Description from Flora of China
Convolvulus gemellus N. L. Burman, Fl. Indica 46, t. 21. 1768; Ipomoea gemella (N. L. Burman) Roth; I. polyantha Miquel.
Herbs, twining or prostrate; axial parts smooth, appressed yellowish pubescent. Stems often rooting at nodes and internodes. Petiole 1.5-6 cm, rarely minutely tuberculate; leaf blade often ovate, 2.5-6.5 X 1.5-4.3 cm, glabrous or short pilose, base broadly cordate, proximal margin entire, undulate or coarsely crenate, sometimes 3-lobed, apex ± attenuate, mucronulate. Inflorescences umbelliform or forked with short racemelike branches, few flowered; peduncle 2.5-10 cm; bracts early deciduous, minute. Pedicel 3-6 mm. Sepals broadly obovate to ± circular, ± unequal, margin scarious, emarginate, slightly mucronulate or not, slightly enlarged in fruit; outer 2 abaxially ± pilose, 4-6 mm; inner 3 subglabrous, 6-7 mm. Corolla yellow, campanulate to funnelform, 1.5-2 cm, midpetaline bands dark, glabrous outside; limb shallowly 5-lobed; lobes emarginate and mucronulate. Filaments pubescent basally. Ovary glabrous. Capsule depressed-globose, ca. 7 mm, coarsely wrinkled. Seeds trigonous, dark gray or brownish puberulent. 2n = 58.
Thickets, roadsides, waste places; 0-200 m. Taiwan [?Cambodia, Indonesia, ?Laos, Malaysia, ?Myanmar, New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; Australia].