N. Vietnam, prov. Cao Bang, distr. Tra Linh, municipality Co Muoi, vicinities of Lung Dat village (N 22ø51' E 106ø14'), about 22 km from Cao Bang town to the N. Primary mixed semideciduous forest (with Pseudotsuga brevifolia) along tops of limestone ridge at 900-1000 m alt. Epilite on open mossy rocks. Rare.
No CBL 1136 12 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)