(L.) J. Sm., Mem. Acad. Roy. Sci. (Turin) 5:420. 1793 Terrestrial, usually 1.5-2 m tall; rhizome horizontal. Leaves 1-pinnate, dimorphic; petioles to ca 1 m long, sparsely to moderately scaly, prominently ridged above; leaflets exactly opposite; sterile leaflets usually narrowly oblong, long-acuminate, obtuse to acute and often slightly inequilateral at base, 10-40 cm long, 4-5.5 cm wide, the margin entire to undulate or faintly serrulate near apex, the midrib sparsely scaly, the scales irregular and deeply lacerate, the lateral veins 1-forked at base; fertile leaflets much shorter and narrower, 1.5-2.5 cm broad. Sporangia in 2 rows, continuous, borne along the veinlets, almost completely covering the fertile leaflets beneath. Croat 12301. Infrequent, on steep moist creek banks in ravines. Mexico to Brazil; West Indies. In Panama, known from tropical moist forest in the Canal Zone, Veraguas, and Panama (San Jose Island), from premontane wet forest in Panama (Chimán) and Veraguas, and from tropical wet forest in Panama. See Fig. 5.