N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′). Secondary open broadleaved forest on alluvial foothills of remnant karst limestone ridges at 1050-1100 m elev. Woody vine 3-4 m lg on open rocks. Flowers white. Not common.
CBL 1350 14 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)