Rhizome terete, 1.6-3 mm thick, internodes 1.2-4.5 cm long or longer, not white waxy, roots sparsely set; vascular strands 15-25, without sclerified sheaths, sclerenchyma strands 15-50. Rhizome scales peltate, sparsely to densely set, appressed to slightly spreading, narrowly ovate or triangular, 3-6 by 0.5-2 mm, margin denticulate, sometimes only very slightly so, apex acute, clathrate or subclathrate, cells longitudinally rectangular, central region glabrous. Fronds not or slightly dimorphic, stipitate, membranaceous to thin-herbaceous. Stipe 6-55 cm long, 1.5-3 mm thick; lamina pinnatifid, broadly ovate to ovate, 18-70 by 13-45 cm, index 1-3, widest below to about the middle, base cuneate to cuneate-angustate, lobes 2-20 at each side, longest lobes at position 1-4 from base, connected by a wing 1-10 mm wide, widest below to about the middle, 10-20 by 0.8-2.3 cm, index 8-12, apex acute to long-acuminate; apical lobe longer than upper lateral lobes, 6-15 by 0.9-1.7 cm, widest about the middle; margin entire to undulate, lower surface without acicular hairs. Venation: veins slightly prominent and distinct, 4-8 mm apart, catadromous; connecting veins forming one row of small, inconspicuous, primary costal areoles, bordered by conspicuous large areoles; in fertile fronds the first connecting vein often forming, or contributing to, a distinct soral vein; included veins more or less immersed and indistinct or prominent and distinct, marginal vein absent, free veinlets simple to twice forked. Sori separate, round, superficial or slightly immersed, 1-3 mm diam., in 1 or 2 rows between midrib and margin, generally close to the costa, at most halfway to the margin, on the whole surface of the lamina or absent from the basal parts; paraphyses simple uniseriate hairs with glandular topcells.
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