Believe it or not, these strange animals belong to the same phylum as you and me. We share one common feature with these animals - a neural chord string. The similarities stops there. Many species are filter eaters and have two openings or siphons. Water is sucked into one and expelled out through the other. They get nutrition from plankton, extracted from the water. Some species are sessile, others free-swimming, some are colonial others solitary. Most tunicates are hermaphrodites.
The tunicates are all marine species and include four classes:
- The sea squirts (Ascidiacea) are sessile filter feeders. There are both colonial and solitary sea squirts.
- The salps (Thaliacea) include both solitary and colonial, free-swimming tunicates.
- The Larvaceans (Larvacea) are solitary, free-swimming species.
- Sorberacea is a class of benthic animals that have a dorsal nerve cord in the adult life stage, in contrast to the sea squirts.