Tunicata
Sea tulips, Pyura spinifera. A symbiotic sponge covers its surface.
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Subphylum:	Tunicata Giribet et al 2000

Bluebell tunicates

Colonies of tunicate Botrylloides violaceus. Note new zooid buds within colonies and along margins of colonies.

Colony of Botryllus.

Tunicates (sea squirts or Urochordata) are a subphylum of the Chordates.

They are sea filter-feeders: they live mainly on plankton. They are called tunicates because the adult form is covered by a leathery tunic. This tunic supports and protects the animal. The adults are sessile, stuck to rocks.

Many tunicates are colonial or semi-colonial in their adult stage. They are quite a large group, containing about 3,000 species. The adults live mostly on the sea floor, in the littoral zone.