Northern Vietnam, Lao Cai Prov., Van Ban Distr., to the west of Nam Xay village (around point 21°58′09′'N, 104°00′55′'E). Primary broad-leaved evergreen montane wet forest on granite and quartzite along stream canyon at elev. 1750-1800 m a.s.l. Climbing shrub up to 5-6 m hg. Flowers white. Not rare.