Description
This sea-squirt is named due to its rough cartilaginous shell that stays dirty. It is a common sea squirt with an egg-shaped body. At the top it is slightly narrower than at the bottom. It can be confused with the Ascidiella scabra, which has a smooth mantle with only around the inflow and outflow openings small warts. Tunicates are both male and female (hermaphrodites). Reproduction takes place by separation of sperm into the water. The sperm enters through the oral sifon and is than fertilized inside the body. Fertilization also can takes place outside the body.

Size
The maximum size is 10 cm.

Colour
The sea squirt is usually translucent gray to gray-brown.

Habitat
From shallows to about 90 meters depth.

Distribution
North Eastern Atlantic, from Norway to the Mediterranean.