Sea Squirts: Ascidiacea

Physical characteristics: Distaplia cylindrica sea squirts form sausage-shaped colonies that reach a length of 23 feet (7 meters) and a width of 3 inches (8 centimeters). The colony is white or yellowish and has a soft texture. It is attached at one end to rocks and grows upward. The individual sea squirts in the colony are small and are located only in the surface layer of the colony, where they form many small, oval systems.

Geographic range: Distaplia cylindrica (abbreviated to D. cylindrica) sea squirts live in the Antarctic regions.

Habitat: D. cylindrica sea squirts live on rocky bottoms.

Distaplia cylindrica sea squirts live in the Antarctic regions. (Illustration by Emily Damstra. Reproduced by permission.)

Diet: D. cylindrica sea squirts eat nutrient particles they strain from the water flowing through them.

Behavior and reproduction: D. cylindrica sea squirts attach themselves to rocks. They make both eggs and sperm, but individual sea squirts in different parts of a colony may have better developed male organs and those in another part of the colony may have better developed female organs. Larvae develop in pouches in the parent colony.

Distaplia cylindrica and people: D. cylindrica sea squirts have no known importance to people.

Conservation status: D. cylindrica sea squirts are not considered threatened or endangered. ∎