Amphipoda

Amphipoda () is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods () range in size from 1 to 340 millimetres (0.039 to 13 in) and are mostly detritivores or scavengers. More than 10,700 amphipod species are currently recognized. They are mostly marine animals but are found in almost all aquatic environments. Some 2,250 species live in fresh water, and the order also includes the terrestrial sandhoppers, such as Talitrus saltator and Arcitalitrus sylvaticus.

Gammaridea was one of the suborders of the order Amphipoda, comprising small, shrimp-like crustaceans. In a traditional classification, it encompassed about 7,275 (92%) of the 7,900 species of amphipods described by then, in approximately 1,000 genera, divided among around 125 families. That concept of Gammaridea included almost all freshwater amphipods, while most of the members still were marine.

Hyperiopsidae is a family of amphipods, comprising the genera Hyperiopsis and Parargissa.