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.
Terrestrial herb up to 1 m tall along rocky ridge edge. Occasional.
HLF 5818 29 March 2006.
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.