[Phylum] [Arthropoda] Siebold, 1848 - arthropods
   Chelicerata Heymons, 1901
     Euchelicerata Weygoldt & Paulus, 1979
       [Order] †Eurypterida Burmeister, 1843 - eurypterids
         [Suborder] †Eurypterina Burmeister, 1843
           [Infraorder] †Diploperculata Lamsdell, Hoşgör & Selden, 2013
             1 Superfamily †Carcinosomatoidea Størmer, 1934
             2 Superfamily †"Waeringopteroidea" nom. ined.
             3 Superfamily †Adelophthalmoidea Tollerton, 1989 [monotypic]
             4 Superfamily †Pterygotioidea Dunlop, Penney & Jekel, 2010, orth. inval. see Superfamily Pterygotoidea Clarke & Ruedemann, 1912