Pteris tripartita Sw.

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.

introduced, naturalized in scattered locations; Fla.; West Indies; Central America; South America; native to tropical Asia.

Terrestrial in cypress, pond-apple, and other swamps or forested wet habitats, on constantly moist, circumneutral soils; 0--50m.

Litobrochia tripartita (Swartz) C. Presl

Crece en las orillas de los ríos y en zonas abiertas.

Distribucion en Costa Rica: En las Llanuras del Norte y Caribe, Península de Osa e Isla del Coco a una altura de 0 a 1.200 m.
Distribucion General: Panamá, Colombia, Venezuela, Guayanas, Ecuador, Perú, Antillas, Paleotrópicos.

Helecho terrestre.

Rizoma de 5 a 15 mm de diámetro, erecto. Frondas de 0,3 a 2,5 m de largo. Pecíolo más largo que la lámina, glabro, inerme, pajizo a pardo. Lámina de 35 a 100 por 30 a 80 cm, partida en 3 ó 4, pedadamente ramificada, cartácea, la base truncada.

Pinnas basales 1-pinnado-pinnatífidas más allá de las pínnulas basales, la pínnula basiscópica muy agrandada, partida en 2 o 3. Pinnas suprabasales de 15 a 25 pares, de 2 a 4 cm de ancho, pinnatisectas, la base sésil. Ultimos segmentos de (2) 4 a 5 mm de ancho en el centro, rectos o ligeramente falcados, el ápice entero o someramente crenado, agudo a obtuso.

Raquis y costa pajizos a pardos, glabros o esparcidamente pelosos, inermes, los tricomas de 0,1 a 0,2 mm, adpresos, rojizos en las uniones celulares. Nervaduras areoladas a lo largo de la costa, con 1 aréola entre cóstulas adyacentes, pero libre de aréolas hacia los márgenes. Soros cubriendo buena parte del margen de los segmentos, con el ápice completamente libre.

Localidad del tipo: Java
Depositario del tipo: UPS
Recolector del tipo: Thunberg ( s. n.)

Pteris tripartita is a species of fern native to Africa, Indonesia, and the Marquesas.

Pteris tripartita là một loài thực vật có mạch trong họ Pteridaceae. Loài này được Sw. miêu tả khoa học đầu tiên năm 1801.

三叉凤尾蕨（学名：Pteris tripartita）为凤尾蕨科凤尾蕨属的植物。分布在斯里兰卡、菲律宾、印度、马来西亚、中南半岛、澳大利亚、台湾岛、非洲、波利尼西亚、印度尼西亚以及中国大陆的海南等地，目前尚未由人工引种栽培。