N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′). Primary mixed semideciduous forest (with domination Keteleeria chinensis) along tops of remnant karst limestone ridge at 1450-1500 m elev. Terrestrial and lithophyte herb in shady places. Flowers light blue-violet. Common.
CBL 1472 16 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)