Distribution
Europe and Asia: Loire drainage in France eastward, in nearly all rivers draining to southern Baltic, North, Black and Azov Seas; Caspian basin, in upper Volga and from Kura drainage southward to Iranian tributaries of Caspian; widespread in Iran. In Mediterannean basin, only in Rh?ne and some small coastal drainages from Provence (France) eastward to Genova (Italy), Aoos (Greece, Albania) and western Greece as far south as Sperchios drainage. In Marmara basin, western Anatolia south to Great Menderes drainage and in upper Euphrate and Tigris drainages. Aral basin, upper Amu Darja and Karakumskij drainages (Tukmenistan, Afghanistan). Appendix III of the Bern Convention (protected fauna).