FLORA OF VIETNAM Polypodiaceae s.l. Asplenium unilaterale
Vietnam, Ha Giang Prov., Hoang Su Phi Distr., Ho Thau Municipality, around Chien Thang village, about 4 km to NW of Ho Thau village (22°37′24″N, 104°38′00″E) at elev. 1200-1500 m a.s.l.
Remnants of heavily logged primary and secondary closed evergreen broad-leaved forest on very steep slopes of mountains composed with shale and granite with quartzite.
Lithophytic and epiphytic fern in shady rocky stream canyon. Very common.