Monographs Details: Polypodium
Authority: Mickel, John T. & Beitel, Joseph M. 1988. Pteridophyte Flora of Oaxaca, Mexico. Mem. New York Bot. Gard. 46: 1-580.
Scientific Name:Polypodium
Description:Genus Description - Epiphytic or epipetric, infrequently terrestrial; rhizome short- to long-creeping, freely branched, often glaucous, root proliferations absent; rhizome scales concolorous to bicolorous, clathrate or not, peltately attached, surface glabrous or hairy, margin entire or toothed; fronds pinnatifid to pinnate, infrequently more divided, segments few, lanceolate, rarely numerous, distant, monomor-phic to subdimorphic, stipitate, articulate on phyllopodia; stipe stramineous, rarely dark, channelled (never terete); blade glabrous, hairy or scaly; veins free or netted, if netted, regular areoles with single, free, included vein; sori round to oblong, exindusiate, paraphyses (abortive sporangia or branched, filamentous) present or absent, terminal on lowest acroscopic vein or free included vein if areolate, in one to several rows between costa and margin; sporangia with paraphyses or glabrous; spores bilateral, verrucate, tuberculate, rugose or papillate.

Discussion:Marginaria Bory, Diet, class, hist. nat. 6: 587. 1824. Lectotype (chosen by ?): Marginaria ceteraccina (Michaux) Bory [=Polypodium polypodioides (Linnaeus) Watt]. Lepicystis (J. Smith) J. Smith, London J. Bot. 1: 195. 1842. Goniophlebium sect. Lepicystis J. Smith, J. Bot. (Hooker) 4: 56. 1841. Type: Lepicystis incana (J. Smith) J. Smith, = Goniophlebium incanum J. Smith, =Polypodium incanum Swartz, nom. superfl., =Polypodium polypodioides (Linnaeus) Watt]. Polypodium, as defined in the narrow sense, comprises about 100-125 species, mostly of the New World tropics with a few species in the temperate regions of America, Europe, Asia and Africa. The species have pinnatifid to pinnate (rarely simple) fronds, peltate rhizome scales, free or netted venation with single free included veins, sori terminal on the end of veins or on a free included vein, channelled stipes, filamentous or branched paraphyses and branched rhizomes. The limits of the various generic segregates of Polypodium here recognized (q.v.) and keyed below (Campyloneurum, Microgramma, Niphi-dium, Pecluma, Phlebodium and Pleopeltis) are problematic. References: de la Sota, E. R. 1966. RevisiĆ³n de las especies americanas del grupo Polypodium squamatum L. Revista Mus. La Plata, Secc. Bot. 10: 69-186; Max-on, W. R. 1903. A study of certain Mexican and Guatemalan species of Polypodium. Contr. U.S. Natl. Herb. 8: 271-280; Maxon, W. R. 1916. Studies of tropical American ferns. No. 6. Contr. U.S. Natl. Herb. 17: 541-608.