Superphylum Deuterostomia Grobben, 1908 - deuterostomes see Infrakingdom Deuterostomia Grobben, 1908
   Phylum Chordata Bateson, 1885 - chordates
     Subphylum Craniata auct. see Subphylum Vertebrata Cuvier, 1812
       Vertebrata (Lamarck, 1801) - vertebrates see Subphylum Vertebrata Cuvier, 1812
         Superclass Petromyzontomorphi [monotypic]
           Class Petromyzontida [monotypic] - lampreys
             Order Petromyzontiformes Berg, 1940 - lampreys
               Family Petromyzontidae Bonaparte, 1832, sedis mutabilis - lampreys
                 Subfamily Lampetrinae
                   Genus Caspiomyzon Berg, 1906 [monotypic]
                     1 Caspiomyzon wagneri (Kessler, 1870) - Caspian lamprey