Thelypteridaceae

Thelypteridaceae is a family of about 900<ref name=FNA/> species of ferns in the order Polypodiales.<ref name=PPGI/><ref name=Christenhusz-2011/><ref name=Smith-2006/> In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is placed in the suborder Aspleniineae.<ref name=PPGI/> Alternatively, the family may be submerged in a very broadly defined family Aspleniaceae as the subfamily Thelypteridoideae.<ref name=ChriChas14/>

The ferns are terrestrial, with the exception of a few which are lithophytes (grow on rocks).<ref name=Smith-2006/> The bulk of the species are tropical, although there are a number of temperate species.<ref name=Smith-2006/>

These ferns typically have creeping rhizomes. The fronds are simply pinnate to pinnate-pinnatifid. There is either no frond dimorphism or only mild dimorphism, either open venation or very simple anastomosing. The sori are mostly reniform in shape and have indusia, except for the Phegopteris group.

Classification

During the early and mid 1900's<ref name="ferns2001">Template:Cite journal</ref> all thelypterioid ferns were included in the genus Dryopteris because of the sorus shape. However, there are a great many differences between the groups, and these plants are now segregated in their own family.<ref name=FNA/><ref name=PPGI/> Genetic evidence shows that the family is clearly monophyletic.<ref name=PPGI/>

Phylogenetic relationships

The following cladogram for the suborder Aspleniineae (as eupolypods II), based on Lehtonen (2011),<ref name=Lehtonen-2011/> and Rothfels & al. (2012),<ref name=Rothfels-2012/> shows a likely phylogenetic relationship between the Thelypteridaceae and the other families of the clade. Template:Eupolypods II cladogram

Genera

The family can be divided into two major clades, which the Pteridophyte Phylogeny Group classification of 2016 (PPG I) recognizes as two subfamilies, Phegopteridoideae and Thelypteroideae.<ref name=PPGI/> Their division into genera has been described as "highly controversial and fluctuating".<ref name=CFLW_Th/> The family includes several complexes of species that are difficult to distinguish, and seem to represent a remarkable evolutionary radiation. Some researchers include the entire family Thelypteridaceae in the genus Thelypteris;Template:Citation needed others divide the family into as many as 30 genera.<ref name=CFLW_Th/> An intermediate position is to place the bulk in Thelypteris (which can then be divided into subgenera and sections corresponding to the genera of other authors) but to separate out Phegopteris and Macrothelypteris.<ref name=FNA/> Another choice is to divide the family into a half a dozen or so genera.<ref name=Smith-2006/>

The Pteridophyte Phylogeny Group classification of 2016 (PPG I) accepts 30 genera:<ref name=PPGI/>

• Subfamily Phegopteridoideae Salino, A.R.Sm. & T.E.Almeid
  • Macrothelypteris (H.Ito) Ching
  • Phegopteris (C.Presl) Fée
  • Pseudophegopteris Ching<ref name=CFLW_Ph/><ref name=POWO_30000947-2/>
• Subfamily Thelypteridoideae C.F.Reed
  • Steiropteris (C.Chr.) Pic.Serm.
  • Tribe Thelypterideae Ching 1963
    • Thelypteris Schmidel
  • Tribe Amauropelteae Wei, Liu & Liu
    • Amauropelta Kunze
    • Coryphopteris Holttum
    • Metathelypteris (H.Ito) Ching
  • Tribe Oreopterideae Wei, Liu & Liu
    • Oreopteris Holub
  • Tribe Leptogrammeae Todaro 1866
    • Cyclogramma Tagawa
    • Leptogramma Smith
    • Stegnogramma Blume
  • Tribe Meniscieae Fée 1850-1852 ex Pfeiffer 1873
    • Subtribe Goniopteridinae Ching 1963
      • Goniopteris C.Presl
    • Subtribe Menisciinae Payer 1850
      • Ampelopteris Kunze
      • Cyclosorus Link
      • Meniscium Schreb.
      • Mesophlebion Holttum
    • Subtribe Pseudocyclosorinae Ching 1963
      • Abacopteris Fée
      • Amblovenatum J.P.Roux
      • Chingia Holttum
      • Christella H.Lév.
      • Glaphyropteridopsis Ching
      • Grypothrix (Holttum 1971) Fawcett & Smith
      • Menisciopsis (Holttum 1982) Fawcett & Smith
      • Menisorus Alston
      • Mesopteris Ching
      • Pakau Fawcett & Smith
      • Parathelypteris (H.Ito) Ching
      • Pelazoneuron (Holttum 1974) Smith & Fawcett
      • Plesioneuron (Holttum) Holttum
      • Pneumatopteris Nakai
      • Pronephrium C.Presl [Nannothelypteris Holttum]
      • Pseudocyclosorus Ching
      • Reholttumia Fawcett & Smith
      • Sphaerostephanos J.Sm.
      • Strophocaulon Fawcett & Smith
      • Trigonospora Holttum

Some species of Pronephrium were split off into other genera in 2021 as a result of a phylogenetic study of the family Thelypteridaceae:<ref name=FawcSmit21>Template:Citation</ref><ref name=FawcSmitSundBurl21>Template:Citation</ref>

• Abacopteris Fée
• Grypothrix (Holttum) S.E.Fawc. & A.R.Sm.
• Menisciopsis (Holttum) S.E.Fawc. & A.R.Sm

The extinct genus Holttumopteris from the Cenomanian aged Burmese amber has been suggested to have affinities with the family, but several important diagnostic characters are not preserved.<ref>Template:Cite journal</ref>