N. Vietnam, prov. Cao Bang, distr. Thach An, municipality Thuy Hung, vicinities of Na Lit village (N 22°30′ E 106°27′), about 27 km to SE from Cao Bang town. Secondary senideciduous open forest and shrubs along tops of remnant limestone ridge at 500-550 m alt. Epilite herb up to 0.6 m hg on open rocks. Very common.
CBL 906 04 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)