Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Arthropoda Siebold, 1848 - arthropods
     Subphylum Crustacea Brünnich, 1772 - crustaceans see Superclass Crustacea Pennant, 1777
       Class Malacostraca Latreille, 1802
         Subclass Eumalacostraca Grobben, 1892
           Superorder Eucarida Calman, 1904
             Order Decapoda Latreille, 1802 - decapods
               Suborder Pleocyemata Burkenroad, 1963
                 Infraorder Brachyura Latreille, 1802 - true crabs
                   Genus Callinectes Stimpson, 1860
                   Genus Cancer Linnaeus, 1758 - cancer crab
                   Genus Cardisoma Latreille, 1824
                   Genus Corystes Bosc, 1802
                   Family Grapsidae MacLeay, 1838
                   Genus Grapsus Lamarck, 1801
                   Genus Hemigrapsus Dana, 1851
                   Genus Macrocheira de Haan, 1839
                   Genus Maja Lamarck, 1801
                   Genus Ocypode Weber, 1795
                   Genus Pachygrapsus Randall, 1840
                   Genus Pinnotheres Latreille, 1802
                   Family Portunidae Rafinesque, 1815
                   Genus Portunus Weber, 1795
                   Genus Xantho Leach, 1815