N. Vietnam, prov. Cao Bang, distr. Bao Lac, municipality Yen Lac, vicinities of Yen Lac village (N 22°44′ E 105°50′). Primary semideciduous broad-leaved forest on steep slopes and bluffs of N exposition of remnant karst limestone ridge at 1300-1350 elev. Terrestrial and lithophyte fern with fronds up to 0.4 m lg on steep shady slope. Not rare.
CBL 1363 13 April 1999
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)