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Rhizome erect or ascending; rhizome scales lanceolate to linear-lanceolate in outline, 3–4 mm long, narrowly dark in the middle with pale edges. Fronds (1–)few, tufted, 0.3–1 m tall. Stipe 10–38 cm long with scales near base. Lamina triangular, 20–40 x 15–40 cm wide with a gemma near the base of the terminal pinna. Pinnae in 1–5 pairs, typically (but apparently not in E Africa) the pinnae simple, 6–19 x 1.4–4 cm, entire or with a few coarse lobes and basal pair with a basiscopic spur; more usually the pinnae are deeply pinnatifid and in W Africa simple and pinnatifid fronds often occur on the same plant with every intermediate; pinnae oblong-lanceolate in outline, 13–22 x 3–8 cm, the terminal segments narrowly triangular-lanceolate, 3–6(–9) x 1 cm, crenulate at the apex; ultimate segments of pinnae in 10–15 pairs, oblong in outline, 0.6–4.5 x 0.5–1.1 cm, ± rounded and crenate-serrate at the apex, the basal basiscopic segment of lowest pinnae much longer, 7.4 x 1.4 cm; costa of pinnae ± smooth on both sides save for very sparse roughening and a small patch of dense short emergences where base of pinna meets the rhachis; rhachis narrowly winged by decurrent pinna bases; veins in segments usually densely anastomosing. Sori often running along whole margin of pinna whether simple or deeply pinnatifid without a gap in sinuses and then up to 20 cm long, but tips of ultimate segments usually sterile and crenate and sori usually U-shaped and 2–5 cm long.
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