vertebrates Lamarck, 1801 - vertebrates see Infraphylum Vertebrata Lamarck, 1801
Count: [†*] †2o;3f;119g;16s
   †Pteraspidimorphi [paraphyletic]
  Count: [†*] †2o;3f;119g;16s
     †Heterostraci Lankester, 1868, sedis mutabilis - heterostracans
    Count: [†*] †2o;3f;106g;16s
       Family †Cyathaspididae Kiaer, 1932, nom. praeval. [paraphyletic]
      Count: [†*] †2o;1f;102g;13s
         †Problematic Heterostraci [paraphyletic]
        Count: [†*] †1f;28g;3s
           Family †Amphiaspididae Obruchev, 1939
          Count: [†*] †21g
             Genus †Gerronaspis Novitskaya, 1971, sedis mutabilis
            Count: -