N. Vietnam, prov. Cao Bang, distr. Tra Linh, municipality Quang Vinh (N 22°48′ E 106°17′), about 16 km from Cao Bang town to the N. Secondary open broadleaved forest and shrubs on alluvial valley between remnant limestone ridges at 600-650 m alt. Terrestrial herb up to 1.5 m hg in open place. Flowers violet. Common weed all over the area.
CBL 1109 11 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)