N. Vietnam, prov. Cao Bang, distr. Ha Lang, municipality Dong Loan, vicinities of Ban Lung and Lung Phuc (N 22°46′ E 106°44′), about 50 km to E from Cao Bang town. Secondary evergreen forest on alluvial walley among limestone rocks on foothills of remnant limestone ridges at 400 m alt. Prostrate herb in open wet places, flowers white with rose tips of petals. Very common. Commonest weed in the area.
CBL 579 24 Nov. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)