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.
Herb up to 1.5 m high. Common at 600-700 m alt.
VH 2461 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