Rhizome 3-4.5 mm thick, often slightly glaucous, ascending to short-creeping, phyllopods raised, contiguous or very short-spaced. Anatomy: vascular strands to 18, without sclerified bundle sheaths, sclerenchyma strands many, scattered, smaller towards the periphery, ground tissue not sclerified. Rhizome scales appressed, 3.5-4 by 1 mm, clathrate, often somewhat parenchymatous near the attachment, superficially set with long unicellular hairs, margin irregularly coarsely dentate, apex acute. Fronds stipitate; stipe to 8 cm long, not distinctly delimitated from the narrowed lamina base, lamina to 70 by 1-4.5 cm, chartaceous, glabrous, strap-shaped or widest at 1/3-1/2 its length, base very gradually narrowed into the stipe, rounded to acute, margin often incurved. Venation: veins immersed in the lamina, main veins indistinct, all veins forming a mesh of areoles. Free veinlets many, recurrent and excurrent. Hydathodes absent. Sori round or elongated longitudinally, to 10 by 2 mm, sunken, densely covered with scales when young, in a single row at 1-2 mm from the margin, margin often incurved over the sori. Sporangia long-stalked, capsules c. 0.3 mm long, with 13 or 14 indurated annulus cells. Soral scales of two types: dark, peltate, round, entire, clathrate scales to 0.3 mm diam., deciduous or remaining as a dark ring around the ripe sorus; and brown, irregularly shaped, mostly basifixed scales with irregularly thickened cell walls, remaining between the old sporangia. Spores hyaline, c. 50-60 by 35 µm, verrucate.
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