N. Vietnam, Prov. Cao Bang, Distr. Tra Linh, Subdistr. Quoc Toan, evergreen forest on slopes of remnant limestone mountains near Thang Heng lake in environs of Thang Hen and Lung Tao villages at 600-700 m alt.
Epilite. Flowers yellowish. Very common at 700-800 m alt.
VH 2464 04.01.1996
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 5094-93)
Participants: L. Averyanov, N.T. Ban, A. Budantzev, L. Budantzev, N.T. Hiep, D.D. Huyen, P.K. Loc, G. Yakovlev