S. Vietnam, Prov. Lam Dong, distr. Lac Duong, municipalite Da Chay, 35 km to NE from Dalat city. Closed primary broadleaved evergreen mt forest on W macroslope of Gia Rinh mt. ridge at 1600-1650 m alt. (N 12° 09′, E 108° 41′). Woody vine up to 15 m lg with milky juice. Flowers white. Not common. VH 4549 04.05.1997 International Botanical Expedition of the U.S.A. National Geographic Society (grant No 5803-96)
Collectors: L. Averyanov, N.Q. Binh, N.T. Hiep, P.K. Loc, P. Lowry