Pomatoschistus marmoratus, the marbled goby, is a species of goby native to the eastern Atlantic from the Bay of Biscay down around the Iberian Peninsula through the Mediterranean Sea, the Black Sea and the Sea of Azov. It is also found in the Suez Canal in Egypt. It occurs in marine and brackish waters on sandy substrates in shallow waters, typically down to 20m (70feet), but occasionally to 70m (230feet) in the winter. It can reach a length of 8cm (03inches) TL though most do not exceed 5cm (02inches) TL.