N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′). Secondary open broadleaved forest on alluvial foothills of remnant karst limestone ridges at 1050-1100 m elev. Terrestrial herb in wet open places. Flowers blue. Common. Usual weed in the area.
CBL 1357 14 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)