[Phylum] [Arthropoda] Siebold, 1848 - arthropods
   Chelicerata Heymons, 1901
     Euchelicerata Weygoldt & Paulus, 1979
       [Order] Pseudoscorpiones De Geer, 1778
         [Suborder] Heterosyphronida Dunlop, Penney & Jekel, 2020, orth. inval. see Suborder Heterosphyronida Chamberlin, 1929
           Superfamily Chthonoidea Dunlop, Penney & Jekel, 2010, orth. inval. see Superfamily Chthonioidea Daday, 1889
             Family Chthoniidae Daday, 1889
               1 Genus †Chelignathus Menge, 1854
               2 Genus Chthonius Koch, 1843
               3 Genus Lechytia Balzan, 1892
               4 Genus Paraliochthonius Beier, 1956
               5 Genus †Prionochthonius Wriedt, Harvey, Hammel, Kotthoff & Harms, 2021
               6 Genus Pseudochthonius Balzan, 1892
               7 Genus Tyrannchthonius Dunlop, Penney & Jekel, 2011, orth. inval. see Genus Tyrannochthonius Chamberlin, 1929
               8 Genus †Weygoldtiella Harvey, Cosgrove, Harms, Selden, Shih & Wang, 2018