The Wheel Bug (Arilus cristatus) is an assassin bug species and one of the largest terrestrial true bugs in North America. They are most common in eastern Canada and the United States. They are known for their wheel-shaped pronotal armor. As Wheel Bugs mostly prey on pests like Japanese beetles, cabbage worms, and tent caterpillars, they are considered beneficial. The species is known to be very shy; they reside in leafy areas and hide whenever it is possible. Physically Wheel Bugs have membranous wings; they are gray or black with bright red or orange abdomens.