Sp. Pl. 2: 1069. 1753.
Stems creeping or ascending, frequently branched. Leaves ± arching, 1–3 m × 12–50 cm. Rachis rounded abaxially, decidedly grooved adaxially. Pinnae 24–30 (–40), usually not overlapping, 10–34 × 1.3–7 cm; proximal pinnae always distant, frequently rounded at tip; costal areoles 3 or more times longer than wide; distal 6–12 pinnae of fertile leaves bearing sporangia. Sporangia spread over abaxial surface of distal pinnae in fertile leaves; paraphyses stalked, ending with single isodiametric, irregularly lobed cell. Spores (37–) 57 (–72) µm diam., surface minutely tuberculate. 2n = 60.
Phenology: Sporulating all year.
Habitat: Coastal mangrove swamps, salt marshes, low hammocks, along lake and canal margins
Elevation: 0–50 m
Fla., worldwide in tropical and subtropical regions