Polypodium polypodioides (L.) Walter

  • Authority

    Proctor, George R. 1989. Ferns of Puerto Rico and the Virgin Islands. Mem. New York Bot. Gard. 53: 1-389.

  • Family

    Polypodiaceae

  • Scientific Name

    Polypodium polypodioides (L.) Walter

  • Description

    Species Description - Rhizome wide-creeping, often branched and forming loose mats, densely clothed with mostly bicolorous, lance-subulate to ovate-acuminate scales 2-4 mm long, with dark brown median stripe and broad, pale brown to whitish marginal zones having erose ciliate margins. Fronds widely spaced on rhizome, 6-20 cm long; stipes 2-8 cm long, densely appressed-scaly, shorter than to equalling the blades. Blades oblong or narrowly deltate-oblong, 4-15 cm long, 1.5-6 cm broad, deeply pinnatisect, narrowed to a blunt or acutish apex, tmncate at base; rhachis scaly like the stipe; segments 6-17 pairs, linear or narrowly oblong, 2.5-5 mm broad, obtuse at apex, dilated at base and joined by a broadly rounded sinus; veins mostly 2- or 3-forked, free or partly reticulate and forming a single row of areoles on either side of the costa, obscure and difl&cult to observe; tissue dull green, opaque, the adaxial side sparsely and minutely scaly (appearing naked), the abaxial side densely covered with overlapping scales, these roundish to deltate-ovate, peltately attached. Entire blade strongly hygro-elastic, curling up tightly during dry periods, then expanding after rain or sometimes at night. Sori supramedial, protruding from shallow pits in the tissue, uniseriate on either side of the costa.

    Distribution and Ecology - General Distribution. Bahamas, Greater Antilles, Cayman Islands, Lesser Antilles, and continental tropical America from Mexico to Costa Rica and Venezuela. This distribution pertains to var. polypodioides; several other named variants occur in chiefly continental areas from eastern temperate North America to Argentina. Distribution in Puerto Rico. Of wide occurrence, and probably grows in all municipios; recorded from Adjuntas, Aibonito, Arecibo, Barranquitas, Bayamon, Cayey, Ciales, Isabela, Juana Diaz, Maricao, Ponce, Vega Alta, Villalba, Yabucoa, and Yauco. Virgin Islands. St. Croix and St. Thomas. Habitat. On rocks (including old stone walls) and trees at low to upper middle elevations (140-860 m), common.

  • Discussion

    Fig. 92.

    Basionym. Acrostichum polypodioides Linnaeus, Sp.pl. 2: 1068. 1753.

    Lectotype. Plukenet, from Jamaica (BM; selected by Weatherby, 1939).

    Syn. Polypodium incanum Swartz, Prodr. 131. 1788. (An illegitimate renaming of Acrostichum polypodioides Linnaeus.)

    Polypodium ceteraccium Michaux, R. bor.-amer. 2: 271. 1803. (Based on Acrostichum polypodioides Linnaeus.)

    Polypodium velatum Schkuhr, Krypt. Gew. 1: 188, t. lib. 1809. (A doubtfully intended renaming of P. incanum Swartz.)

    Lepicystis incana (Swartz) J. Smith, London J. Bot. 1: 195. 1842.

    Marginaria polypodioides (Linnaeus) Tidestrom, Torreya 5: 171. 1905.