From Ohio History Central
Adult Diving Beetle
There are over 300 species of diving beetles (Dytiscus sp.) in North America, making it the largest American family of water bugs. They are found in habitats of standing water of ponds and streams, especially with a muddy bottom.
Diving beetles are usually black or brown and oval-shaped. Adults average one-sixteenth to two-inches long, with a piercing-sucking mouth type. Their hind legs are made for swimming. Diving beetles get their name from their ability to grab and carry air bubbles at the end of their abdomen, enabling them to breath from the bubbles while swimming under water.
In some American Indian cultures, there are stories that credit the diving beetle in bringing up the first earth (soil) when the world was covered with water.
The diving beetle is also known as the predacious diving beetle. This name reveals this insect