Thelypteris dentata (Forssk.) E.P.St.John

  • Authority

    Acevedo-Rodríguez, Pedro & collaborators. 1996. Flora of St. John, U.S. Virgin Islands. Mem. New York Bot. Gard. 78: 1-581.

  • Family

    Thelypteridaceae

  • Scientific Name

    Thelypteris dentata (Forssk.) E.P.St.John

  • Description

    Species Description - Terrestrial fern 0.5-1.2 m tall. Rhizome short-creeping, ca. 6 mm thick, closely covered with persistent stipe bases, at apex bearing a tuft of dark brown, distantly ciliate, linear-attenuate scales, 4-10 mm long. Fronds slightly dimorphic, the fertile ones a little taller and with narrower pinnae than the sterile ones, to 1.2 m long; stipes 15-45 cm long, minutely puberulous throughout, and toward base bearing dark brown, linear-lanceolate scales, these ciliate and often also with surface hairs. Blades 40-90 x 14_34 Cm, tapering evenly to the pinnatifid apex, at base the proximal 2-6 pairs of pinnae reduced and somewhat reflexed; rachis densely pubescent with curved hairs but without scales; largest pinnae 7-19 x 1.1-2.7 cm, attenuate at apex, sessile, pinnatifid; segments oblong or oblong-subfalcate, 2-4 mm broad, blunt to acute at apex, entire; veins 6-10 pairs, all simple; midveins, midveinlets, and veins curved-pubescent on upper side, finely puberulous beneath, with hairs to 0.2 mm long; tissue light green, soft-herbaceous, not glandular. Sori nearly medial; indusium round to kidney-shaped, pubescent, nonglandular; sporangia glabrous but their stalks often bearing orange, stipitate glands.

    Distribution and Ecology - Occasional in moist, disturbed habitats. Visually recorded by G. R. Proctor. Also on St. Croix, St. Thomas, and Tortola; apparently indigenous to the Old World but now pantropical.

  • Discussion

    Polypodium molle Jacq., Collectanea 3: 188. 1789, non Schreb., 1771, nee AIL, 1785. Aspidium molle Sw., J. Bot. (Schrader) 1800(2): 34. 1801. Nephrodium molle (Sw.) R. Br., Prodr. 149. 1810. Polystichum molle (Sw.) Gaudich., Voy. Uranie 326. 1828. Hemesthenum molle (Sw.) Gand. Fl. Eur. 27: 178. 1891. Dryopteris mollis (Sw.)Hieron., Hedwigia 46: 348. 1907.