Pleurobrachia bachei

Taxon-Order: 

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Distribution: 
Alaska to Mexico.
Habitat: 
Pelagic, near shore; common in aggregations.
Size: 
Up to 15 mm.
Diet: 
Copepods, larval fish, and other small plankton.
Useful Facts or Characters: 

It is not a jellyfish.  Commonly called the sea gooseberry for its shape; has eight equally-spaced ctene rows that extend the full length of the body.

Natural History: 

Lacks bioluminesence and can be very common in the San Diego area.