World Amphipoda Database

The amphipods belong to the very diverse crustacean class Malacostraca, which includes other common groups such as crabs, lobsters and shrimp. The order Amphipoda is part of the superorder Peracarida, uniting a diverse group of small shrimp-like taxa that brood their young in a pouch, with no independent larval dispersal stage. Amphipods are unique in the possession of three pairs of pleopods and three pairs of uropods. In a small minority of cases secondary reduction of the abdomen may result in a loss of one or more pairs (e.g. the Caprellidae). No other malacostracan group possesses more than one pair of uropods. The name Amphipoda means ‘different feet’ and refers to the different forms of the pereopods (legs) which contrasts with the related Isopoda meaning ‘same feet’. Amphipods are variously known as, scuds, shrimp or sideswimmers. Those amphipods that have colonised the land are often referred to as landhoppers and beach dwellers are called sandhoppers or beach/sand fleas.