Cheilanthoideae is one of the five subfamilies of the

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

family

Pteridaceae Pteridaceae is a family of ferns in the order Polypodiales, including some 1150 known species in ca 45 genera (depending on taxonomic opinions), divided over five subfamilies. The family includes four groups of genera that are sometimes recogni ...

. The subfamily is understood to be

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

, but some of the genera as currently defined are not. Most species are xeric-adapted, and the subfamily is most diverse in dry areas.

Phylogenic relationships

The following phylogram shows a likely relationship between Cheilanthoideae and the other Pteridaceae subfamilies. Although subfamily Cheilanthoideae itself is thought to be

, many of the genera into which it has been divided (including ''Cheilanthes'', ''Doryopteris'', ''Notholaena'', and ''Pellaea'') have been shown to be

polyphyletic A polyphyletic group is an assemblage that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

Genera

The division of the subfamily Cheilanthoideae into genera and species remains uncertain . Christenhusz et al. (2011), the

Pteridophyte Phylogeny Group The Pteridophyte Phylogeny Group (PPG) is an informal international group of systematic botanists who collaborate to establish on the classification of pteridophytes ( lycophytes and ferns) that reflects knowledge about plant relationships discove ...

classification of 2016 (PPG I), and the November 2019 version of the ''Checklist of Ferns and Lycophytes of the World'' (''World Ferns'' 8.11) agree on the following genera: * '' Adiantopsis'' Fée * '' Aleuritopteris'' Fée * '' Argyrochosma'' (J.Sm.) Windham * '' Aspidotis'' (Nutt. ex Hooker) Copel. * '' Astrolepis'' D.M.Benham & Windham * '' Bommeria'' E.Fourn. * '' Calciphilopteris'' Yesilyurt & H.Schneid. * '' Cheilanthes'' Sw. (''nom. cons.'') * '' Cheiloplecton'' Fée * ''

Doryopteris ''Doryopteris'' is a genus of ferns in the subfamily Cheilanthoideae of the family Pteridaceae. Species The Circumscription (taxonomy), circumscription of the genus was uncertain . The ''Checklist of Ferns and Lycophytes of the World'' lists spe ...

'' J.Sm. (''nom. cons.'') * '' Gaga'' Pryer, F.W. Li & Windham * '' Hemionitis'' L. * '' Lytoneuron'' (Klotzsch) Yesilyurt * '' Mildella'' Trev. * '' Myriopteris'' Fée * ''

Notholaena ''Notholaena'' is a genus of ferns known as cloak ferns in the family Pteridaceae. Species of this genus are mostly epipetric (growing on rock) or occurring in coarse, gravelly soils, and are most abundant and diverse in the mountain ranges of wa ...

'' R.Br. * '' Ormopteris'' J.Sm. * '' Paragymnopteris'' K.H.Shing * '' Pellaea'' Link (''nom. cons.'') * '' Pentagramma'' Yatsk., Windham & E.Wollenw. * '' Trachypteris'' André ex Christ. Some other genera that have been included in the subfamily (or split off from genera included in the subfamily) are: * ''Allosorus'' Bernh. – not included by Christenhusz et al. (2011); accepted in PPG I; ''World Ferns'' 8.11 includes it in '' Aleuritopteris'', saying that it was wrongly typified * '' Baja'' Windham & L.O.George – accepted by ''World Ferns'' 8.11 * '' Mickelopteris'' Fraser-Jenk. – accepted by ''World Ferns'' 8.11 * '' Oeosporangium'' Vis. – included in ''Allosorus'' in PPG I; re-accepted by ''World Ferns'' 8.11 * ''Parahemionitis'' Panigrahi – accepted by Christenhusz et al. (2011) and PPG I; considered a synonym of '' Paragymnopteris'' by ''World Ferns'' 8.11, which places the species ''Parahemionitis cordata'' in the monotypic genus ''Mickelopteris'' * ''Pteridella'' Mett. ex Kuhn – accepted by Christenhusz & Chase (2014); considered a synonym of '' Pellaea'' by ''World Ferns'' 8.11 Other sources take a radically different approach. , ''

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

'' places all of the possible genera of the Cheilanthoideae in the single genus ''Hemionitis''. (''Parahemionitis'' is treated as a synonym of '' Acrostichum'', a member of a different subfamily.) While much work remains to be done in delineating monophyletic genera in the cheilanthoids (''Cheilanthes'', ''Doryopteris'' and ''Pellaea'' remaining notably polyphyletic), several major clades have been consistently recovered in phylogenetic analyses and given informal names, as shown here:

References

Pteridaceae Plant subfamilies {{Pteridaceae-stub