Pomatoschistus marmoratus, 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 at depths of from 20 to 70 metres (66 to 230 ft). It can reach a length of 8 centimetres (3.1 in) TL though most do not exceed 5 centimetres (2.0 in) TL.