N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′), about 44 km to NWW from Cao Bang town. Secondary open forest on alluvial foothills of remnant limestone ridge at 1100-1200 m alt. Terrestrial and epilite herb on wet shadow slopes along road. Not common.
CBL 286 15 Nov. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)