vertebrates Lamarck, 1801 - vertebrates see Infraphylum Vertebrata Lamarck, 1801
   Class †Cephalaspidomorphi Kiaer & Stensiö, 1920 see Class Osteostraci Lankester, 1868
     Subclass †Osteostraci Lankester, 1868 see Class Osteostraci Lankester, 1868
       Order †Cephalaspidiformes Halstead Tarlo, 1967
         1 Suborder †Cephalaspidoidei Halstead Tarlo, 1967