[Phylum] [Arthropoda] Siebold, 1848 - arthropods
   Chelicerata Heymons, 1901
     Euchelicerata Weygoldt & Paulus, 1979
       [Order] †Eurypterida Burmeister, 1843 - eurypterids
         [Suborder] †Eurypterina Burmeister, 1843
           1 Superfamily †Onychopterelloidea Lamsdell, 2011 [monotypic]
           2 Superfamily †Moselopteroidea Lamsdell, Braddy & Tetlie, 2010 [monotypic]
           3 Superfamily †Megalograptoidea Caster & Kjellesvig-Waering, 1955 [monotypic]
           4 Superfamily †'Eurypteroidea' Burmeister, 1843 [monophyletic?]
           5 [Infraorder] †Diploperculata Lamsdell, Hoşgör & Selden, 2013