| Category | Classification |
| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Mammalia |
| Order | Carnivora |
| Family | Mustelidae (Otters) |
| Genus species | Aonyx capensis (Cape Clawless Otter) Enhydra lutris (Sea Otter) Aonyx cinerea (Oriental Small-Clawed Otter) Aonyx congica (Congo Clawless Otter) Lutra canadensis (North American River Otter) Lutra felina (Marine Otter) Lutra longicaudis (Neotropical Otter) Lutra lutra (Eurasian Otter) Lutra maculicicolis (Spotted-necked Otter) Lutra perspicillata (India Smooth-coated Otter) Lutra provacoax (Southern River Otter) Lutra sumatrana (Hairy-nosed Otter) Pteronura brasiliensis (Giant Otter) |