• Mysis is genus of mysid crustaceans in the family of mysidae, distributed mainly in the coastal zone of Artic and high boreal seas.

• Several species also inhibit northern fresh water lakes and the brackish Caspian Sea.

• Body length range from1 to 3 centimeters (0.4 to 1.2 inches).

• All the thoracic appendages are biramous.

• Even the 5 pairs of posterior thoracic legs are biramous with flagellar exopodite which take up the locomotorey function.

• The abdomen develops similar to that of the adult form with 5 pairs of biramous Pleopods and a pair of uropods and a telson.