Caprillies, also known as caprellids, are small marine crustaceans that belong to the order Amphipoda. They are often found in coastal waters, where they inhabit algae, seagrasses, and other substrates. Caprillies play a role in the marine ecosystem as both grazers and prey, contributing to nutrient cycling and serving as food for various fish and invertebrates. Their distinct elongated bodies and unique locomotion set them apart from other amphipods.