Great diving beetle male by Nick Goodrum 1/2
Great diving beetle by Chris Durdin 2/2

Great Diving Beetle Dytiscus marginalis

The great diving beetle can be found in garden pools, and may grow up to 30mm. These attractive insects look black, but their backs are actually green.

Conservation status

Widespread and common. Not threatened.

Related questions & advice

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Did you know?

The adult great diving beetle stores air beneath its wing cases to allow it to stay underwater for longer to hunt.

The larvae and adult great diving beetle are carnivorous. The larvae feed on other insects, tadpoles and even small fish catching prey in their large jaws then injecting enzymes into the body. These enzymes dissolve the victim’s internal organs which are then sucked into the diving beetle’s mouth.

During the evening and night adult diving beetles sometimes leave the water and can fly long distances colonising new ponds.

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