Plants scandent. Stem and branches sulcate-angular, glabrous or puberulent at nodes. Petiole slender, 3-8 cm, glabrous, eglandular; leaf blade ovate-cordate or broadly ovate-cordate, 6-13 × 4-11 cm, membranous, both surfaces puberulent at first, glabrescent, base cordate, sinus subquadrate, margin dentate, usually undivided or sometimes 3-5-lobed, apex acute or acuminate. Tendrils filiform, simple. Plants dioecious. Male flowers solitary in leaf axil; pedicel slender, 5-8(-14) cm, puberu-lent, apex bracteate; bract orbicular-reniform, 10-30 × 10-40 mm, both surfaces puberulent, glabrescent, base retuse, apex rounded to subacute; calyx segments ovate-oblong or lanceolate, 7-9 × 4-5 mm, pubescent, apex obtuse, retuse, broadly rounded, or acute; corolla yellow; segments oblong or obovate, 20-30 × 15-25 mm, 5-veined, apex obtuse-rounded; stamens 3 or 5; filaments filiform, ca. 3 mm, glabrous; anthers 2.5-3 mm; anther cells conduplicate. Female flowers solitary; pedicel filiform, 5-10 cm, usually with a minute bract at base; calyx and corolla as in male flowers; ovary ovoid-oblong or fusiform, 8-12 × 2-4 mm, ridged or verrucose, base attenuate. Fruiting pedicel slender, glabrous; fruit ovoid or ovoid-oblong, 3-7 × 2.5-4 cm, longitudinally sulcate or with rows of tubercles, both ends attenuate. Seeds gray or yellow-brown, oblong, ovoid, or globose, 7-14 × 5-8 mm, both surfaces slightly sculptured. Fl. Jun-Aug, fr. Aug-Nov.

Mountain slopes, thickets, roadsides; 800-2500 m. Guangdong, Guangxi, Guizhou, Yunnan [Bangladesh, India, Indonesia, Laos, Malaysia, Myanmar, Thailand, Vietnam].