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 evergreen forest on steep slopes and bluffs of limestone
remnant karst ridge at 1100 m elev. Woody vine 10-15 m lg. Flowers white. Not common.
CBL 1429 16 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)