Thelypteris tetragona
Ferns S. E. States 256. 1938.
Stems short-creeping, 3–5 mm diam. Leaves somewhat dimorphic, evergreen, somewhat spaced, fertile leaves long-petioled, more erect, and with more contracted pinnae, to ca. 1.1 m. Petiole straw-colored, to 60 cm × 2–5 mm, at base sparsely set with brown, lanceolate, stellate-hairy scales. Blade 30–45 (–55) × 15–25 cm, broadest at base, with apical pinna similar to lateral pinnae. Pinnae 6–8 (–12) pairs, 7–15 (–18) × 2–3 cm (fertile 1–2 cm), incised 1/2–3/4 of width; segments 3–5 mm wide, rounded at apex; veins 6–10 pairs, proximal pair from adjacent segments united at obtuse angle below sinus with excurrent vein ca. 0.5–1 mm to sinus. Indument abaxially of mostly needlelike hairs 0.1–0.3 mm on costae and veins, blade tissue glabrous on both sides. Sori round, medial to supramedial; indusia lacking; sporangia with numerous hairs 0.1 mm. 2n = 144.
Habitat: Damp woods
Elevation: 0–50 m
Distribution
Fla., Mexico, West Indies in the Antilles, Central America to Panama, n South America
Discussion
Selected References
None.
Lower Taxa
No values specified."/2" is not declared as a valid unit of measurement for this property.