Tunicata

Tunicata (also known as Urochordata) is a subphylum of aquatic invertebrates, comprising some 3,000 species of tunicates. They are characterised by their ability to form tough, leathery, protective outer coats or tunics which protect them from predators and environmental changes. These animals play an important role in marine and freshwater ecosystems, being able to filter water and reduce the amount of organic particles and nitrogen compounds. They are also a food source for many larger animals such as fish, crustaceans and molluscs. Tunicates are also used in a variety of medical applications, such as the production of anti-cancer drugs, and have been studied for their potential ability to produce energy.