Thelypteris decussata (L.) Proctor

  • Authority

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

  • Family

    Thelypteridaceae

  • Scientific Name

    Thelypteris decussata (L.) Proctor

  • Description

    Species Description - Rhizome erect or curved-ascending, succulent woody, up to 3 cm thick or more (excluding dense root-mass and bases of stipes), the apex bearing large, lance-attenuate, light brown, glabrous scales up to 10 mm long, the whole apex (including the scales) covered when living with copious gelatinous mucilage. Fronds erect-arching, up to 3.5 m long; stipes stout, to 1.2 m long, purplishbrown, minutely glandular-pubemlous and bearing (especially toward base) scattered, thin, brownish scales. Blades oblong, 1-2.8 m long, 50-90 cm broad, acuminate at apex, truncate at base; rhachis minutely stipitate-glandular and sparsely puberulous, as are the costae abaxially; pinnae ligulate-caudate, deeply pinnatifid with nanow acute sinuses, each subtended at base by a stout, brown, horny aerophore; costae densely pubescent on adaxial side; segments liguliform, 15-22 mm long, 3-4 mm wide, the margins entire and densely ciliate, each subtended at base by a linear brown aerophore; tissue densely resinous- glandular abaxially, sparsely hirtellous above; veins 25-50 pairs per segment, simple. Sori small but becoming confluent at maturity, forming a dense inframedial line; indusium absent; sporangia glabrous.

  • Discussion

    Fig. 58.

    Basionym. Polypodium decussatum Linnaeus, Sp. pl. 2: 1093. 1753.

    Lectotype. Petiver, Pter. Amer., t. 2, fig. 5, copied from Plumier, Traite foug. Amer., t. 24, based on a plant from Martinique.

    Syn. Glaphyropteris decussata (Linnaeus) K. Presl ex Fee, Crypt, vase. Bresil 2: 40, 1873.

    Phegopteris decussata (Linnaeus) Mettenius, Fil. hort. bot. Lips. 83, t. 17, fig. 8. 1856.

    Gymnogramma decussata (Linnaeus) Fee, Mem, foug. 7:44. 1857.

    Nephrodium decussatum (Linnaeus) Diels in Engler & Prantl, Nat. Pflanzenfam. 1(4): 171.1899.

    Bryopteris decussata (Linnaeus) Urban, Symb, Antill, 4: 19, 1903.

  • Distribution

    General Distribution. Greater and Lesser Antilles, Trinidad, and continental tropical America.

    West Indies| Central America| South America|