Pseudocumatidae are a family of crustacean

Crustacean

Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...

s of the order Cumacea

Cumacea

Cumacea is an order of small marine crustaceans, occasionally called hooded shrimp. Their unique appearance and uniform body plan makes them easy to distinguish from other crustaceans.-Anatomy:...

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Anatomy

Pseudocumatidae have a small, free telson

Telson

The telson is the last division of the body of a crustacean. It is not considered a true segment because it does not arise in the embryo from teloblast areas as do real segments. It never carries any appendages, but a forked "tail" called the caudal furca is often present. Together with the...

. The uropods bear endopods (interior branch) on one segment. The males have two pairs of rather rudimentary pleopods and the flagella of the second antenna reach far beyond the pereon. In females the second antenna much is smaller than the first antenna.