N. Vietnam, prov. Cao Bang, distr. Tra Linh, municipality Quang Vinh (N 22°48′ E 106°17′), about 16 km from Cao Bang town to the N. Remnants of primary evergreen broadleaved forest on alluvial valley between remnant limestone ridges at 600 m alt. Terrestrial and epilite fern on steep slopes and crevices of vertical limestone remnant rocks. Very common.
CBL 1093 11 Dec. 1998
International Botanical Expedition of the U.S.A. National Geographic Society (grant No 6300-98)