Rhizome 4-8 mm thick, not glaucous, brownish when dry, shortly creeping, phyllopods raised, 1.5-2 cm distant. Anatomy: vascular strands c. 12, without sclerified bundle sheaths, sclerenchyma strands absent, ground tissue not sclerified or with some erratic sclerification. Rhizome scales pseudopeltate, appressed, 6.5-8 by 2 mm, clathrate, margin regularly dentate, apex acute. Fronds not or very shortly stipitate, stipe to c. 0.7 cm; lamina to 150 by 1.5-3.3 cm, papyraceous, strap-shaped or widest at 1/3-1/2 its length, at base very gradually narrowed to a short truncate base, apex rounded to acute, margin flat or very slightly incurved; costa sparsely set with dark clathrate, dentate, elongate scales, similar but smaller scales sparsely scattered over the lower surface of the lamina. Venation usually quite visible, main veins indistinct, all veins forming a mesh of areoles. Free veinlets many, recurrent and excurrent. Hydathodes present, superficial. Sori round or slightly elongated transversely, to 6 by 4 mm, impressed, densely covered with scales when young, in a single row close to or up to 2 mm from the costa. Sporangia long-stalked, capsules c. 0.4 mm long, with 14 or 15 indurated annulus cells. Soral scales of two types: dark, peltate, round, irregularly dentate clathrate scales to 0.5 mm diam., deciduous or remaining as a dark ring around the ripe sorus; and brown, irregularly branched scale-like hairs remaining between the old sporangia. Spores hyaline, c. 70 by 50 µm, coarsely verrucate.
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