N. Vietnam, prov. Cao Bang, distr. Tra Linh, municipality Luu Ngoc, vicinities of Lung Mu village (N 22°47′ E 106°18′), about 14 km from Cao Bang town to the N. Secondary shrubs and grasslands on alluvial valley between remnant limestone ridges and mesas at 600-650 m alt. Prostrate herb along small streamlet in open place. Flowers white with pink tint. Common.
CBL 1171 13 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)