Description
The most characteristic feature of this sea cucumber is the Cuvierian organ. This organ is ejected as a sticky mass of threads, when the animal is threatened or disturbed. Also the intestines can be ejected and will regenerate after some time.

Size
The average size is between 20 and 40 cm.

Colour
Usualy black but also mottled brown, yellow or reddish brown. The dorsal papillae have a white tip, but can be completely white with a white disc. The terminal disc of the tube feet is white.

Habitat
Prefer rocky sea floors.

Distribution
North Atlantic ocean, Mediterranean sea and Black sea.