Geographical patterns in range extension of Ponto-Caspian macroinvertebrate species in Europe

Range extensions of aquatic Ponto-Caspian macroinvertebrate species in Europe have mainly been facilitated by the interconnection of river basins through man-made canals and intentional introductions. Three inland migration corridors can be distinguished: (i) a northern corridor: Volga [Formula: see text] Lake Beloye [Formula: see text] Lake Onega [Formula: see text] Lake Ladoga [Formula: see text] Neva [Formula: see text] Baltic Sea, (ii) a central corridor connecting the rivers Dnieper [Formula: see text] Vistula [Formula: see text] Oder [Formula: see text] Elbe [Formula: see text] Rhine, and (iii) a southern corridor connecting the Danube and Rhine rivers. Important trade harbours in Europe were connected…