Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Craniata Linnaeus, 1758 see Subphylum Craniata auct.
     Pisces
       Class Elasmobranchii Bonaparte, 1838 see Infraclass Elasmobranchii Bonaparte, 1838
         Order Rajiformes Berg, 1940 - skates
           01 Family Rhinobatidae Bonaparte, 1835 - guitarfishes
           02 Family Arhynchobatidae Fowler, 1934 - softnose skates
           03 Family Rajidae Blainville, 1816 - hardnose skates
           04 Family Anacanthobatidae von Bonde & Swart, 1923 - legskates
           05 Family Plesiobatidae Nishida, 1990 - deepwater stingrays
           06 Family Hexatrygonidae Heemstra & Smith, 1980 - sixgill stingrays
           07 Family Dasyatidae Jordan & Gilbert, 1879 - whiptail stingrays
           08 Family Gymnuridae Fowler, 1934 - butterfly rays
           09 Family Myliobatidae Bonaparte, 1835 - eagle rays
           10 Family Urolophidae Müller & Henle, 1841 - round stingrays
           11 Family Potamotrygonidae Garman, 1877 - neotropical stingrays
           12 Family Urotrygonidae McEachran, Dunn & Miyake, 1996 - American round stingrays