Davallia membranulosa Wallich ex Hooker, Sp. Fil. 1: 159. 1845; Acrophorus membranulosus (Wallich ex Hooker) T. Moore; Araiostegia membranulosa (Wallich ex Hooker) Holttum; Davallodes membranulosa (Wallich ex Hooker) Copeland; Humata membranulosa (Wallich ex Hooker) Diels; Leucostegia membranulosa (Wallich ex Hooker) J. Smith.

Rhizome 2-4 mm in diam., densely covered with scales. Scales brown, red-brown, or nearly black, with pale border from base to apex, narrowed evenly toward apex, peltate, 5-6 mm, without multiseptate hairs, lacking marginal setae or teeth or those rare. Fronds 1.5-3 cm apart; stipe pale, adaxially grooved, 3-15 cm, 1.5-2 mm in diam., with hairs and/or scales when young; lamina compound, bipinnate toward base and in middle part, elongate, not or hardly narrowed toward base, 12-27 × 5-14 cm, with multicellular hairs, not or slightly dimorphic. Longest petiolules 0.5-1.5 mm; pinnae linear-triangular; longest pinnae 2.6-7 × 1-3 cm; pinnules of at least larger pinnae catadromous or anadromous (but often opposite), linear-oblong (pinnatipartite, lobes entire or shallowly lobed); longest pinnules 6-15 × 2-4 mm. Rachises and costae, at least rachises, hairy; hairs 0.4-0.6 mm. Veins in sterile ultimate lobes simple or forked, not reaching margin; false veins not present. Sori separate, frequently single on a segment, at forking point of veins or (rarely) at bending point of a vein; indusium attached at broad base and hardly or not at sides, semicircular or oblong (to circular), longer than wide to wider than long, 0.5-0.8 × 0.5-0.8 mm.

One of us (Nooteboom) considers that although Ching (Acta Phytotax. Sin. 11: 20. 1966) recognized two species, Paradavallodes chingiae and P. membranulosa, careful examination of the types leads to the conclusion that there is only one, easily recognizable species, i.e., P. membranulosa. However, two of us (Xing and Wang) do not support P. chingiae as a synonym of P. membranulosa on account of differences in the leaf texture and pubescence. In addition, according to scanning electron microscope observations, the spore ornamentation of P. chingiae is lophate, whereas that of P. membranulosa is verrucate.

Epilithic or epiphytic in forests; 600-2600 m. Sichuan, Yunnan [Bhutan, India, Myanmar, Nepal, N Thailand, Vietnam].