Vietnam, Quang Tri Prov., Huong Hoa Distr., Huong Viet Municipality, to N of Sa Mui pass, around point 16°51′14″N 106°34′13″E at elevation 550-650 m a.s.l.
Remnants of primary broad-leaved evergreen lowland forest on rocky remnant highly eroded solid marble-like limestone hills and low mountains with very steep slopes and vertical cliffs.
Terrestrial and lithophytic herb in shady wet places. Common.
HLF 5947 31 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.