N. Vietnam, prov. Cao Bang, distr. Ha Lang, municipality Thang Loi, vicinities of Ban Hao (N 22°43′ E 106°40′), about 43 km to E from Cao Bang town. Secondary evergreen broadleaved closed forest on steep bluffs of remnant limestone ridges at 350-400 m alt. Epilite herb on vertical shadow cliffs of NW exposition. Leaves below purple-violet. Rare.
CBL 695 26 Nov. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)