†Placodermi McCoy, 1848
   †Arthrodira Woodward, 1891
     †Brachythoraci Gross, 1932
       †Eubrachythoraci Miles, 1971
         †Coccosteomorphi Stensiö, 1944
           1.1 Family †Camuropiscidae Dennis & Miles, 1979
           1.2 Genus †Harrytoombsia Miles & Dennis, 1979
           2 Family †Coccosteidae Traquair, 1888
           3 Family †Incisoscutidae Denison, 1984
           4 Family †Torosteidae Gardiner & Miles, 1990