Roots not proliferous. Stems erect, unbranched; scales black with lighter margins, linear-lanceolate, 3--6 × 0.4--0.8 mm, margins entire. Leaves monomorphic. Petiole reddish brown throughout, lustrous, 1--12(--20) cm, 1/3--1/10 length of blade; indument of black filiform scales. Blade linear, 1-pinnate throughout, 5--25(--40) × 1--2.5(--3) cm, thick, glabrous; base gradually tapered; apex acute, not rooting. Rachis reddish brown throughout, lustrous, glabrous. Pinnae in 10--40 pairs, oblong to quadrangular, somewhat asymmetric; medial pinnae 4--15 × 2--5 mm; base rounded to cuneate; margins crenulate or ± entire; apex obtuse. Veins free, obscure. Sori 1(--3) per pinna, only on basiscopic side. Spores 32 per sporangium. n = 2 n = 108 (apogamous). Rock; 50--1000 m; Ala., Ariz., N.C., S.C.; Mexico; West Indies in Hispaniola, Jamaica; Central America; South America to n Argentina; Africa including Madagascar, Madeira, Réunion, Tristan da Cunha; Pacific Islands in Hawaii.