absent. Calyx shallowly cup-shaped to campanulate, lobes 5, longer than tube. Corolla yellow, cream, or white, small, ± rotate; petals 5, connate at base, adnate to filament tube. Filament tube shorter than free portions of filaments; anthers all terminal, not exserted. Ovary 3-5-loculed; ovules 3 per locule, usually erect; style arms as many as locules, filiform, longer than filaments; stigmas capitate. Fruit a schizocarp but septicidal dehiscence often incomplete (i.e., pseudocapsular), obconical; mericarps 3-5, eventually dehiscent, transversely divided by an internal septum into an indehiscent proximal cell and a dehiscent terminal cell, apex beaked. Seeds 1-3 per mericarp, 1 in proximal cell and usually 2 in distal cell, pubescent (seed in proximal cell more densely so).

Between 25 to 30 species: mainly in tropical America with a few in tropical Asia and Africa; one species in China.