[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   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
         Deuterostomia Grobben, 1908 - deuterostomes see Infrakingdom Deuterostomia Grobben, 1908
           Phylum Chordata Bateson, 1885 - chordates
             Subphylum Vertebrata Cuvier, 1812 - vertebrates
               Infraphylum Gnathostomata Gegenbaur, 1874 - jawed vertebrates see Superclass Gnathostomata Gegenbaur, 1874
                 Class Chondrichthyes Huxley, 1880 - cartilaginous fishes
                   Subclass Elasmobranchii Bonaparte, 1838 - shark-like fishes
                     1 Infraclass †unnamed
                     2 Order †Eugeneodontiformes Zangerl, 1981
                     3 Order †Petalodontiformes Zangerl, 1981
                     4 Infraclass Euselachii Hay, 1902 - sharks and rays, and related fossils