[Phylum] Chordata Bateson, 1885 - chordates
   Subphylum Craniata auct.
     Infraphylum Vertebrata Lamarck, 1801 - vertebrates
       Superclass †Osteostracomorphi
         Class †Osteostraci Lankester, 1868
           Order †Thyestiformes
             1 Family †Procephalaspididae Stensiö, 1958
             2 Family †Thyestidae Rohon, 1892
             3 Family †Witaaspididae Afanassieva, 1991
             4 Family †Tremataspididae Woodward, 1891, nom. praeval.
             5 Family †Kiaeraspididae Stensiö, 1932, nom. praeval.