Terrestrial or aquatic, to 1.3 m tall; rhizome very stout, +/- erect, the petiole bases moderately close together, but only a few leaves borne at any one time. Leaves 1-pinnate; petioles as long as or much longer than blades, glabrous to sparsely pubescent, the trichomes simple; rachis more densely pubescent; leaflets narrowly oblong to oblong-lanceolate, acuminate, acute to rounded at base, sessile or with petiole to 1 cm long, mostly (13) 20-25 (35) cm long and (1.5) 3-4 cm wide near middle of blades, only slightly reduced toward base, much decreased upward, the margins uncinate-serrate to entire, glabrate to sparsely pubescent especially on the veins below, the trichomes stiff, straight; veins meniscoid. Sori much longer than broad, curved, exindusiate, the sporangia borne along most opposing pairs of veinlets between the major lateral veins. Croat 5253. Occasional, on eroding banks near the edge of the shore and locally common in floating masses of vegetation along the shores on the south side of the island; elsewhere in the Canal Zone, common on roadbanks.