Plants 15-40 cm tall. Rhizome erect, short, apex scaly; scales blackish brown, narrowly triangular, costate, with or without median opaque zone, margin fimbriate or entire. Fronds caespitose; stipe castaneous-brown to purplish black, shiny, 5-15(-21) cm, terete to tri-or tetragonous; lamina linear-lanceolate, 12-14(-28) × 2-3(-3.6) cm, 1-pinnate; pinnae 20-30(-44) pairs, alternate, sessile, middle pinnae trapeziform to oblong, 8-18 × 4-8 mm, base asymmetrical, acroscopic side truncate and subauriculate, basiscopic side narrowly cuneate, margin repand or crenate to serrate, apex obtuse; basal pinnae often somewhat reflexed, occasionally reduced. Costa with anadromously pinnate venation but with first basiscopic vein lacking, obscure, or faintly visible, veins simple or 2-forked. Fronds herbaceous to thinly papery, brownish green or grayish green when dry, (sub)glabrous; rachis castaneous-brown, subglabrous, often compressed after drying, adaxially with a deep furrow with rounded lateral edges, abaxially terete or keeled, often gemmiferous near apex. Sori 3 or 4(-6) per pinna, linear-elliptic, 2-2.5(-3) mm, median on subtending vein; indusium brown or grayish brown, semi-elliptic, membranous, entire, opening toward costa. Spores with lophate (cristate to alate) perispore, with perforated crests. Plants sexual: 2n = 72, 144, 216, or 288.
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Lithophytic fern. Rhizome erect, scaly. Stipe and rachis shiny, dark brown throughout, ± glabrous; stipe 3–12 cm long, c. 0.5 mm diam. Lamina very narrowly elliptic to ± linear, pinnate, 8–12 cm long, 1.7–2.3 cm wide, thin, ± glabrous. Pinnae in 15–25 pairs, ± oblong; bases unequally cuneate, lobed acroscopically and excised basiscopically, shortly stalked; apices obtuse; acroscopic and apical margins coarsely crenate-serrate; basiscopic margins entire; longest pinnae near middle, 8–12 mm long, 5–7 mm wide, decreasing gradually upwards to a short acuminate pinnatifid apex; lowest pinnae deflexed. Sori to 2 mm long. Perispores dark, reticulate, fenestrate with occasional ridges; exospores 34.6–34.8 × 22.7–23.4 µm (means).
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