[Phylum] Chordata Bateson, 1885 - chordates
   Subphylum Craniata auct.
     Infraphylum Vertebrata Lamarck, 1801 - vertebrates
       Superclass †Osteostracomorphi
         Class †Osteostraci Lankester, 1868
           Order †Cephalaspidiformes Halstead Tarlo, 1967
             Suborder †Cephalaspidoidei Halstead Tarlo, 1967
               Family †Cephalaspididae Agassiz, 1844, nom. praeval.
                 Genus †Cephalaspis Agassiz, 1835