N. Vietnam, prov. Cao Bang, distr. Nguyen Binh, municipality Ca Thanh (N 22°44′ E 105°50′). Primary evergreen broad-leaved forest on steep slopes and bluffs of remnant karst limestone ridge at 1300 m elev. Woody vine up to 3-4 m lg. Not common.
CBL 1310 13 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)