[Phylum] [Arthropoda] Siebold, 1848 - arthropods
   Chelicerata Heymons, 1901
     Euchelicerata Weygoldt & Paulus, 1979
       [Order] Scorpiones Koch, 1837 - scorpions
         Suborder Neoscorpionina Thorell & Lindström, 1885
           Infraorder Orthosterni Pocock, 1911
             Parvorder Iurida Soleglad & Fet, 2003
               Superfamily Scorpionioidea Dunlop, Penney & Jekel, 2010, orth. inval. see Superfamily Scorpionoidea Latreille, 1802
                 Family Hemiscorpiidae Pocock, 1893
                   1 Genus †Cretaceoushorniops Dunlop, Penney & Jekel, 2023, orth. inval. see Genus Cretaceoushormiops Lourenço, 2018
                   2 Genus †Cretaceousopisthacanthus Lourenço, 2021
                   3 Genus †Protoischnurus Carvalho & Lourenço, 2001