''Trichomanes'' is a genus of

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 ...

s in the family

Hymenophyllaceae The Hymenophyllaceae, the filmy ferns and bristle ferns, are a family of two to nine genera (depending on classification system) and about 650 known species of ferns, with a subcosmopolitan distribution, but generally restricted to very damp pla ...

, termed bristle ferns. The

circumscription Circumscription may refer to: * Circumscribed circle * Circumscription (logic) *Circumscription (taxonomy) * Circumscription theory, a theory about the origins of the political state in the history of human evolution proposed by the American anthr ...

of the genus is disputed. All ferns in the genus are filmy ferns, with leaf tissue typically 2 cells thick. This thinness generally necessitates a permanently humid habitat, and makes the fronds somewhat translucent. Because of this membrane-like frond tissue, the plant is prone to drying out. “Filmy ferns” in the taxa Hymenophyllaceae grow in constantly wet environments. Many are found in cloud forests such as “Choco” in Colombia. There are also members of the taxa that can grow submersed in water. The name bristle fern refers to the small bristle that protrudes from the indusia of these ferns.

Taxonomy

The genus ''Trichomanes'' was first described by

Carl Linnaeus Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...

in 1753. Its status, like other genera in the subfamily Trichomanoideae, remains disputed. 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) accepts the genus as one of eight in the subfamily Trichomanoideae, saying that there are about 60 species. , the ''Checklist of Ferns and Lycophytes of the World'' listed about 70 species. Other sources, including ''

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 ...

'' , treated ''Trichomanes'' as the only genus in the subfamily Trichomanoideae, so that it included all the other genera, and had about 250 species.

Phylogeny

Species formerly placed in this genus include: * ''Trichomanes angustatum'' Carmich. = '' Polyphlebium angustatum'' (Carmich.) Ebihara & Dubuisson * ''Trichomanes bauerianum'' = ''

Callistopteris baueriana ''Callistopteris bauerianum'', known as the large filmy fern and Bauer's bristle fern, is a fern in the family Hymenophyllaceae. The specific epithet honours the Austrian botanical artist, Frederick Lucas Bauer (1760–1826), who collected plan ...

'' (Endl.) Copel – Bauer's bristle fern * ''Trichomanes boryanum'' = ''

Cephalomanes atrovirens ''Cephalomanes atrovirens'' is a species of fern in the family Hymenophyllaceae. The genus '' Cephalomanes'' is accepted in the Pteridophyte Phylogeny Group classification of 2016 (PPG I), but not by some other sources. , ''Plants of the World On ...

'' * ''Trichomanes boschianum'' = ''

Vandenboschia boschiana ''Vandenboschia boschiana'', synonym ''Trichomanes boschianum'', also known as the Appalachian bristle fern or Appalachian filmy fern, is a small delicate perennial leptosporangiate fern which forms colonies with long, black creeping rhizomes. ...

'' (J.W.Sturm ex Bosch) Ebihara & K.Iwats. – Appalachian bristle fern * ''Trichomanes caudatum'' Brack. = '' Abrodictyum caudatum'' (Brack.) Ebihara & K.Iwats. * ''Trichomanes intricatum'' = '' Crepidomanes intricatum'' (Farrar) Ebihara & Weakley – Weft fern * ''Trichomanes melanopus'' = '' Didymoglossum melanopus'' (Baker) Copel. * ''Trichomanes petersii'' = ''

Didymoglossum petersii ''Didymoglossum petersii'', the dwarf bristle fern, is a species in the family Hymenophyllaceae, (filmy ferns). It is one of three filmy ferns native to a significant area of the United States. It is found only in the nine most southeastern state ...

'' (A. Gray) Copel. – Dwarf bristle fern * ''Trichomanes reniforme'' = ''

Hymenophyllum nephrophyllum ''Hymenophyllum nephrophyllum'', commonly known as the kidney fern, is a filmy fern species native to New Zealand. It commonly grows on the forest floor of open native bush. Individual kidney-shaped fronds stand about 5–10 cm tall. In hot ...

'' Ebihara & K. Iwats. * ''Trichomanes speciosum'' = ''

Vandenboschia speciosa ''Vandenboschia speciosa'', synonym ''Trichomanes speciosum'', commonly known as the Killarney fern, is a species of fern found widely in Western Europe. It is most abundant in Ireland, Great Britain, Brittany, Galicia, Canary Islands, Madeira ...

'' (Willd.) G. Kunkel * ''Trichomanes tenuissimum'' = '' Polyphlebium tenuissimum'' (Bosch) ''comb. ined.'' * ''Trichomanes venosum'' R.Br. = '' Polyphlebium venosum'' (R.Br.) Copel.

References

{{Polypodiidae-stub Hymenophyllales Fern genera Taxonomy articles created by Polbot Long stubs with short prose