N. Vietnam, prov. Ha Giang, distr. Dong Van, municipality Ho Quang Phin, vicinities of Ta Xa village, 14-16 km to SSW of Dong Van town (N 23°16′ E 105°22′). Primary very wet mossy cloud mixed forest (with domination of Tsuga chinensis and Pinus kwangtungensis) along tops of karst remnant limestone ridge at 1550-1600 m elev. Lithophyte herb on vertical cliffs. Leaves above deep green with white venation, deep purple-violet below. Flowers deep blue-violet. Very common.
CBL 1764 28 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)