N. Vietnam, prov. Cao Bang, distr. Tra Linh, municipality Quang Vinh (N 22°51′ E 106°14′), about 21 km from Cao Bang town to the N. Primary evergreen closed wet forest on steep slopes and bluffs of remnant limestone ridge at 650-800 m alt. Terrestrial and epilite herb up to 40 cm hg in shadow places. Leaves below violet. Common.
CBL 979 09 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)