Description from Flora of China
Shrubs or trees. Leaves alternate; stipules absent. Flowers small, 2 to many fascicled and axillary, pedicellate or sessile. Sepals 5(or 6), usually glabrous or inside tomentose. Corolla tube campanulate, usually extended, (4- or)5--11-lobed. Stamens (4 or)5--10 in 1 whorl, inserted in throat and opposite corolla lobes; staminodes absent. Ovary 1--10-locular, villous or glabrous. Style longer to shorter than ovary. Fruit 1--8-seeded, exocarp thick to very thin. Seed coat papery to crusty; scar narrow to wide, lateral, sometimes almost covering entire seed.
About 70 species: Madagascar; tropical and subtropical America, tropical Africa and Asia; one species in China.