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Mysis sp.
Mysids, opossum shrimps
Misidaceos, camaroncitos

Phylum Arthropoda
Class Crustacea
Subclass Malacostraca
Order Mysidacea


Mysids look very much like little shrimps. Females possess a marsupium, or brood pouch, hence the common name of opossum shrimps. Their elongated body is usually transparent, with a thin carapace, and stalked compound eyes. They have several sensory organs used for balance and orientation called statocysts. About 780 mysidaceans have been described.

Size: The majority of mysids measure 1.5 to 3 cm. in length.

Range and Habitat

Most species are marine and are found at all depths.

Natural History

Mysids move their appendages very fast and are rapid swimmers. They swim close to the bottom. Marine species often live in large swarms and form an important part of the diet of many fish and invertebrates. Sometimes, in conditions of upwelling, one can find clouds of mysids so dense that they can obscure one's vision, and at times, only their shadows reveal their presence.

Mysids are a very important part of the ocean richness that provides nourishment for all life.

cloud of mysids, from Ocean Oasis © 2000 CinemaCorp of the Californias

Cloud of mysids — from Ocean Oasis

Text by Patricia Beller
Photograph from Ocean Oasis © 2000 CinemaCorp of the Californias

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