Grammitis

• Authority

  Mickel, John T. & Beitel, Joseph M. 1988. Pteridophyte Flora of Oaxaca, Mexico. Mem. New York Bot. Gard. 46: 1-580.

• Family

  Polypodiaceae

• Scientific Name

  Grammitis

• Description

  Genus Description - Mostly epiphytic, rarely terrestrial or epipetric at high elevation; rhizome erect to creeping, scaly, rarely glabrous; fronds small, clumped to distant, not articulate, monomorphic to hemidimorphic; stipe very slender, often with straight reddish-brown hairs, rarely glabrous; blade undivided (linear to narrowly elliptic), mostly pinnatifid to once-pinnate, or rarely bipinnate to tripinnate; lamina thin to coriaceous, often with long, straight hairs, glabrous in some species; veins free (netted only in a few species with undivided blades), ending in a distinct hydathode in some species, some with lime dots on the hydathodes; sori dorsal, round to elongate, usually discrete, indusia lacking, pa-raphyses lacking, sometimes sori elongate along base of veins, by the rachis or costa, or in grooves of lamina; sporangium with erect annulus, glabrous or setose, stalk 1-cell thick; spores tetrahedral-globose, green, perispore lacking.

• Discussion

  Lectotype (chosen by Christensen, Index filic, xliv. 1906): Grammitis marginella (Swartz) Swartz [=Polypodium marginellum Swartz]. Ctenopteris Kunze, Bot. Zeitung (Berlin) 1846: 425. 1846. Lectotype (chosen by Copeland, Gen. fil. 218. 1947): Ctenopteris venulosa (Blume) Kunze [=Polypodium venulosum Blume]. For further details, see Morton (Amer. Fern J. 56: 65-68. 1966). Grammitis is a pantropical genus of about 400 species, with about half in the New World, of wet forests, mostly of middle to upper elevations. Previous subdivision of the genus has not been entirely satisfactory (Copeland, 1947; Pichi Sermolli, 1977), based on blade dissection into Grammitis, Xiphopteris, and Ctenopteris. Most recent workers have lumped these into Grammitis. Cochlidium (including Xiphopteris) was recognized by Bishop (1978) and is kept separate here (q.v.) although the species of Cochlidium appear with Grammitis in the following key. Grammitis closely resembles Polypodium in blade dissection and naked sori, but is distinguished by generally smaller size, stiff, reddish-brown blade hairs and green, trilete spores. References: Bishop, L. E. 1978. Revision of the genus Cochlidium (Grammitidaceae). Amer. Fern J. 68: 76-94; Copeland, E. B. 1947. Genera Filicum. Chronica Botanica, Waltham, Mass.; Copeland, E. B. 1952. The American species of Xiphopteris. Amer. Fern J. 42: 41-52, 92-110; Copeland, E. B. 1955 [1956]. Ctenopteris in America. Philipp. J. Sci. 84: 381-473; Max-on, W. R. 1914. Notes upon Polypodium duale and its allies. Contr. U.S. Natl. Herb. 17: 398-406. Maxon, W. R. 1916. Polypodium trichomanoides and its American allies. Contr. U.S. Natl. Herb. 17: 542-557; Morton, C. V. 1967. The genus Grammitis in Ecuador. Contr. U.S. Natl. Herb. 38: 85-123; Pichi Sermolli, R. E. G. 1977. Tentamen pteridophytorum genera in taxonomicum ordinem redigendi. Webbia 31: 313-512.