Thelypteris serrata

Stems short-creeping, 4--10 mm diam. Leaves monomorphic, evergreen, ca. 65--200 cm or more. Petiole tan, (25--)40--120 cm × 4--10 mm, at base with scales absent or ephemeral. Blade 40--100 cm or more, gradually reduced distally with lanceolate apical pinna that is 1/4 to equaling longest lateral pinna; buds sometimes present at base of proximal pinna. Pinnae lanceolate, 15--25 pairs, (10--)15--25 × (1.5--)2.5--3.5(--4.5) cm, rounded to truncate at base, margin hooked-serrate; main lateral veins of fertile pinnae 3--5 per cm, with rows of 10--18 areoles between costa and margin, cross-veins somewhat curved. Indument abaxially of spreading, irregularly crimped hairs ca. 0.2--0.3 mm on costae and sometimes veins adaxially; blades glabrous adaxially. Sori oblong-arcuate, uniseriate between main lateral veins on cross-veins, often appearing confluent at maturity; indusia lacking; sporangia glabrous. 2 n = 72.

Cypress sloughs and swamps; 0--50 m; Fla.; s Mexico; West Indies in the Antilles; Central America; South America to n Argentina.