Polypodium

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For the animal genus, see Polypodium (animal).
iPolypodium
Polypodium vulgare
Polypodium vulgare
Scientific classification
Kingdom: Plantae
Division: Pteridophyta
Class: Pteridopsida
Order: Polypodiales
Family: Polypodiaceae
Genus: Polypodium
L.
Species

See text

Polypodium is a genus of between 75-100 species of true ferns, widely distributed throughout the world, with the highest species diversity in the tropics. The name is derived from Gr. poly, many, and podium, a little foot, on account of the foot-like appearance of the rhizome and its branches.

They are terrestrial or epiphytic ferns, with a creeping, densely hairy or scaly rhizome bearing fronds at intervals along its length. The species differ in size and general appearance and in the character of the fronds, which are evergreen, persisting for 1-2 years, pinnate or pinnatifid (rarely simple entire), and from 10-80 cm or more long. The sori or groups of spore-cases (sporangia) are borne on the back of the frond; they are globose and naked, not covered with a membrane (indusium).

Selected species
  • Polypodium amorphum Suksdorf
  • Polypodium appalachianum Haufler & Windham
  • Polypodium asterolepis Baker
  • Polypodium californicum Kaulf.
  • Polypodium calirhiza S.A.Whitmore & A.R.Smith
  • Polypodium cambricum L. (syn. P. australe Fée)
  • Polypodium excavatum Roxb.
  • Polypodium feei (Bory) Mett.
  • Polypodium furfuraceum Schltdl. & Cham.
  • Polypodium glycyrrhiza D.C.Eaton
  • Polypodium hesperium Maxon
  • Polypodium interjectum Shivas
  • Polypodium lepidopteris (Langsd. & Fisch.) Kunze
  • Polypodium leucotomos
  • Polypodium macaronesicum Bobrov
  • Polypodium nigrescens Blume
  • Polypodium phymatodes L.
  • Polypodium saximontanum Windham
  • Polypodium scouleri Hooker & Greville
  • Polypodium sibiricum Sipliv.
  • Polypodium triseriale Swartz
  • Polypodium virginianum L.
  • Polypodium vulgare L. (Common Polypody)

Several of the species form hybrids with other species in the genus; these may often be distinguished by being sterile, with very small, blind sori. Named hybrids include P. × font-queri (P. cambricum × P. vulgare), P. × mantoniae (P. interjectum × P. vulgare), and P. × rothmaleri (P. cambricum × P. interjectum).

A number of species formerly included in the genus have recently been transferred to other genera, including Campyloneurum, Microgramma, Neurodium, Pecluma, Phlebodium, and Pleopeltis.

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