The wheel bug (Arilus cristatus), in the family Reduviidae, is one of the largest terrestrial true bugs in North America, reaching up to 1.5 inches (38 mm) in length in their adult stage. A characteristic structure is the wheel-shaped pronotal armor. They are predators upon soft-bodied insects such as caterpillars, Japanese beetles, etc., which they pierce with their beak to inject salivary fluids that dissolve soft tissue. Because most of their prey are pests, wheel bugs are considered as beneficial to the garden as ladybugs. They are also known for eating stinkbugs.