Amer. Fern J. 12: 75. 1922.
Stems creeping, 4–8 mm diam. Leaves monomorphic, evergreen, (0.5–)1–3.5 cm apart, (30–)65–140 cm. Petiole straw-colored, 15–70 cm × 2–7(–9) mm, at base with scales tan to brownish, linear-lanceolate, hairy at margin. Blade 30–70 cm, broadest at or near base, abruptly narrowed distally, apical pinna ± similar to lateral pinnae, 5–17 × 1–3(–5) cm. Pinnae (4–)10–22(–28) × (0.3–)0.7–1.5 cm, incised 1/2–3/4 of width; segments somewhat curved, margins revolute, those at base of proximal pinnae slightly elongate; proximal pair of veins from adjacent segments running to sinus. Indument abaxially of hairs 0.2–0.4 mm on costae, veins, and blade tissue, also of brownish scales 0.6–1.2 mm on costae; veins and blade tissue glabrous adaxially. Sori round, medial to supramedial; indusia tan, bearing hairs 0.2–0.4 mm; sporangia glabrous. 2n = 144.
Habitat: Limestone banks, in sun or partial shade
Elevation: 0–50 m
Fla., s Mexico, West Indies in the Bahamas, Cuba, Central America in Guatemala.
Thelypteris augescens occasionally hybridizes with T. kunthii and T. ovata var. ovata in southern Florida.