Pistol or snapping shrimps are a diverse group of crustaceans comprising around 600 species, mostly in the genera Alpheus and Synalpheus.
They all have asymmetrical claws, and the larger one can produce a supersonic snapping sound. Instead of pincers, it has a pistol-like appendage made of two parts.
A special joint enables the “hammer” to click backward into a perpendicular position. Upon release, it snaps into the other part of the claw, generating a powerful wave of bubbles that can even stun larger fish and break small glass jars.
Pistol shrimp can interfere with sonar communication when living in colonies, and are believed to be the main source of natural noise in the world’s oceans.
You can watch a hunting pistol shrimp in action in this video.
Matthew Oldfield is a freelance photographer based in Bali, Indonesia, specializing in editorial and documentary images from both above and below the waves. He works primarily with charities, NGO’s, and other organizations working to conserve the environment, endangered species, and disappearing cultures.