N. Vietnam, prov. Cao Bang, distr. Ha Lang, municipality Thang Loi, vicinities of Lung Sam village (N 22°45′ E 106°42′). Secondary open shrubs and grasslands on alluvial shale valley between limestone karst remnant ridges at 500 m elev. Shrub 1-1.5 m hg. Flowers purple-violet.
Rare.
CBL 1669 24 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)