依据链束植物的化石记录,其首先出现的时期是泥盆纪早期。而到了三叠纪时,和一些现今的科有关的蕨类首次地出现了。“蕨类尖峰”则是出现在白垩纪晚期,当时有许多链束植物现今的科首先出现。
链束植物传统上是被归类在植物界的一门-蕨类植物门(Pteridophyta)里的,但因为蕨类植物是一个并系群而被现代的分类法拆分,并将链束植物单列为一个单系群。
传统上,有三个植物类群被认为是蕨类:两个厚囊蕨类-瓶尔小草科Ophioglossaceae(瓶尔小草属、阴地蕨属和蕨萁属)和合囊蕨科Marattiaceae,以及薄囊蕨类。合囊蕨科是赤道蕨类的主要类群,有着肥大的地下茎,且被认为是蕨类主要类群-薄囊蕨类的近亲。而还有其他一些的植物类群被认为是“拟蕨”:石松门里的石松、卷柏、水韭、松叶蕨科里的松叶蕨和木贼科里的木贼。但是,较现代的基因研究却显示,石松门和任何其他的维管植物之间都只是远远地关连着,是由维管植物分支的基底演化伸展出去的。而松叶蕨与木贼则和瓶尔小草跟合囊蕨一样是“真正的”蕨类。事实上,松叶蕨和瓶尔小草毫无疑问地是一个分支,而木贼跟合囊蕨则可以认为是另一个分支。
处理此一情形的一种可能方法是只将薄囊蕨类视为“真正的”蕨类,而将其他三个类群视为“拟蕨”。而在实际上,也已有数个分类法在规划着,并已有了少许的共识。2006年,Smith等人基于基因系统学研究提出了新的分类方法。2016年,广义蕨类植物系统发育组发表了PPG I的分类法,此一分类法将真蕨类视为纲级分类元,下辖4个亚纲[4]:
- 木贼植物亚纲 Equisetidae Warm.
- 瓶尔小草亚纲 Ophioglossidae Klinge
- 合囊蕨亚纲 Marattiidae Klinge
- 真蕨亚纲 Polypodiidae Cronquist, Takht. & W.Zimm.
真蕨亚纲包含着大多数主要被视为蕨类的植物。现今的研究支持以前基于形态学,将紫萁科认为是由薄囊蕨类演化史早期分支出来的一科;在某种意义上,这一科是介于厚囊蕨类和薄囊蕨类的中间位置上。下列的分类树参考自2016年PPG I的论文[4]:
本纲包括以下目:
- 目的地位未定的科:
- Botryopteridiaceae
- Cladoxylaceae
- Eviostachyaceae
- Hamatophytaceae
- Hyeniaceae
- Iridopteridaceae
- Kaplanopteridaceae
- Psalixochlaenaceae
- Pseudoborniaceae
- Rhacophytaceae
- Salvinaceae
- Sermayaceae
- Skaaripteridaceae
- Sorocaulaceae
- Sphenophyllaceae
- Stauropteridaceae
- Tedeleaceae
- Zygopteridaceae
- 目和科的地位未定的属:
- Acrangiophyllum Mamay, 1955
- Acrocarpus Schenk, 1867
- Actinostelopteris B.D.Sharma & D.R.Bohra, 1976
- Aculea J.G.Douglas, 1973
- Adelocladoxis T.Durieux, M.A.Lopez, A.W.Bronson & A.M.F.Tomescu, 2021
- Adiantophyllum M.Langeron, 1899
- Agasopteris Zalessky, 1937
- Alamatus J.G.Douglas, 1973
- Alsophilina Dormitzer, 1853
- Amanda J.G.Douglas, 1973
- Amdrupiopsis H.C.Sze & H.H.Lee, 1952
- Anapaulia C.M.Berry & D.Edwards, 1996
- Anastomopteris R.H.Wagner, 1958
- Andriania C.F.W.Braun, 1843
- Angariella V.A.Chachlov, 1939
- Aphlebia K.B.Presl, 1838
- Aphlebiocarpus Stur, 1877
- Aphlebiopteris Gothan & Zimmermann, 1932
- Aphyllostachys Göppert, 1865
- Arctopodium Unger, 1856
- Arthrodendromyelon O.Lignier, 1910
- Aspidostachys W.Remy, 1955
- Asterocalamitopsis W.Gothan, 1949
- Astralocaulis F.M.Hueber, 1971
- Aulacopteris Grand'Eury, 1877
- Baqueroties R.Herbst, 1967
- Bardia M.D.Zalessky, 1933
- Barsasopteris S.A.Stepanov, 1967
- Beinertia Göppert, 1836
- Berendtiopteris E.-M.Sadowski, L.J.Seyfullah & A.R.Schmidt, 2019
- Biarmella Zalessky, 1939
- Bifariusotheca X.H.Zhao ex A.B.Doweld, 2019
- Blechnoxylon Etheridge, 1899
- Bockschia Göppert, 1836
- Boiophyton J.Obrhel, 1959
- Bonaventurea Debey & Ettingshausen, 1859
- Borovuchkia M.D.Parfenova, 1965
- Boweria Kidston, 1911
- Calamariophyllum M.Hirmer, 1927
- Calamodendrostachys B.Renault, 1890
- Calamophyllite F.C.Grand'Eury ex A.T.Brongniart, 1872
- Calamorrhiza Grand'Eury, 1877
- Callipteridium C.E.Weiss, 1870
- Carolopteris Debey & Ettingshausen, 1859
- Ceratophyllites Unger, 1845
- Chacassopteris G.P.Radczenko, 1960
- Chansitheca Regè, 1921
- Cheilanthites H.R.Göppert, 1836
- Cheiloleptites G.Saporta, 1861
- Chelepteris Corda, 1845
- Chlamidostachys White, 1937
- Chrysodiopteris Saporta
- Climaciophyton G.Steinmann, 1929
- Copiapaea H.Graf zu Solms-Laubach, 1899
- Crucistachys T.Nakai, 1943
- Cryptogrammites G.Andreánszky, 1951
- Cuyenopteris E.I.Vera, 2010
- Cymoglossa W.P.Schimper, 1869
- Cyphopteris K.B.Presl, 1838
- Dactylopteris Göppert, 1852
- Dalejophyton J.Obrhel, 1957
- Delgadoa O.Heer, 1881
- Dendraena Nemejc, 1934
- Denglongia J.-H.Xue & S.-G.Hao, 2008
- Dichoneuron G.Saporta, 1878
- Dichopteris Zigno, 1864
- Dicropteris Pomel, 1849
- Dictyocalamites E.A.N.Arber, 1912
- Dictyodendron Landsborough, 1844
- Diplasterotheca Hirmer, 1927
- Diplazites H.R.Göppert, 1836
- Diplodictyum C.F.W.Braun, 1843
- Diplophacelus Corda, 1845
- Dipteriphyllum F.Krasser, 1896
- Discosoropteris J.Pšenicka et al., 2022
- Doleropteris Grand'Eury, 1877
- Duisbergia R.Kräusel & H.Weyland, 1929
- Dyotheca W.Hartung, 1938
- Echinosporangites J.Pšenicka & J.Bek, 2009
- Ellesmeris S.A.Hill, S.E.Scheckler & J.F.Basinger, 1997
- Endocalamites Grand'Eury, 1877
- Endoxylon D.H.Scott, 1924
- Enigmophyton O.A.Høeg, 1942
- Eospermatopteris Goldring, 1924
- Equisetina Zalessky, 1939
- Eupalaeostachya T.A.Istchenko, 1965
- Eusphenopteris R.Kidston, 1882
- Filicosorus O.P.Suthar, D.R.Bohra & B.D.Sharma, 1995
- Flicheia F.Pelourde, 1908
- Foozia P.Gerrienne, 1992
- Fortisia Visiani, 1858
- Fortopteris M.Boersma, 1969
- Fremouwa M.A.Millay & T.N.Taylor, 1990
- Fuellingia H.-J.Schweitzer, 2002
- Furcillopteris I.M.Miller & L.J.Hickey, 2008
- Gagariostrobus N.K.Mogutcheva, 1987
- Gellera Hollick, 1931
- Ginkgophyllum Saporta, 1875
- Glossochlamys Ettingshausen & Gardner, 1879
- Gondwanophyton P.K.Maithy, 1974
- Goniopterites A.T.Brongniart, 1849
- Gordonopteris J.H.A.van Konijnenburg-van Cittert, E.Kustatscher & M.Wachtler, 2006
- Graminites H.B.Geinitz, 1865
- Grammatocaulis W.D.Tidwell & A.C.Rozefelds, 1990
- Grandeurya R.Zeiller, 1883
- Guptiorachis B.D.Sharma, 1971
- Gyrophyllites Glocker, 1841
- Gyropteris A.J.Corda, 1845
- Hapalopteris D.R.J.Stur, 1883
- Haplotheca W.Gothan & W.Hartung ex W.Gothan, 1949
- Hawlea Corda, 1845
- Heterofilicites E.W.Berry, 1905
- Hierogramma Unger, 1856
- Hippurites Lindley & W.Hutton, 1834
- Hissaropteris Y.M.Kuzichkina & T.A.Sixtel, 1960
- Honseleria H.Mustafa, 1978
- Hymenophyllea C.E.Weiss, 1869
- Hyphopteris W.P.Schimper, 1869
- Jacutopteris N.D.Vasilevskaja, 1960
- Kaloxylon Williamson, 1875
- Kamatheca A.B.Doweld, 2019
- Kenderlykia A.I.Turutanova-Ketova, 1962
- Keraphyton A.Champreux, B.Meyer-Berthaud & A.-L.Decombeix, 2020
- Kirchneria C.F.W.Braun, 1854
- Koinostachys W.Remy, 1955
- Korallipteris E.I.Vera & M.G.Passalia, 2012
- Kryshtofovichia P.A.Nikitin, 1934
- Langoxylon F.Stockmans, 1968
- Laskovskia Zalessky, 1939
- Lenlogia V.A.Krassilov & T.V.Zakharova, 1995
- Lepidocalamus G.F.Matthew, 1906
- Lescuropteris W.P.Schimper, 1869
- Liknopetalon S.J.Smithies, 1985
- Litostrobus Mamay, 1954
- Lontzenia Stockmans & Willière, 1952
- Lorophyton M.Fairon-Demaret & C.S.Li, 1993
- Loxopteris Pomel, 1846
- Macrostachya W.P.Schimper, 1869
- Manebachia R.Remy & W.Remy, 1958
- Maokheopteris I.N.Srebrodol'skaja, 1969
- Marattites Marion & Laurent, 1898
- Marginopteris W.Gothan, 1941
- Mattenoxylon A.L.Jurina, 1988
- Medwellia N.S.Nagalingum & S.McLoughlin, 2002
- Megalorhachis Unger, 1856
- Merianopteris O.Heer, 1877
- Mesocrossotheca S.V.Naugolnykh & N.K.Mogutcheva, 2001
- Mesoneuraster F.Sandberger, 1867
- Microzygia Read, 1936
- Mikasapteris H.Nishida, R.A.Stockey, Y.Takebe, J.Legrand & T.Yamada, 2022
- Mittagia O.Lignier, 1913
- Mointina M.A.Senkevitsch, 1961
- Mokrawia G.Knopp, 1933
- Monheimia Debey & Ettingshausen, 1859
- Monoscalitheca M.L.Abbott, 1961
- Multifurcatus Y.Wang, 2003
- Nephropteris A.T.Brongniart, 1849
- Neriopteris Newberry, 1873
- Noeopteris Janssen, 1940
- Nymbotheca W.B.K.Holmes, 2000
- Ochotopteris E.L.Lebedev, 1974
- Oligosporangiopteris J.Votocková Frojdová, J.Wang, J.Pšenicka, J.Bek, S.Opluštil & M.Libertín, 2021
- Osmundophyllum Velenovský, 1889
- Otidophyton D.White, 1905
- Ovopteridium F.Behrend, 1909
- Pachwarophyllum B.Prasad & P.K.Maithy, 1990
- Padgettia S.H.Mamay, 1962
- Palmatopteris H.Potonié, 1893
- Panxia Y.Wang & C.M.Berry, 2006
- Parapecopteris Grand'Eury, 1890
- Parasphenophyllum K.Asama, 1970
- Paratrizygia K.Asama, 1970
- Peltastrobus Baxter, 1950
- Peremopteris Zalessky, 1937
- Phialopteris K.B.Presl, 1838
- Phillipopteris J.J.Hamer & G.W.Rothwell, 1983
- Pietzschia Gothan, 1927
- Plumatopteris Kidston, 1894
- Polypetalophyton B.Geng, 2003
- Polypodites H.R.Göppert, 1836
- Polytheca H.Potonié, 1900
- Polyxylon C.B.Read & Campbell, 1939
- Prosseria C.B.Read, 1953
- Protocalamites J.P.Lotsy, 1909
- Protopteridophyton C.-S.Li & J.Hsü, 1987
- Protopteris Sternberg ex K.B.Presl, 1838
- Prynadaia T.A.Sixtel, 1956
- Psammopteris C.E.I.von Eichwald, 1862
- Pseudomariopteris P.Danzé-Corsin, 1953
- Pseudophyllotheca A.I.Turutanova-Ketova, 1968
- Pteridites Tuzson, 1913
- Pteridoleimma Debey & Ettingshausen, 1859
- Pteridorachis Nathorst, 1902
- Pteridotheca D.H.Scott, 1907
- Pterisorus G.W.Rothwell & R.A.Stockey, 2006
- Pterygopteris Johansson, 1922
- Ptilorhachis Corda, 1845
- Rachiopteris W.C.Williamson ex A.C.Seward, 1894
- Raphaelia Debey & Ettingshausen, 1859
- Resilitheca D.Edwards, U.Fanning, K.L.Davies, L.Axe & J.B.Richardson, 1995
- Rhipidophyton C.M.Berry & Y.Wang, 2006
- Rhizomopsis W.Gothan & H.C.Sze, 1933
- Rhymokalon S.E.Scheckler, 1975
- Rienitsia A.B.Walkom, 1932
- Rotafolia D.-M.Wang, S.-G.Hao & Q.Wang, 2005
- Rotoxylon J.Cordi & W.E.Stein, 2005
- Saarotheca W.Remy, 1953
- Saccopteris D.R.J.Stur, 1883
- Sacheria Ettingshausen, 1852
- Sachyogyrus Zalessky, 1939
- Santhalea P.K.Maithy, 1977
- Sarcopteris B.Renault, 1883
- Sarituma M.A.Senkevitsch, 1963
- Saropteris E.F.Tschirkova, 1937
- Scaphidopteris B.Renault, 1883
- Schizopteris A.T.Brongniart, 1828
- Sciadipteris Sternberg ex K.B.Presl, 1838
- Sectilopteris I.M.Miller & L.J.Hickey, 2008
- Selenopteris Corda, 1845
- Semigleicheniidites Nagy, 1968
- Sentistrobus S.D.Riggs & G.W.Rothwell, 1985
- Shirakia S.Kawasaki, 1934
- Silesiopteris O.Posthumus, 1924
- Solenostelopteris Kershaw, 1910
- Sorotheca D.R.J.Stur, 1883
- Sphaciinodum J.M.Osborn & T.N.Taylor, 1989
- Sphalmopteris Corda, 1845
- Sphegopteris Zalessky, 1939
- Sphenasterophyllites J.T.Sterzel, 1907
- Sphenostrobus E.D.Levittan & E.S.Barghoorn, 1948
- Sphondylophyton R.E.Schultes & E.Dorf, 1938
- Sphyropteris D.R.J.Stur, 1883
- Staphylopteris K.B.Presl, 1838
- Steffensia Göppert, 1836
- Stephanida F.J.A.N.Unger, 1856
- Stephanofilix Post & O.Kuntze, 1903
- Stephanophyllites J.H.Millan & E.Dolianiti, 1980
- Stichopteris H.B.Geinitz, 1858
- Stockmansia B.Bohlin, 1976
- Straelenipteris Stockmans, 1936
- Stramineopteris S.A.Little, R.A.Stockey & G.W.Rothwell, 2006
- Sturia Nemejc, 1934
- Sulcocladus F.Stockmans, 1968
- Surangea S.D.Chitaley & M.T.Sheikh, 1972
- Suvundukia M.D.Zalessky, 1948
- Sylvopteris Zalessky, 1937
- Syncardia Unger, 1856
- Szecalamitina A.B.Doweld, 2012
- Taenitites P.H.Fritel, 1909
- Taphrocanna C.E.I.von Eichwald, 1852
- Teilhardia Seward, 1913
- Tetrameridium W.Gothan, 1913
- Tetraptilon Frenguelli, 1950
- Tetratmema P.Corsin, 1951
- Thainguyenopteris I.N.Srebrodol'skaja, 1969
- Tomiella V.A.Chachlov, 1939
- Tortkophyton A.L.Jurina, 1969
- Trochophyllum H.C.Wood, 1861
- Tumniella A.G.Lebedeva, 1940
- Vachramelia L.B.Golovneva & V.A.Krassilov, 2001
- Voelkelia Solms-Laubach, 1896
- Wattieza F.Stockmans, 1968
- Woodwardites H.R.Göppert, 1836
- Zalesskyella E.F.Tschirkova ex M.D.Zalessky, 1939
- Zonopteris Debey & Ettingshausen, 1859