N. Vietnam, Prov. Cao Bang, Distr. Tra Linh, Subdistr. Quoc Toan, evergreen forest on limestone mountains at 700-800 m alt. near Thang Heng lake in environs of Thang Hen and Lung Tao villages.
Epilite herb up to 0.4 m high in wet shadow places. Common at 700 m alt.
VH 2468 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