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Pteris tripartita
Swartz, J. Bot. (Schrader). 1800(2): 67. 1801.
Giant brake
Litobrochia tripartita
(Swartz) C. Presl
Stems stout, short-creeping, densely and conspicuously scaly; scales pale brown. Leaves clustered, 1--2 m. Petiole straw-colored to brownish red, to more than 1 m, scaly proximally, otherwise glabrous at maturity. Blade deltate to pentagonal, pedate, ultimate divisions pinnately divided, 1--2 × 1--2 m; rachis not winged. Pinnae few, closely spaced, remaining green through winter, not decurrent on rachis, not articulate to rachis, oblong-lanceolate, 1--3-forked, to 7 × 6 dm; base asymmetrical, acute; apex acute; rachis and costae glabrate or with minute hairs, especially near axils of proximal pinnae; penultimate pinnules linear to linear-lanceolate, pinnatifid, separated, not remaining green through winter, not articulate to rachis. Ultimate segments of blade numerous, linear-oblong to linear-lanceolate, to 19 × 6 mm, margins entire or serrulate, apex obtuse and rounded to acute; terminal segments 3--4 cm longer and more tapering than lateral segments. Veins anastomosing near costae and costules, becoming forked and free near margins of ultimate segments. Sori narrow, blade tissue exposed abaxially.
Terrestrial in cypress, pond-apple, and other swamps or forested wet habitats, on constantly moist, circumneutral soils; 0--50 m; introduced, naturalized in scattered locations; Fla.; West Indies; Central America; South America; native to tropical Asia.
