Vietnam, Quang Tri Prov., Huong Hoa Distr., Huong Phung Municipality, Sa Mui pass, around point 16°48′36″N 106°34′44″E at elevation about 1300-1500 m a.s.l.
Primary broad-leaved evergreen submontane forest on very steep rocky shale southern slopes of Sa Mui Mountain.
Woody vine up to 30 m long on shady slope. Not rare.
HLF 5822 29 March 2006. Photo.
Coll. N.T.Hiep, L.Averyanov, P.K.Loc, P.V.The, N.S.Khang, P.H.Duc, L.T.Son, S.Bounphanmy, T.K.Ratana, O.Sonliya, T.Q.Dang, N.V.Hien, H.T.N.Trang, L.T.Chau. Grant from Henry Luce Foundation.