N. Vietnam, prov. Ha Giang, distr. Yen Minh, municipality Lao Va Chai, vicinities of Ngan Chai village, 6 km to W of Yen Minh town (N 23°07′ E 105°08′). Primary evergreen wet mossy mixed forest (with domination of Tsuga chinensis and Pinus kwangtungensis) along tops of karst remnant limestone ridge at 1500-1600 m elev. Terrestrial herb up to 0.5 m hg on very steep mossy wet rocky slope. Flowers white with light violet tint. Not common, but occasionally abundant.
CBL 1903 01 May 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)