Description
Great Diving Beetles (Dytiscus marginalis) are one of the largest aquatic beetles in the world and can grow up to about 2 inches, or roughly 5.8cm. Apart from this they have the same diving beetle features. They live worldwide, and are the largest of the diving beetle family, and the most known type too.
Larvae
The larvae of a Great diving beetle are very fierce, eating everything they can reach, tadpoles, fish, sometimes even other larvae. They swim with their tails extended upwards, taking the appearance of a scorpion. To receive oxygen, they stick their tails out of the water to take in air through the terminal spiracle, or air hole. They are lighter than the water and to stay under water they have to cling on to weeds.