The Great Diving Beetle is a large aquatic insect that can be found in weedy ponds, lakes and garden ponds.  It has the name ‘Great Diving Beetle’ because it sometimes dives in water when it sees prey and dives into mud when it is disturbed. 

The Great Diving Beetle is about three centimetres long and has a long slender-looking body that is dark brown or black.  It also has a yellow border around its black head and a yellow border around its thorax which is the middle part of its body.  The thorax also holds three pairs of yellow legs and two sets of wings.  The hind wings are soft and are used for flying and the front wings are quite hard.  The front wings are called 'elytra' and they cover and protect the soft hind wings when the beetle is not in flight. The female Great Diving Beetle has ridges running down the length of her elytra and the male has a smooth elytra.

Great Diving Beetles often fly at night, especially to other ponds if food is scarce.  They are strong beetles and will attack and kill tadpoles, young fish and minnows.  They also eat insects.  The larvae of these beetles eat tadpoles, insects and even other Great Diving Beetle larvae. Great Diving Beetles can also release a foul-smelling fluid when they feel threatened which stops some predators from attacking them.