N. Vietnam, prov. Cao Bang, distr. Ha Lang, municipality Thang Loi, vicinities of Lung Sam village (N 22°45′ E 106°42′). Not common weed up to 0.5 m hg in wet places along rice field at 550 m elev. Flowers yellow.
CBL 1702 24 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)