Description from Flora of China
Herbs twining. Stems terete, 0.25-2 m, pubescent when young, glabrescent. Petiole 1-6 cm, pubescent; leaf blade lanceolate, ovate or ovate-oblong, 1.5-8 X 0.5-5 cm, ± villous or glabrous adaxially, base cordate or rounded to cuneate, apex acuminate, mucronulate; lateral veins 5-8 pairs. Inflorescences umbelliform-cymose, loose to dense; peduncle 0.3-4 cm; bracts subulate. Pedicel 3-5 mm, pubescent. Sepals unequal, ± acuminate apically, pilose to glabrous abaxially; outer 3 ovate to ovate-lanceolate, 5-7 X ca. 4 mm; inner 2 smaller. Corolla lilac, pale purple, pink, or white, funnelform, 0.8-1.2 cm; limb shallowly 5-lobed, glabrous or lobes sparsely pubescent apically. Filaments subequal, pubescent basally; anthers oblong. Ovary glabrous. Style ca. 8 mm; stigmas oblong. Capsule globose, 3-4 mm in diam., 8-valved. Seeds brownish yellow to purplish black, 1.5-2 mm, minutely tuberculate, glabrous, edges narrowly winged. 2n = 18.
Thickets, grassy areas, forest clearings, roadsides, often on dry soils; 0-600 m. Guangdong, Guangxi, Hainan, Taiwan, Yunnan [Cambodia, India, Indonesia, Laos, Malaysia, Myanmar, New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; Africa, Australia, Pacific Islands]