Trees or shrubs. Branches or branchlets ± stellate. Leaves simple, entire or serrate. Flowers bisexual, solitary or cymose, axillary or rarely terminate. Epicalyx lobes minute. Calyx tube-shaped, 5-lobed, lobes usually unequal and 2-lipped. Petals 5, equal to each other or 2-lipped, clawed and usually with auriculate appendage. Anthers 10, on top of elongate androgynophore; filaments ± connate, enclosing pistil; staminodes 5, within stamens. Ovary 5-celled, 5-angular; ovules numerous in each locule; styles 5, linear, apically slightly swollen. Mature capsule straight or spirally twisted, usually densely hairy, often with soft setae which are themselves hairy. Seeds verrucose.

About 60 species: tropical America and Asia; ten species (one endemic) in China.