Description from Flora of China
Lianas, sometimes rooting adventitiously, old stems sometimes developing prominent corky wings. Leaves opposite, long petiolate, usually 3-5-veined at base, sometimes strictly pinnately veined. Inflorescences umbel-like or producing a succession of cymules and eventually racemelike, sessile or pedunculate. Calyx glands 5. Corolla rotate to broadly campanulate [urceolate to globose]; lobes twisted to left or valvate. Corona lobes 5, stellate spreading or suberect, fleshy, adaxially often tuberculate, keeled or appendaged, apex entire, dentate, or lobed. Filaments connate into a tube, anther appendages short and obtuse; pollinia 2 per pollinarium, erect or subhorizontal, margin of inner angle raised and translucent. Stigma head dilated. Follicles linear or cylindric, usually paired, narrowly divergent to strongly reflexed, smooth. Seeds with coma.
About 30 species: China, India, Indonesia, Laos, Malaysia, Myanmar, Nepal, New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; Australia; nine species in China.
The occurrence of Heterostemma villosum Costantin in China has not been confirmed. Material so named seems better regarded as a hairy form of H. esquirolii.