N.Vietnam, Bac Kan Prov., Cho Don Distr., Ban Thi Municipality, Phia Khao village, Lung Li locality 22°17′30′'N 105°31′16′'E.
Primary broadleaved evergreen closed wet forest on very steep slopes and cliffs of remnant mountains composed with highly eroded crystalline limestone near top of ridge at elev. 900-1000 m a.s.l.
Lithophytic fern. Occasional.
HLF 774 25 Dec. 2002.
Coll. Phan Ke Loc, L.Averyanov, Nguyen Anh Duc, To Van Thao, Mai Van Xinh, Nguyen Tien Vinh. Grant from Henry Luce Foundation.