Sprat

sprat Sprattus sprattus sprattus, a small fish (maximum length 14 cm/5.5") of the herring family which abounds in coastal waters of the Mediterranean and NE Atlantic. It can survive in waters of low salinity, such as those of the Baltic, where it exists in the form of a subspecies S. s. balticus.

The Caspian sprat, Clupeonella cultiventis, belongs to the Caspian and Black seas, where it evolved at a time when the Black Sea was not connected to the Mediterranean. It is slightly larger (to 17 cm/6").