Northern Vietnam, Lao Cai Prov., Van Ban Distr., Khanh Yen Ha municipality, in the vicinity of Na Nheo village (around point 22°00′08′'N, 104°17′43′'E). Old secondary open broad-leaved evergreen lowland forest with bamboo on very steep granite and quartzite slopes of mountain river canyon at elev. about 500 m a.s.l. Creeping epiphytic vine 6-10 m lg. Inflorescence white. Not rare.