The red-mouthed goby (Gobius cruentatus) is a species of goby native to the Eastern Atlantic Ocean from southwestern Ireland to the coasts of Morocco and Senegal, and also in the Mediterranean Sea where it occurs in inshore waters at depths of from 15mto40mm (49feetto130feetm) in areas with rocky or sandy substrates or in meadows of sea-grass. This species can reach a length of 18cm (07inches) TL. It may also be found in the aquarium trade.