Soestia zonaria

Taxon-Order: 

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Distribution: 
Cosmopolitan.
Size: 
Aggregate generation: to 60 mm; solitary generation: to 50 mm
Diet: 
Filter feeders; phytoplankton and other small particles.
Predators: 
Medusae, siphonophores, ctenophores, heteropods, sea turtles, marine birds and many fish.
Useful Facts or Characters: 

The aggregate generation zooid possesses a thick, rigid tunic.  All body muscle bands are very clear and wide with body muscle band 1 dorsally interrupted and body muscle band 5 split on the left side when in dorsal view.   The solitary generation zooid is prismatic in shape with pointed posterior projections and possesses a thick test with even thicker clearly visible body muscle bands compared to the aggregate generation. 

References: 

Bone, Q. (1998) The biology of pelagic tunicates. Oxford University Press, Oxford.

Wrobel, D. and Mills, C. (1998) Pacific Coast pelagic invertebrates:  a guide to the common gelatinous animals. Sea Challengers, Monterey Bay Aquarium, Monterey, CA.

Yount, J.L. (1954) The taxonomy of the Salpidae (Tunicata) of the central Pacific Ocean. Pacific Science 8: 276-330.