Description from Flora of China
Lianas woody, latex white. Leaves opposite. Cymes broadly paniculate, terminal or axillary, pedunculate. Flowers small. Calyx deeply divided, with many nectar glands inside. Corolla salverform or subcampanulate, tube short; throat broad, not scaly; lobes overlapping to left, spreading or reflexed. Stamens inserted at base of corolla tube; filaments short; anthers included, sagittate, connivent, adherent at middle to pistil head, cells with an empty tail; disc scales 5. Ovaries 2, free, longer than disc; ovules numerous in each locule. Style short; pistil head conical, apex obscurely 2-cleft. Follicles moniliform, with widely separated swellings, pendulous, elongated. Seeds fusiform, coma apical, early deciduous; endosperm scanty; cotyledons oblong, radicle short.
About four species: SE Asia, one species in China.