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
         Myopterygii - myopterygians
           Superclass Gnathostomata Gegenbaur, 1874 - jawed vertebrates
             Grade Chondrichthiomorphi
               Class Chondrichthyes Huxley, 1880 - cartilaginous fishes
                 Subclass Elasmobranchii Bonaparte, 1838 - shark-like fishes
                   Infraclass Euselachii Hay, 1902 - sharks and rays, and related fossils
                     Division Neoselachii Compagno, 1977
                       Subdivision Batoidea - rays
                         Order Rajiformes Berg, 1940 - skates
                           Family Rajidae Blainville, 1816 - skates
                             Subfamily Arhynchobatinae see Family Arhynchobatidae Fowler, 1934
                               Genus Rioraja Whitley, 1939 [monotypic]