[Phylum] Chordata Bateson, 1885 - chordates
   Subphylum Craniata auct.
     Infraphylum Vertebrata Lamarck, 1801 - vertebrates
       Superclass †Pteraspidomorphi Goodrich, 1909 [monotypic]
         Class †Pteraspidomorpha
           Subclass †Heterostraci Lankester, 1868
             Order †Tesseraspidiformes Halstead, 1962 [monotypic]
               Family †Tesseraspididae Berg, 1955, nom. praeval.
                 1 Genus †Tesseraspis Wills, 1935
                 2 Genus †Natlaspis Dineley & Loeffler, 1976