Rhizome dorsiventrally flattened, 3-8 mm thick, short-creeping, internodes 5-10 mm long, not white waxy, roots sparsely set; vascular strands 8-14, with sclerified sheaths, sclerenchyma strands absent. Rhizome scales peltate or pseudopeltate, sparsely to densely set, appressed, (narrowly) ovate or triangular, 0.5-2 by 0.5-2 mm, margin entire or dentate, apex acute, often caducous, clathrate or subclathrate, sometimes with a hyaline margin, central region glabrous. Fronds not or slightly dimorphic, stipitate, herbaceous. Stipe 0.5-22 cm long, up to 4 mm thick; lamina pinnatifid, 45-70 by 25-60 cm, index 1.5-2; widest below, at, or above the middle, base truncate-angustate or narrowly angustate, decurrent on the stipe as a narrow wing, lobes 1-5 at each side, longest lobes at position 1-3 from base, 10-40 by 5-6 cm, widest about to above the middle, index 2.2-6, apex long-acuminate, margin entire; connected by a 0.1-2 cm wide wing, apical lobe longer than upper lateral lobes, widest below the middle, apex acuminate; lower surface with acicular hairs. Venation: veins prominent and distinct, 9-20 mm apart, ± straight, dichotomously branched near the margin, catadromous; connecting veins forming a row of large areoles bordered by several smaller areoles; included veins prominent and distinct, variously anastomosing within the main and marginal areoles, free veinlets simple to twice forked. Sori separate, round, 1-1.5 mm diam., superficial or slightly immersed, mostly irregularly scattered on the smallest veinlets, present in marginal and costal areoles, 10-15 per sq.cm, on the whole surface of the lamina; paraphyses simple uniseriate hairs with glandular topcells, 3-celled (or occasionally with a 1-celled subapical acicular branch).
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