Great Diving Beetle

aquatic insects · pond predators · Europe and Asia

Expert underwater swimmer. The great diving beetle has flat, paddle-like hind legs that work like oars to propel it through ponds and streams. It can dive deep and maneuver with amazing speed to catch prey.

Scary larva form. Young great diving beetles, called larvae, grow much bigger than the adults, reaching up to 60 millimeters long. These larvae are fierce hunters with powerful jaws that snap shut on fish, tadpoles, and other insects.

Size difference mystery. Adult great diving beetles are smaller than you might expect, measuring only 27 to 35 millimeters long, which is about the size of your pinky fingernail. Yet they are still considered large for beetles.

Found across the north. This beetle lives in Europe and northern Asia, and is especially common in Wales and much of England and Scotland. It thrives in cool ponds, lakes, and slow-moving streams.