S.Vietnam, Thua Thien Hue Prov., Phu Loc Distr., Bach Ma National Park, primary mixed and broad-leaved evergreen forest on N slopes of Bach Ma range around point 16°11′10′'N 107°50′18′'E at elev. 1100-1200 m a.s.l.
Woody vine 6-8 m long with milky juice. Flowers white. Occasional.
HLF 1345 26 April 2003.
Coll. N.T.Hiep, L.Averyanov, N.T.Vinh et al. Grant from Henry Luce Foundation.