Plants 10-30 cm tall. Rhizome short, erect or ascending, apex scaly; scales dark brown to black, narrowly triangular, 3-8 × 0.3-0.7 mm, margins denticulate; scale base hyaline, cordate, with numerous yellow-brown, unicellular hairs 1-5 × ca. 0.02 mm, similar to root hairs. Fronds caespitose; stipe 7-15 cm, semiterete, dark brown abaxially or becoming green toward rachis, upward green, adaxially green, shallowly sulcate with supravascular ridge, with similar scales as on rhizome, reduced hairlike scales toward rachis or subglabrous; lamina ovate, 6-13 × 2.5-7(-8) cm, base truncate, apex acute, tripinnatifid-tripinnate; pinnae 8-12 pairs, basal pairs subopposite to alternate, stalk 2-4 mm, sulcate adaxially; several basal pinnae pairs ± equal in length, ovate-triangular, 1.5-3 × 0.5-1.5 cm, base nearly symmetrical, truncate to broadly cuneate, 2-pinnatifid-bipinnate, apex acute; pinnules 4-6 pairs, anadromous, acroscopic and basiscopic pinnules ± equal in size, narrowly triangular to ovate, 5-10 × 3-6 mm, base asymmetrical, acroscopic side truncate, basiscopic side cuneate, largest pinnules stalked, others decurrent on costa, pinnatipartite-pinnate, apex acute; segments 2 or 3 pairs, linear to narrow elliptic, apex with 2 or 3 teeth. Costa sulcate adaxially, without median ridge, veins slightly raised adaxially, anadromously forked. Fronds firmly herbaceous, green to grayish green, lamina subglabrous, average stomatal guard cell length 48-52 µm; rachis green, semiterete, abaxially green or base castaneous becoming green toward apex, adaxially sulcate with raised median supravascular ridge, with reduced scales or subglabrous. Sori 2-4 per ultimate segment, median to subterminal on acroscopic vein, subconfluent at maturity, subelliptic, 1-2.5 mm; indusia grayish green, subelliptic, membranous, entire, opening toward costule or central veinlet, persistent. Spores brown, perispore lophate (cristate), average exospore length 33-36 µm. Plants sexual, allotetraploids: 2n = 144.
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