[Kingdom] Animalia Linnaeus, 1758 - animals
   Grade Enterozoa
     Grade Cœlomata
       Phylum Vertebrata Lamarck, 1801 see Infraphylum Vertebrata Lamarck, 1801
         Branch Craniata Linnaeus, 1758
           Grade Gnathostoma
             Subgrade Heterodactyla branchiata
               Class Pisces Linnaeus, 1758 see Superclass Pisces Linnaeus, 1758
                 Subclass Teleostei Müller, 1845 see Division Teleostei Müller, 1845
                   Branch Physostomi
                     Order Abdominales Linnaeus, 1758
                       Genus Esox Linnaeus, 1758