Phylum [Vertebrata] (Lamarck, 1801)
   Class Agnatha Cope, 1889
     Subclass †Cephalaspidomorphi Moy-Thomas & Mile, 1971 see Class Agnatha Cope, 1889
       Order †Osteostraci - osteostracans see Order Cephalaspidiformes
         1 Genus †Boreaspis Stensiö, 1927
         2 Genus †Dartmuthia Patten, 1931
         3 Genus †Hemicyclaspis Lankester, 1870
         4 Genus †Tremataspis Schmidt, 1866