Kingdom Animalia Linnaeus, 1758 - animals
   Phylum Craniata Linnaeus, 1758 see Subphylum Vertebrata Cuvier, 1812
     Pisces
       Class Actinopterygii Woodward, 1891 - ray-finned fishes
         Order Osteoglossiformes Berg, 1940 - bonytongues
           1 Family Osteoglossidae Bonaparte, 1845 - bonytongues and arapaimas
           2 Family Arapaimidae Bonaparte, 1846
           3 Family Pantodontidae Peters, 1876
           4 Family Hiodontidae Cuvier & Valenciennes, 1846 - mooneyes
           5 Family Notopteridae Bleeker, 1851 - knifefishes
           6 Family Mormyridae Bonaparte, 1831 - elephantfishes
           7 Family Gymnarchidae Bleeker, 1859