Rhizome dorsiventrally flattened, 1.5-4 mm wide, short-creeping, internodes 5-35 mm long, not white waxy, roots sparsely set; vascular strands 9-10, with sclerified sheaths, sclerenchyma strands absent. Rhizome scales pseudopeltate, densely set, distinctly spreading, ovate, narrowly ovate or triangular, 2-5 by 0.5-1.5 mm, margin denticulate, apex acute, clathrate or subclathrate, central region glabrous or bearing multiseptate hairs when young. Fronds not or slightly dimorphic, stipitate, herbaceous. Stipe 2-15 cm long, 0.5-1.5 mm thick; lamina simple or irregularly lobed, narrowly elliptic or ovate to linear, 10-30 by 1.5-3 cm (excluding the narrowly triangular lobes), index 6.5-15, base narrowly angustate, decurrent into a long wing, lobes, if present, up to 9 by 1 cm; margin sinuate, apex acute to acuminate, lower surface without acicular hairs. Venation: veins more or less immersed and indistinct, 5-12 mm apart, zigzag, dichotomously branched near the margin; connecting veins 2-4, catadromous, forming equally sized, sometimes irregularly shaped, areoles, sometimes also a row of small primary costal areoles; included veins more or less immersed and indistinct, variously anastomosing, free veinlets simple or once forked. Sori separate, round or elongate along the veinlets, superficial or slightly immersed, 1-2 by 2.5-4 mm, mostly irregularly scattered on the smallest veinlets, sometimes forming 2 irregular rows between the veins, 5-20 per sq.cm, on the whole surface of the lamina or absent from the basal parts for 0.5 of total length of lamina, present or absent in marginal areoles, generally present in costal areoles; paraphyses simple uniseriate hairs with glandular topcells, 2-4-celled.
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