Northern Vietnam, Tuyen Quang Prov., Chiem Hoa Distr., Binh An Municipality, in the vicinity of point 22°25′38′'N, 105°10′00′'E. Secondary evergreen seasonal broad-leaved forest with bamboo on highly eroded remnant ridge composed with soft stratified limestone and lime schist consolidated with numerous quartzite dikes at elev. 450-550 m a.s.l. Terrestrial and lithophytic fern on shady rocky very steep slope. Locally very common, usual co-dominante of lithophytic herb communities.