Terrestrial, to 90 cm tall; rhizome stout, creeping, the petiole bases very close together. Leaves 1-pinnate; petioles slender, to 45 cm long, densely scaly, the scales fine, short; leaflets +/- lanceolate-elliptic, acuminate, variable and often inequilateral at base, mostly 20-30 cm long and 5-10 cm wide, entire to undulate or irregularly lobed, glabrous or septate-pilose or hirsute on both surfaces, the basal pair of leaflets with a large, basiscopic lobe; smaller veins reticulate. Sori round, usually in irregular rows alongside each major lateral vein; indusium round-peltate, pubescent. Croat 12299. Abundant throughout the forest and at the margins of clearings. The species is probably the most abundant terrestrial fern of the island. Costa Rica to Colombia at low elevations. In Panama, known principally from tropical moist forest in the Canal Zone, Bocas del Toro, Colon, San Blas, Chiriqui, Veraguas, Los Santos, Panama, and Darien, but also from premontane wet forest in Coclé and Panama, from tropical wet forest in Chiriqui and Panama, and from lower montane wet forest in Chiriqui. See Fig. 38.