Subphylum [Vertebrata] Cuvier, 1812 - vertebrates
   Class Agnatha Cope, 1889
     Subclass †Thelodonti Kiaer, 1932
       Order †Furcacaudiformes Wilson & Caldwell, 1998 - forktail thelodonts
         ?Family †Barlowodidae Märss, Wilson & Thorsteinsson, 2002
           1 Genus †Barlowodusᵀ Märss, Wilson & Thorsteinsson, 2002
           2 Genus †Sophialepis Märss, Wilson & Thorsteinsson, 2002 [monotypic]