The common smooth-hound (Mustelus mustelus) is a houndshark of the family Triakidae. It is found in the eastern Atlantic Ocean from the British Isles to South Africa, and in the Mediterranean Sea, Madeira, and the Canary Islands at depths ranging from 5 m to 625 m (although they usually stay at depths between 5-50m). While they can grow to 200 cm, their usual maximum size is 150 cm. They commonly grow to 100–120 cm with a birth length around 35 cm.The reproduction of commons smooth-hounds is viviparous.