vertebrates Lamarck, 1801 - vertebrates see Infraphylum Vertebrata Lamarck, 1801
   †Pteraspidimorphi [paraphyletic]
     †Heterostraci Lankester, 1868, sedis mutabilis - heterostracans
       Family †Cyathaspididae Kiaer, 1932, nom. praeval. [paraphyletic]
         †Problematic Heterostraci [paraphyletic]
           1 †Corveolepis arctica
           2.1.1 †Corveolepis elgae
           2.1.2.1 †Traquairaspis mackenziensis sedis mutabilis
           2.1.2.2 Genus †Natlaspis Dineley & Loeffler, 1976, sedis mutabilis
           2.1.2.3 †Tesselate Heterostraci sedis mutabilis
           2.2 Family †Amphiaspididae Obruchev, 1939