Description from Flora of China
Woody climbers, evergreen. Monoecious or dioecious. Winter bud scales many, in several whorls; outer scales imbricate, usually short and broad; inner scales longer than outer ones, ligulate to straplike. Leaves alternate, long petiolate; leaf blade palmately 3--9-foliolate or pinnately 3-foliolate; petiolules unequal; leaflet margins entire. Inflorescences axillary, several to more than 10-flowered; bracts subtending inflorescences, scaly. Sepals 6, outer 3 valvate. Petals absent or 6 and inconspicuous. Male flowers: stamens 6; filaments connate into a tube, basally, or only at base; connective apical appendage often hornlike or apiculate. Pistillodes 3, concealed within filaments tube. Female flowers: sepals usually slightly larger than those of male flowers. Staminodes minute, squamose, sessile, inserted at base of carpels opposite petals. Carpels 3, straight, sessile; ovules in several rows. Stigma terminal. Fruit single or in pairs, rarely 3-fascicled, sometimes dehiscent along abaxial suture. Seeds numerous, embedded in pulp.
About 25 species: China, N India, Japan, Myanmar, Vietnam; 20 species (16 endemic) in China.