Vertical Diving Beetle

taken from bugguide.net

Larvae of predatory diving beetles are also known as water tigers. They are predatory and their mandibles have grooves on their inner edge through which they are able to suck the body fluids of their prey. Some of them can kill small vertebrates such as tadpoles.

The beetle swims by moving its hindlegs in unison, like oars. Diving beetles collect air at the surface in a “bottoms-up pose, trapping a bubble beneath their wing covers. This allows them to breath under water similar to a scuba diver.

Members of this species are pretty big, ranging up to 4 cm long. The larva can even get as long as 5 cm. Nevertheless, they fly well and are often attracted to lights at night.

To us humans these beetles do a great service as they are predators that can reduce the number of mosquito larvae.