Deep-sea crustaceans are marine animals that belong to the class Malacostraca, which includes species like shrimp, crabs, and lobsters. They inhabit the ocean's depths, often living at depths greater than 200 meters. These creatures have adapted to extreme conditions, such as high pressure and low temperatures, and they play a crucial role in the ocean's ecosystem by serving as both predators and prey. Many deep-sea crustaceans possess unique features, such as bioluminescence, which helps them attract mates or evade predators. Some well-known examples include the Giant Isopod and the Amphipod. These organisms contribute to nutrient cycling in the deep sea, making them essential for maintaining the health of marine environments.