Epioblasma obliquata (Purple Cat's Paw (=Purple Cat's Paw Pearlymussel)) is a species of mussels in the family unionid freshwater mussels. They are associated with freshwater habitat.
Comment: "Small" is ambiguous. For details on "Small rivers" (e.g. the Salween river) see http://worldwildlife.org/biomes/small-river-ecosystems. This class will be replaced with a less ambiguous class.