Class Mammalia Linnaeus, 1758 - mammals
   Order Carnivora Bowdich, 1821 - carnivores
     Family Mustelidae Batsch, 1788 - weasels, badgers, skunks, and otters
       Subfamily Lutrinae Bonaparte, 1838 - otters
         Genus Lutra Brisson, 1762 - river otters
           1 Lutra lutra (Linnaeus, 1758) - European otter
           2 Lutra maculicollis Lichtenstein, 1835 - spotted-necked otter see Hydrictis maculicollis (Lichtenstein, 1835)
           3 Lutra sumatrana (Gray, 1865) - hairy-nosed otter