N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′), about 44 km to NWW from Cao Bang town. Primary open coniferous and mixed mossy forest along tops of limestone remnant karst ridge at 1500 m alt. Epilite fern. Rare.
CBL 297 15 Nov. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)