N. Vietnam, Prov. Cao Bang, distr. Tra Linh, municipalite Quoc Toan, vicinity of Thang Heng and Lung Tao villages near Thang Heng lake. Broadleaved evergreen closed primary forest on steep slopes and bluffs on and near tops of limestone mesas and ridges at 700-1000 m alt. Terrestrial and epilitic herb on steep rocky slopes and on open rocks. Spathe white with green or yellow apical portion, boundary stripe between white and green part - brown. Not common. VH 4873 25-27.05.1997 International Botanical Expedition of the U.S.A. National Geographic Society (grant No 5803-96)