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. Woody vine 15-20 hg. Flowers bright blue-violet, odorless. Not common.
CBL 1924 01 May 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)