Rhizome 1-2 cm thick, short-creeping, internodes up to 10 cm long. Anatomy: vascular bundles 20-30, c. 4 dorsal strands enlarged, arranged in one row, without dark bundle sheaths, peripheral or central sclerenchyma strands present. Rhizome scales spreading, peltate, monomorphic, 4-8 by 0.7-1.2 mm, index 6-11, apex narrowly acuminate to short-filiform, strongly dentate to short curly-ciliate, midrib absent. Fronds dimorphic, rachises persistent. Base fronds overlapping, contiguous or separate, lobed (sometimes deeply), 10-30 by 7-18(-22) cm, index 1.3-1.7, margin irregularly denticulate. Foliage fronds often slightly internally dimorphic, glabrous, stalked, stipe 10-25 cm long, conspicuously winged, lamina pinnatifid to within 0.5 cm from costa, 40-100 by 20-40 cm, index 2-5, apex aborted or sometimes apical pinna present. Pinnae without basal constriction, gradually smaller towards the apex, 12-25 by (1-)2-3.5 cm, index 6-8, margin entire, apex obtuse to acute, free veinlets simple or forked several times, hydathodes often present. Sori costal, in one row be-tween costa and margin, singly between the veins, round, 2-3 mm, distinctly sunken. Sporangia glabrous. Spores verrucate, without spines or small globules.
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