: the species is currently present in 13 of them (endemic, native, introduced);
: possible in 0 of them (stray, questionable);
: absent from 0 of them (extirpated, not established, misidentification, error).
: all reports listed together.
Distribution: Euorpe: Black Sea basin; Maritza and Struma drainages in eastern Aegean basin. In Danube, present up to about Vienna, invasive since 1970s, now reaching upstream to southern Germany. In South Bug and Dniepr native far upriver. Introduced to North America in 1991 through ballast of ships.
The map in this page was supported by BioFresh that has received funding from the
European Union's Seventh Programme for research, technological development and demonstration under grant agreement No 226874