Fishes
   Class Actinopterygii Woodward, 1891 - ray-finned fishes
     Order Anguilliformes Rafinesque, 1810 - eels
       Family Synaphobranchidae Johnson, 1862 - cutthroat eels
         1 Subfamily Ilyophinae - arrowtooth eels
         2 Subfamily Synaphobranchinae - cutthroat eels
         3 Subfamily Simenchelyinae - pugnose eels