Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Craniata Linnaeus, 1758 see Subphylum Vertebrata Cuvier, 1812
     Pisces
       Class Elasmobranchii Bonaparte, 1838 see Subclass Elasmobranchii Bonaparte, 1838
         Order Torpediniformes - electric rays
           1 Family Narkidae Fowler, 1934 see Subfamily Narkinae
           2 Family Narcinidae Gill, 1862
           3 Family Hypnidae Gill, 1862 see Subfamily Hypninae
           4 Family Torpedinidae Henle, 1834 - electric rays