life see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Eukaryota Chatton, 1925 - eukaryotes see Domain Eukaryota Chatton, 1925
     Metazoa Haeckel 1874 - multicellular animals see Kingdom Animalia Linnaeus, 1758
       Bilateria Hatschek, 1888 - bilaterians see Subkingdom Bilateria Hatschek, 1888
         Nephrozoa Jondelius, Ruiz-Trillo, Baguñà & Riutort 2002
           Deuterostomia Grobben, 1908 - deuterostomes see Infrakingdom Deuterostomia Grobben, 1908
             Phylum Chordata Bateson, 1885 - chordates
               Subphylum Vertebrata Cuvier, 1812 - vertebrates see Infraphylum Vertebrata Lamarck, 1801
                 Class "Agnatha" Cope, 1889 [paraphyletic]
                   Subclass †Pteraspidomorphi Goodrich, 1909 see Class Pteraspidomorphi Goodrich, 1909
                     1 Order †Astraspida Berg, 1940 see Subclass Astraspida Berg, 1940
                     2 Order †Arandaspida see Subclass Arandaspida
                     3 Order †Heterostraci Lankester, 1868 - heterostracans see Subclass Heterostraci Lankester, 1868