N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′). Secondary wet short tall grasslands on alluvial shale valley between limestone remnant karst ridges at 1000-1050 m elev. Herb 20-25 cm hg. Flowers white. Common.
CBL 1326 14 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)