Plants 10-23 cm tall. Rhizome short, erect or ascending, apex scaly; scales dark brown to black, narrowly triangular, 2-4(-6) × 0.3-0.7 mm, margins denticulate; scale base hyaline, cordate, with yellow-brown, unicellular hairs 1-5 × ca. 0.02 mm, similar to root hairs. Fronds caespitose; stipe 7-10 cm, semiterete, base dark brown abaxially, upward green, adaxially yellow-green, sulcate with pronounced supravascular ridge, with similar scales as on rhizome, reduced hairlike scales toward rachis or subglabrous; lamina triangular-ovate, 6-15 × 2.5-7 cm, base truncate, apex acute, tripinnatifid-tripinnate; pinnae 8-12 pairs, basal pairs subopposite to alternate, stalk 1-3 mm, sulcate but with median supravascular ridge adaxially; basal pinnae equal or slightly shorter than next, ovate-triangular, 1.5-4.5 × 1.5-3 cm, base nearly symmetrical, truncate to broadly cuneate, bipinnatifid-bipinnate, apex acute; pinnules 4-6 pairs, anadromous, basal pinnules ± equal in size, narrowly triangular to ovate, 5-20 × 4-7 mm, base asymmetrical, acroscopic side truncate, basiscopic side cuneate, stalk up to 1 mm or decurrent on costa, pinnatipartite-pinnate, apex acute; segments 3 or 4 pairs, linear, 1.5-5 × 0.5-2 mm, basal segments forked or up to pinnatisect with 2 or 3 ultimate segments, apex of segments with 2 or 3 teeth. Costa sulcate adaxially, with distinctly raised median supravascular ridge, veins raised adaxially, veins anadromously forked. Fronds thinly to firmly herbaceous when dry, green to grayish green, lamina subglabrous, average stomatal guard cell length 35-43 µm; rachis green, semiterete, adaxially sulcate with raised median supravascular ridge, with reduced scales or subglabrous. Sori 1 or 2 per ultimate segment, median to subterminal on acroscopic vein, near segment teeth but not reaching margin, subconfluent at maturity, subelliptic, 1-2 mm; indusia grayish green, subelliptic, membranous, entire, opening toward costule or central veinlet, persistent. Spores brown, perispore lophate (cristate), average exospore length 28-30 µm. Plants sexual diploids: 2n = 72*.
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