The term
shrimp is a generic term for some
decapod crustaceans, although the exact animals covered can vary. Used broadly, it may cover any of the groups with elongated bodies and a primarily swimming mode of locomotion – chiefly
Caridea and
Dendrobranchiata. In some fields, however, the term is used more narrowly, and may be restricted to Caridea, to smaller species of either group, or to only the marine species. Under the broader definition,
shrimp may be synonymous with
prawn, covering stalk-eyed swimming
crustaceans with long narrow muscular tails (abdomens), long whiskers (
antennae), and slender legs. They swim forward by paddling with
swimmerets on the underside of their abdomens.
Crabs and
lobsters have strong walking legs, whereas shrimp have thin fragile legs which they use primarily for perching.