From Kazlev, 2000, and Tollerton, 1989

Traditional taxonomy of Eurypterida

Alternative taxonomy after Tollerton, 1989

<==o †Eurypterida Burmeister, 1843 [Gigantostraca Haeckel, 1866; Cyrtoctenida Størmer & Waterston, 1968] (meriskorpionit; seascorpions)
   |--o †Stylonuroidea Diener, 1924 [Stylonauracea Diener, 1924; Drepanopteroidea Kjellesvig-Waering, 1966]
   |  |--o †Stylonuridae Diener, 1924 [Pageidae Kjellesvig-Waering, 1966, in Waterston, 1979]
   |  |  |--o †Stylonurus Page, 1856
   |  |  |  |-- †S. powriei Page, 1856
   |  |  |  |-- †S. dolichopteroides Størmer,
   |  |  |  |-- †S. logani Woodward,
   |  |  |  `-- †S. macrophthalmus Laurie
   |  |  |-- †Stylonurella Kjellesvig-Waering, 1966
   |  |  |-- †Kiaeropterus Waterston, 1979
   |  |  |-- †Tarsopterella scoticus (Woodward, 1864) Størmer, 1951 [pro Tarsopterus Clarke & Ruedemann, 1912 (non Reinhardt & Luetken, 1862); Stylonurus scoticus Woodward, 1864] [incl.? Erieopterus brewsteri (Woodward, 1864) (juveline)]
   |  |  |-- †Melbournopterus crossotus Caster & Kjellesvig-Waering, 1953
   |  |  `--o †Campulocephalus Eichw., 1860 
   |  |     |-- †C. oculatus (Kutorga, 1852) [Limulus oculatus Kutorga, 1852; Eidothea Scouler, 1831 (non Risso, 1826; nec Chambers, 1873]
   |  |     `-- †C. scouleri (Hibbert)
   |  |--o †Drepanopteridae Kjellesvig-Waering 1966
   |  |  |-- †Alkenopterus Størmer, 1974
   |  |  |-- †Moselopterus Størmer, 1974
   |  |  `--o †Drepanopterus Laurie, 1892
   |  |     |-- †D. abonensis Simpson, 1951
   |  |     |-- †D. struvei StÝrmer, 1976
   |  |     |-- †D. pentlandicus Laurie, 1892
   |  |     `-- †D. longicaudatus Clarke & Ruedemann
   |  |?-o †Parastylonuridae Waterston, 1979
   |  |  |?- ?†Stylonuroides Kjellesvig-Waering, 1966
   |  |  |?-o ?†Brachyopterus Størmer, 1951
   |  |  |  |-- †B. stubblefieldi Størmer, 1951
   |  |  |  `-- †B. pentagonalis (Størmer)
   |  |  `-- †Parastylonurus Kjellesvig-Waering, 1966
   |  |--o †Laurieipteridae Kjellesvig-Waering, 1966
   |  |  |-- †Laurieipterus Kjellesvig-Waering, 1966
   |  |  |--o †Ctenopterus Clark & Ruedemann, 1912
   |  |  |  |-- †C. cestrotus (Clarke, 1907) [Eurypterus cestrotus Clarke, 1907; = ?Dolichocephala Claypole, 1883 (non MacQuart, 1823)]
   |  |  |  `-- †C.? lacoana (Claypole)
   |  |  |-- †Hallipterus Kjellesvig-Waering, 1963a
   |  |  |-- †Pagea Waterston, 1962
   |  |  `?- ?†Mazonipterus Kjellesvig-Waering, 1963b
   |  |--o †Dolichopteridae Kjellesvig-Waering & Størmer, 1952
   |  |  |-- †Dolichopterus macrocheirus Hall, 1859 [Eurypterus (Dolichopterus) macrocheirus Hall, 1859]
   |  |  |-- †Strobilopterus princetoni Ruedemann, 1935
   |  |  |-- †Ruedemannipterus Kjellesvig-Waering, 1966
   |  |  `-- †Syntomopterus Kjellesvig-Waering, 1961a
   |  |--o †Kokomopteroidea Kjellesvig-Waering, 1966 [nom. trans. Tollerton, 1989]
   |  |  |--o †Kokomopteridae Kjellesvig-Waering, 1966
   |  |  |  |--o †Kokomopterus Kjellesvig-Waering, 1966
   |  |  |  |  `-- †K. longicaudatus (Clarke & Ruedemann, 1912)
   |  |  |  `-- †Lamontopterus Waterston, 1979
   |  |  `--o †Hardieopteridae Tollerton, 1989
   |  |     `-- †Hardieopterus Waterston, 1979
   |  |--o †Brachyopterelloidea Tollerton, 1989
   |  |  `--o †Brachyopterellidae Tollerton, 1989
   |  |     `-- †Brachypterella Kjellesvig-Waering, 1966
   |  |--o †Rhenopteroidea Størmer, 1951
   |  |  `--o †Rhenopteridae Størmer, 1951
   |  |     `-- †Rhenopterus diensti Størmer, 1936
   |  `--o †Mycteropoidea Cope, 1886
   |     |--o †Mycteropidae Cope, 1886
   |     |  `--o †Mycterops Cope, 1886 [Glaucodes Pruvost, 1923]
   |     |     |-- †M. scabrosus (Woodward, H.)
   |     |     `-- †M. mathieui (Pruvost, 1923) [Glaucodes mathieui Pruvost, 1923]
   |     `--o †Woodwardopteridae Kjellesvig-Waering, 1959
   |        |-- †Woodwardopterus Kjellesvig-Waering, 1959
   |        `-- †Vernopterus Waterson, 1968
   `--o †Eurypteroidea Burmeister, 1843 [Eurypteracea Burmeister, 1843]
      |--o †Eurypteridae Burmeister, 1843
      |  |--o †Eurypterus De Kay, 1825 [non Mabille, 1877; nec Sharpe, 1896] [incl. Baltoeurypterus Størmer, 1973 sensu Tetlie, 2006]
      |  |  |-- †E. minor Laurie, 1898
      |  |  |-- †E. remipes
      |  |  |-- †E. pittsfordensis
      |  |  |-- †E. fischeri Eichw.
      |  |  |-- †E. hankeni Tetlie, 2006
      |  |  |-- †E. leopoldi Tetlie, 2006
      |  |  |-- †E. tetragonophthalmus (Fischer, 1839) [Baltoeurypterus tetragonophthalmus]
      |  |  |-- †E. latus [Baltoeurypterus latus]
      |  |  `-- †E. remipes [Baltoeurypterus remipes]
      |  `-- †Tylopterella boyli (Whiteaves, 1884) Størmer, 1951 [pro Tylopterus Clarke & Ruedemann, 1912 (non Capiomont, 1868; nec Leconte, 1876); Eurypterus boyli Whiteaves, 1884]
      |--o †Erieopteridae Tollerton, 1989
      |  |--o †Buffalopterus Kjellesvig-Waering & Heubusch, 1962
      |  |  `-- †B. pustulosus [Erieopterus pustulosus]
      |  |--o †Onychopterella Størmer, 1951 [pro Onychopterus Clarke & Ruedemann, 1912 (non Reichenbach, 1850)]
      |  |  `-- †O. kokomoensis (Miller & Gurley, 1896) [Eurypterus kokomoensis Miller & Gurley, 1896]
      |  `--o †Erieopterus Kjellesvig-Waering, 1958
      |     |--o †E. microphthalmus (Hall, 1859)
      |     |  |-- †E. m. microphthalmus (Hall, 1859)
      |     |  |-- †E. m. eriensis (Whitfield, 1882)
      |     |  `-- †E. m. turgidus Stumm & Kjellesvig-Waering, 1962
      |     |-- †E. laticeps (Schmidt, 1883)
      |     |-- †E. chadwicki (Clarke & Ruedemann, 1912)
      |     `-- †E. hudsonicus (Ruedemann, 1934)
      `--+--o †Adelophthalmidae Tollerton, 1989
         |  |-- Adelophthalmus imhofi (Jordan & Meyer, 1856) Jordan & Meyer, 1854 [=? Lepidoderma imhofi (Jordan & Meyer, 1856) Reuss, 1855]
         |  |-- †Bassipterus Kjellesvig-Waering & Leutze, 1966
         |  `-- †Unionopterus Chernyshev, 1948
         `--+--+--o †Slimonioidea Novojilov, 1962
            |  |  `--o Slimoniidae Novojilov, 1962
            |  |     |-- †Slimonia acuminatus (Salter, 1856) Page, 1856 [Himantopterus acuminata Salter, 1856]
            |  |     `-- †Salteropterus abbreviatus (Salter, 1859) Kjellesvig-Waering, 1951 [Eurypterus abbreviatus Salter, 1859]
            |  `--o †Pterygotoidea Clarke & Ruedemann, 1912 [Pterygotina Caster & Kjellesvig-Waering, 1964]
            |     |--o †Jaekelopteridae Størmer, 1974
            |     |  `-- †Jaekelopterus Waterston, 1964
            |     `--o †Pterygotidae Clarke & Ruedemann, 1912
            |        |-- †Truncatiramus Kjellesvig-Waering, 1961b
            |        `--o †Pterygotus Agassiz, 1839
            |           |--o †(Pterygotus) Agassiz, 1839 [= Curviramus Ruedemann, 1935]
            |           |  |-- †P. (P.) rhenaniae Jaekel
            |           |  `-- †P. (P.) anglicus Agassiz
            |           |--o †(Acutiramus) Ruedemann, 1935
            |           |  |-- †P. (A.) buffaloensis Pohlman, 1881
            |           |  `-- †P. (A.) bohemicus (Barrande)
            |           `--o †(Erettopterus) Salter, 1859 [pro Himantopterus Salter, 1856 (non Westmail, 1836)]
            |              |-- †P. (P.) bilobus (Salter, 1856?)
            |              `-- †P. (P.) osiliensis Schmidt
            `--+-- †Hughmillerioidea Kjellesvig-Waering, 1951 [nom. trans. Størmer, 1974]
               `--+--o †Mixopteroidea Caster & Kjellesvig-Waering, 1955
                  |  |--o †Mixopteridae Caster & Kjellesvig-Waering, 1955)
                  |  |  `--o †Mixopterus Ruedemann, 1921
                  |  |     |-- †M. multispinosus (Clarke & Ruedemann, 1912) [Stylonurus (Ctenopterus) multispinosus Clarke & Ruedemann, 1912]
                  |  |     `-- †M. kiaeri Størmer,
                  |  `--o †Lanarkopteridae Tollerton, 1989
                  |     `--o †Lanarkopterus Ritchie, 1968
                  |        `-- †L. dolichoschelus (Størmer)
                  `--o †Megalograptoidea Caster & Kjellesvig-Waering, 1955 [nom. trans. Tollerton, 1989]
                     `--o †Megalograptidae Caster & Kjellesvig-Waering, 1955
                        |-- †Echinognathus clevelandi (Walcott, 1882) Walcott, 1882 [Eurypterus clevelandi Walcott, 1882]
                        `--o †Megalograptus Miller, 1874
                           |-- †M. welchi Miller, 1874
                           `-- †M. ohioensis Caster & Kjellesvig-Waering,

Eurypterida incertae sedis:

AngustidontusDorfopterus Kjellesvig-Waering, 1955
    †Pittsfordipterus Kjellesvig-Waering & Leutze, 1966
    †Willwerathia Størmer, 1969
    †Glyptoscorpius perornatus Peach, 1882
    †Belinuropsis wigodensis Matthew, 1909

Reference(s):