N. Vietnam, prov. Cao Bang, distr. Tra Linh, municipality Luu Ngoc, vicinities of Lung Mu village (N 22°47′ E 106°18′), about 14 km from Cao Bang town to the N. Primary coniferous and mixed semideciduous open forest (with Pseudotsuga brevifolia) along tops of limestone ridge at 800 m alt. Epilite herb on steep shadow slopes and vertical cliffs. Common.
CBL 1211 13 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)
Collectors: N.T.Hiep, N.Q.Binh, P.K.Loc, N.X.Tam, Averyanov L.