Chelicerata Heymons, 1901
   Scorpiones Koch, 1837 - scorpions
     01 [plesion] Family †Proscorpiidae Scudder, 1885
     02 Suborder †Bilobosternina Kjellesvig-Waering, 1986
     03 †Holosternina Kjellesvig-Waering, 1986
     04 †Meristosternina Kjellesvig-Waering, 1986
     05 †Lobosternina Pocock, 1911
     06 Orthosternina Pocock, 1911 see Infraorder Orthosterni Pocock, 1911
     07 Genus †Brontoscorpio Kjellesvig-Waering, 1972, incertae sedis
     08 Genus †Eramoscorpius Waddington, Rudkin & Dunlop, 2015, incertae sedis
     09 Genus †Gondwanascorpio Gess, 2013, incertae sedis
     10 Genus †Gymnoscorpius Jeram, 1994, incertae sedis
     11 Genus †Hubeiscorpio Walossek, Li & Brauckmann, 1990, incertae sedis
     12 Genus †Liassoscorpionides Bode, 1951, incertae sedis
     13 Genus †Palaeomachus Pocock, 1911, incertae sedis
     14 Genus †Permomatveevia Dammann, 2017, incertae sedis
     15 Genus †Titanoscorpio Kjellesvig-Waering, 1986, incertae sedis
     16 Genus †Wattisonia Wills, 1960, incertae sedis