Class Mammalia Linnaeus, 1758 - mammals
   Subclass Theria Parker & Haswell, 1897
     Order Carnivora Bowdich, 1821 - carnivores
       Suborder Caniformia Kretzoi, 1943
         Family Mustelidae Batsch, 1788 - weasels, badgers, skunks, and otters
           Subfamily Lutrinae Bonaparte, 1838 - otters
             Genus Aonyx Lesson, 1827 - clawless otters
               Aonyx cinerea (Illiger, 1815) - Oriental small-clawed otter
                 1 [Aonyx cinerea cinerea] (Illiger, 1815)
                 2 Aonyx cinerea concolor Rafinesque, 1832
                 3 Aonyx cinerea nirnai Pocock, 1940