[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Appendiculata {Lankester}
         Branch Gnathopoda Straus-Durkheim, 1829
           Grade Condylopoda
             Class Crustacea Brünnich, 1772 - crustaceans see Superclass Crustacea Pennant, 1777
               Grade Malacostraca Latreille, 1802
                 Branch Thoracostraca
                   Order Decapoda Latreille, 1802 - decapods
                     1 Genus Astacus Fabricius, 1775
                     2 Genus Pagurus Fabricius, 1775