Stems long-creeping, ropelike; scales dark brown, few, triangular. Leaves monomorphic, deciduous, numerous, well separated, 50-100 cm. Petiole dark purple to black proximally, straw-colored distally, base lustrous and swollen, glabrate. Blade greenish, lanceolate, 28-60 cm, bearing mixture of glands and scales upon emergence with glands persisting. Pinnae articulate to rachis, arranged in 12-23 evenly distributed pairs, linear to narrowly lanceolate, deeply pinnatifid; middle pinnae 6-16 × 1-3.5 cm. Veins anastomosing to form a single row of areoles, then free to margin. Sori elongate, linear, superficial, often appearing confluent upon dehiscence of sporangia. Indusia ± membranous, lacking thickened cells, freely spreading, often hidden by dehisced sporangia. 2 n = 70.

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• 1
]. 

"Rhizome 6–10 mm thick; lvs monomorphic, to 14 dm, the petiole purplish-brown, shining, the blade lance-oblong, to 5 × 2.5 dm, acuminate, pinnate- pinnatifid, the pinnae 15–20 pairs, pinnatifid with a rachis 1–1.5 mm wide, the segments 15–20 pairs, ovate to broadly oblong, with cartilaginous margins; veins forming a single series of areoles along the costa and costules, otherwise free, indusia thin, soon recurved, those along the costules only 1–1.5 mm, those along the costae larger; 2n=70. Swamps and moist places in acid soil; N.S. to Fla., w. to Ont., Mich., Ill., and Tex.; Bermuda. (Anchistea v.)"

Source: [
• 2
].