Davallia membranulosa Wallich ex Hooker, 1845
Description
Rhizome without the scales 2-4 mm in diametre (D. membranulosa Rhizome). Scales brown, red-brown, or nearly black, with pale border from base to apex, narrowed evenly towards the apex, not bearing multiseptate hairs, lacking marginal setae or teeth or those rare, peltate, 5-6 mm long. Stipes pale, adaxially grooved, 3-15 cm long, bearing hairs and or scales when young. Lamina compound (D. membranulosa Habitus), bipinnate towards base and in the middle part, elongate, not or hardly narrowed towards base, bearing multicellular hairs, 12-27 cm long by 5-14 cm broad, not or slightly dimorphous. Longest petiolules 0.5-1.5 mm long. Pinnae linear-triangular. Longest pinnae 2.6-7 cm long by 1-3 cm broad. Pinnules of at least the larger pinnae catadromous or anadromous (but often opposite), linear oblong (pinnatipartite, the lobes entire or shallowly lobed). Longest pinnules 6-15 mm long by 2-4 mm broad. Leaf axes, at least rachises, hairy. Hairs 0.4-0.6 mm long. Veins in sterile ultimate lobes simple or forked, not reaching the margin. False veins not present. Sori separate, frequently single on a segment at the forking point of veins or (rarely) at the bending point of a vein. Indusium attached at the broad base and hardly or not at the sides, semicircular or oblong (to circular), longer than wide to wider than long, 0.5-0.8 mm long by 0.5-0.8 mm broad (D. membranulosa SEM1, picture of indusia).
Distribution
Continental Asia: India (Darjeeling 1 coll., Kumaon 3 coll., Saharanpur 1 coll.); Nepal (2 coll.); Sikkim (1 coll.); Burma (Kengtung state 1 coll.); Northern Thailand (Chieng Mai, Chieng Rai, Tak, 17 coll.); Vietnam (Tonkin, Chapa 1 coll.); China (Yunnan 8 coll., Sichuan 1 coll.).
Ecology
Epilithic or epiphytic in forest. Altitude 600-2600 m.
Spores
Surprisingly, two kinds of spores are found in this species. Feng 13127 has coarse verrucae coherent in parallel rows at the distal face, while Maxwell 88-847 shows finely colliculate verrucae. This difference is not matched, however, with morphological traits.