Rhizome terete, 1-2 mm thick, internodes (0.2-)1-8 cm, not white waxy, roots sparsely set; vascular strands 10-13, with or without sclerified sheaths, sclerenchyma strands 10-20. Rhizome scales peltate, densely set, appressed, round or elliptic, 0.8-1.2 by 0.5-1 mm, centrally dark, clathrate, margin hyaline, entire, irregular, often eroded, apex rounded, cells small, more or less isodiametric, central region glabrous. Fronds not or slightly dimorphic, stipitate, herbaceous or subcoriaceous. Stipe 2.5-15 cm long, 1 mm thick; lamina simple, elliptic, 10-18 by 1.7-5 cm, index 2.5-5, base cuneate-angustate, margin entire, apex acute to caudate, lower surface without acicular hairs. Venation: veins more or less immersed and indistinct, 6-10 mm apart, more or less straight, dichotomously branched near the margin; connecting veins 2 or 3, not clearly distinct, anadromous or catadromous; in fertile fronds the first connecting vein often forming, or contributing to a distinct soral vein; included veins more or less immersed and indistinct, with the connecting veins forming a net of areoles, but not within the costal areole, free veinlets simple to twice forked. Sori separate, round, superficial or slightly immersed, 1.2-4 mm diam.; in 3 or 4 rows between costa and margin, in 2, often alternating rows between the veins on the whole surface of the lamina, paraphyses simple uniseriate hairs with glandular topcells.
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