- Kingdom: Animalia
- Phylum: Chordata
- Subphylum: Tunicata
- Class: Ascidiacea
- Order: Phlebobranchia
- Family: Cionidae
- Scientific name: Ciona intestinalis
- Norwegian: tarmsjøpung
The sea vase comes in shades of green or blue, but the light yellow coloration is more frequent. The body length may reach 25 cm, but 15 cm is normal. The inlet siphon is on the top of the body, while the outlet is found on the side, not far from the top. The siphon margins are often white or pale yellow, sometimes with yellow spots.
This species is very popular among scientists doing research on chordate genetics, due to its very simple genetic structure. This is the banana fly of the chordates.
You may find it on hard substrate on all depths down towards 1000 meters.
This species has a worldwide distribution.