Pontastacus leptodactylus

Pontastacus leptodactylus, the Danube crayfish, Galician crayfish, Turkish crayfish or narrow-clawed crayfish, is a relatively large and economically important species of crayfish native to fresh and brackish waters in eastern Europe and western Asia, mainly in the Pontic–Caspian region, among others including the basins of the Black Sea, and the Danube, Dnieper, Don and Volga rivers, as well as aquatic systems in Turkey. It has spread widely beyond its native range, beginning in the 1700s when it spread via canals constructed in western Russia and since the 1900s through introducions to many regions for human consumption. Today it is widespread throughout much of Europe.