Rhizome long-scandent, 0.75-2 mm ø, dark brown, deciduously scaly; scales dorsally more persistent, golden brown to fawn-coloured, triangular, to 3 by 1 mm, to c. 22-seriate at the base, there the cell partitions sometimes bulging beyond the margin, the apex very shortly uniseriate. Leaves rather remote, 0.5-4 cm apart; petioles dark or reddish brown, or paler above, abaxially terete at the base, upward gradually bi-angular, laterally often sulcate, adaxially flattened to shallowly sulcate, 1-5(-10) cm long, much shorter than the lamina. Lamina linear, tapering at both ends, (10-)15-40 cm long, (1.5-)2-3 cm wide, with c. 20-60 pinnules to a side; rachis stramineous, quadrangular, adaxially at least upward sulcate. Pinnules thinly herbaceous, dark green to olivaceous or blackish when dry, spreading or falcately deflexed, rarely ascending, rather close or contiguous, approximately 1/4-elliptic in outline, the larger ones (7-) 10-15 by 3-5 mm, 2-3 times as long as wide; upper margin outward gradually more convex, deeply incised, larger pinnules consisting of 4-5 primary segments, the inner, larger ones usually forked (occasionally twice forked); ultimate segments divergent, linear-cuneate, 0.5-2 mm wide at the apex, narrowed just below the sorus, little or not narrowed to the base, there connected by wings of 1/4-1/2 mm; apex segments truncate-sinuate or-erose, not rarely with two slightly larger lateral protuberances, sometimes also with 1-2 smaller ones between them. Few upper pinnules reduced and confluent into a pinnatifid leaf-apex; some to many basal ones remote and gradually reduced, usually inserted just below the lateral ridges of the adaxial rachis face. Veins immersed, evident, single or paired in the ultimate lobes. Sori uni-or not rarely binerval; indusium thin, pale to brown, subentire, 0.5-2 mm long, 0.4 mm wide, at least laterally convex at the base, not reaching the margin by about its width to almost reaching it, not reflexed at maturity. Spores very pale brown, trilete, smooth, c. 25 μ.
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