[Phylum] Chordata Bateson, 1885 - chordates
   Subphylum Craniata auct.
     Infraphylum Vertebrata Lamarck, 1801 - vertebrates
       Superclass Gnathostomata Gegenbaur, 1874 - jawed vertebrates
         Class †Placodermi McCoy, 1848
           Order †Acanthothoraci Stensiö, 1944
             1 Family †Radotinidae Arambourg, 1958
             2 Family †Kolymaspididae Bystrow, 1956, nom. praeval.
             3 Family †Palaeacanthaspidae Stensiö, 1944
             4 Family †Hagiangellidae Dupret, Phuong, Thanh, Phong, Janvier & Clément, 2011