[Phylum] Chordata Bateson, 1885 - chordates
   Subphylum Craniata auct.
     Infraphylum Vertebrata Lamarck, 1801 - vertebrates
       Superclass †Osteostracomorphi
         Class †Osteostraci Lankester, 1868
           Order †Cephalaspidiformes Halstead Tarlo, 1967
             1 Suborder †Ateleaspidoidei
             2 Suborder †Cephalaspidoidei Halstead Tarlo, 1967
             3 Suborder †Scolenaspidoidei Afanassieva, 1991