Ascidia

What Is Phylum Urochordata (Tunicata)? Phylum Urochordata, commonly called Tunicata, is a group of exclusively marine chordates found in oceans around the world. They are commonly known as tunicates because their body is covered by a protective outer covering called the tunic. Urochordates have a sac-like or barrel-shaped body with two openings called incurrent and