Amphipoda is a class of small, shrimp-like crustaceans found in various aquatic environments, including oceans, freshwater, and even moist terrestrial habitats. They typically have a laterally compressed body and can range in size from a few millimeters to several centimeters. Amphipods play a crucial role in the ecosystem as scavengers and prey for larger animals. These creatures are characterized by their segmented bodies and jointed limbs, which allow for agile movement. Some well-known examples of amphipods include sand fleas and scuds. They are important indicators of environmental health and contribute to the food web in their respective habitats.