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Marine Animal Encyclopedia

Star Sea Squirt Botryllus schlosseri

Individual star sea squirts are only about in (2 mm) long and cannot live on their own. Instead, they arrange themselves in star-shaped clusters, or colonies, embedded in a shared gelatinous casing, called a tunic or test. At the center of each star is a shared outgoing (exhalent) opening through which used water is voided. The colonies vary greatly in color and may be green, violet, brown, or yellow, with the individuals having a contrasting color to the test.

Star Sea Squirtzoom image
  • Subphylum Urochordata
  • Width_cluster Up to 6 in (15 cm)
  • Depth Shore and shallows
  • Habitat Rock, stones, seaweeds
  • Distribution Coastal Arctic and temperate waters of north Atlantic
Star Sea Squirt habitat mapzoom image