N. Vietnam, prov. Cao Bang, distr. Ha Lang, municipality Thanh Nhat (N 22°41′ E 106°40′), about 42 km to E from Cao Bang town. Secondary open shrubs on alluvial foothills of remnant limestone ridges at 450-500 m alt. Woody vine up to 10 m lg. Flowers pale green.Not common.
CBL 706 27 Nov. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)