Rhizome rather short-creeping, 2 mm ø; scales reddish brown, narrowly triangular, acuminate, to 2.5 mm long, to c. 10-seriate at base, the apical uniseriate part relatively short. Leaves rather close; petioles 8-35 cm long, about equaling the lamina, stramineous to fawn-coloured, quadrangular, with paler edges, ± sulcate. Lamina bipinnate (rarely subtripinnate), with 3-5 pinnae to a side and a conform terminal one. Primary rachis similar to the petiole, abaxially narrowly channelled. Pinnae obliquely ascending, not close, subsessile, 10-15 cm long, 1.5-2.5 cm wide, narrowed in the upper 1/3, the upper ones little shortened; basal pinnae rarely with 1 or 2 basal pinnate secondary pinnae. Secondary rachises abaxially bi-angular. Pinnules c. 20-30 to a side, mostly not contiguous, herbaceous, dark green when dry, semi-ovate to subtrapeziform, subsessile, 9 by 3 to 12 by 4.5 mm, 2.5-3 times as long as wide, the lower margin ± straight, the upper straight or slightly convex, a distinct outer margin not or scarcely developed. Upper pinnules gradually and strongly reduced, several denticuliform ones connected with the narrow terminal segment. Upper margin of pinnules mostly with 3 oblique incisions which scarcely reach farther than 1/4 but get slightly deeper towards the apex of the pinnule; outer margin without or with one incision. Larger pinnule lobes with a straight or sinuate outer margin, laterally somewhat convex; sinus acute. Veins immersed, evident, mostly once forked. Sori one per lobe, mostly binerval, laterally exceeding the vein-ends; indusium entire, 1/4-1/3 mm wide, almost or quite reaching the margin, scarcely reflexed at maturity. Spores pale brown, trilete, smooth, c. 28 μ.
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