Son La Prov., Son La City, Chieng Co Municipality, around point 21°18′24”N 103°52′53”E.
Secondary evergreen dry open broad-leaved forest on very steep rocky slopes and on tops of remnant mountain composed with highly eroded marble-like solid crystalline limestone at elevation 800-900 m a.s.l.
Lithophytic fern in crevices of vertical shady cliff. Not rare.
CPC 1100 20 December 2010 Coll.: L.Averyanov, P.K.Loc, P.V.The, N.T.Vinh.