Creeping Water Bugs (Family Naucoridae), are aquatic bugs usually seen creeping along the bottom of gravel streams. They are small bugs, but broad and flattened, with forelegs modified into what look like huge "pinchers" in the front. They apparently use these legs to grasp the substrate in their riffles, evidenced by the way this little bug gripped the palm of my hand.

It seems that every stream in the desert with a Naucorid bug has a different species, and that each is endangered.

This creeping water bug, Ambrysus mormon, was found crawling on a rock wall in Zion National Park where a spring higher on the wall produced a small flow of water.