There are 19 species of Giant Water Bugs in the US. This family is the largest in size in the order Hemiptera with US species ranging around 2 ½” long. These bugs are fierce predators and will prey on a variety of aquatic insects including snails, small fish, and baby turtles. They are known to play dead when approached by humans, but beware, they will give a painful bite! Here’s an article that talks about their bites: Bites Caused by Giant Water Bugs Belonging to Belostomatidae
It is the males of this family that care for the eggs; the female role is to find the male to fertilize her. She then lays the eggs on the back of the male who will protect them until they hatch.