N. Vietnam, prov. Lao Cai, distr. Sa Pa, near Tram Tau village, N slope of Hoang Lien Son ridge at 1950-2000 m elev. (N 22°20′ E 103°50′). Secondary broadleaved evergreen wet forest with remnants of primary elements on shales. Woody vine 8-12 m lg along streamlet. Flowers yellow. Not common.
NTH 2657 18 May 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)