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. Open primary evergreen broadleaved closed forest on steep slopes and cliffs of limestone ridge at 500-600 m alt. Herb or shrublet up to 1.5 m hg on shadow rocks. Flowers white with violet tint toward the tips of tepals. Not common.
CBL 653 25 Nov. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)