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Where are free-swimming tunicates found in the ocean?
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tunicate
Blue spot sea squirt (Clavelina moluccensis), a colonial tunicate.
Free-swimming tunicates are found throughout the world's oceans, ranging from polar regions to the tropics. These organisms exist as plankton in open water, where they are classified as pelagic.12
Specific groups of free-swimming tunicates occupy different marine environments:
- Appendicularians: These small, simple organisms spend their entire lives in the open sea.3
- Thaliaceans: This group, which includes salps, dolioloids, and pyrosomes, is also pelagic, adapted specifically for life in open water. Salps, in particular, are frequently found in warm seas and are especially common in the Southern Hemisphere.34
Unlike sessile forms that attach to solid surfaces like rocks or ship hulls, free-swimming tunicates remain mobile throughout their lives, often using jet propulsion or tail undulation to navigate the water column.135