Plants 5-15 cm tall. Rhizome erect, short, apex scaly; scales dark brown to black, narrowly triangular, 2-3.5 × 0.3-0.5 mm, entire. Fronds caespitose; stipe 2.5-3.5(-6) cm, base scaly and brown abaxially, green upward, adaxially green, sulcate, subglabrous; lamina 2-pinnatifid to 2-pinnate, narrowly triangular-ovate, 8-9 × 2-2.5 cm, base slightly reduced, apex acute; pinnae (5-)10-15 pairs, lower pinnae subopposite, often deltoid-flabellate or almost orbicular, upper alternate and gradually fused into 0.5-1 cm pinnatifid apex, second to fourth pair usually largest, stalk up to 1 mm and adaxially sulcate with raised supravascular ridge, middle pinnae triangular-ovate, ca. 11 × 8-10 mm, base asymmetrical, acroscopic side truncate, basiscopic side cuneate, 1-pinnate, apex obtuse; pinnules 2 or 3 pairs, anadromous, basal acroscopic pinnule free, largest, subovate, 4-5 × 2-4 mm, base cuneate, other pinnules adnate to costa and confluent into pinna apex, margins dentate-serrate, apex obtuse. Veins obscure, flabellately anadromous, slightly raised adaxially. Fronds papery, green to grayish green when dry, lamina subglabrous, average stomatal guard cell length 44-48 µm; rachis semiterete, green, adaxially sulcate and with raised supravascular ridge. Sori 2-4 per pinnule, basal to medial on pinnae, at maturity confluent, linear-elliptic, 1-2.5 mm; indusia grayish green, linear-elliptic, membranous, entire, opening toward costa or costules. Spores with lophate (cristate) perispore, average exospore length 32-34 µm. Plants sexual, allotetraploid: 2n = 144.
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