Class Mammalia Linnaeus, 1758 - mammals
   Order Carnivora Bowdich, 1821 - carnivores
     Family Mustelidae Batsch, 1788 - weasels, badgers, skunks, and otters
       Subfamily Lutrinae Bonaparte, 1838 - otters
         1 Genus Amblonyx Rafinesque, 1832 see Genus Aonyx Lesson, 1827
         2 Genus Aonyx Lesson, 1827 - clawless otters
         3 Genus Enhydra Fleming, 1822 - sea otter
         4 Genus Lontra Gray, 1843
         5 Genus Lutra Brisson, 1762 - river otters
         6 Genus Lutrogale Gray, 1865
         7 Genus Pteronura Gray, 1837 - giant otter