Nepidae, commonly known as water scorpions, are a family of aquatic insects found in freshwater habitats worldwide. They have long, slender bodies with powerful forelegs adapted for grasping prey. Water scorpions possess a long, tubular breathing tube called a siphon, which they use to access air while submerged. They are predators, feeding on small aquatic organisms such as insects, crustaceans, and even small fish.