Ha Giang prov., Quan Ba distr., Bat Dai Son Nature Reserve, Can Ty commune, Lung Vay village, around point 23°05ʹ46.7ʺN 105°02ʹ53.1ʺE, 1100-1280 m a.s.l., karstic, highly eroded mountains composed of solid marble-like limestone, primary evergreen broad-leaved humid forest on steep rocky slopes near mountain tops. Creeping epiphytic vine 3-4 m long (or more) in shady place, inflorescences white to light yellowish. Not common. 15 April 2018, L. Averyanov, Nguyen Sinh Khang, Chuong Quang Ngan, T. Maisak, VR 184 (HN, LE01054463, LE01054464).