Pyrosome

Genus of marine filter-feeders

Pyrosomes, genus Pyrosoma, are free-floating colonial tunicates that usually live in the upper layers of the open ocean in warm seas, although some may be found at greater depths. Pyrosomes are cylindrical or cone-shaped colonies up to 18 m (60 ft) long, made up of hundreds to thousands of individuals, known as zooids. Colonies range in size from less than one centimeter to several metres in length. They are commonly called "sea pickles". Other nicknames include "sea worms", "sea squirts", "fire bodies", and "cockroaches of the sea".

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