Northern Vietnam, Lao Cai Prov., Van Ban Distr., to the west of Nam Xay village (21°58′42′'N, 104°00′37′'E). Primary evergreen wet broad-leaved montane forest at elev. 1600-1700 m a.s.l. Lithophytic herb on mossy open granite wet boulders along stream. Flowers light violet-blue. Rare.