#structural appendages

• Amphipod — A small malacostracan crustacean belonging to the order Amphipoda, characterized by the absence of a carapace, a laterally compressed body, and legs structurally adapted for different functions (some for walking, others for swimming or jumping). Most species live in marine or freshwater environments (such as the beach flea or the genus Gammarus), playing an essential ecological role in aquatic food webs.