Wheel Bug (Arilus cristatus)

Wheel bugs are one of the most distinctive insects in North Carolina; they are easily identifiable by a pronounced (and very odd) projection that arcs up from their backs. Once you see one wheel bug up close, other individuals are easy to identify at a glance.

Close up of an assassin bug called a wheel bug (Arilus cristatus). This insect has a light gray body with black-tipped wings, six spindly legs, red antennae and a red three-segmented beak which is held underneath its long, skinny head. Its thorax has a sharply raised protuberance edged in jagged spikes that make the insect's back resemble half a cogwheel.
Close up of an assassin bug species called a wheel bug (Arilus cristatus).

And “a glance” is truly all you should ever give these creatures. Wheel bugs are “assassin bugs” – members of the insect family Reduviidae – and the common name is not accidental or hyperbole. These insects bite and bite hard. In a classic example of “adding insult to injury”, assassin bugs inject specialized venom into their victims that causes vertebrates tremendous nerve pain (that would be you!).

Luckily for us, humans aren’t on wheel bugs’ menu. They are predators, and prefer to use their sharp, stabbing beaks and venom on insect prey. They are perfectly happy to leave us alone, and we should return the favor. Remember that those stabbing beaks evolved to puncture hard insect exoskeletons – soft-bodied humans pose no challenge to wheel bugs. And if we are so foolish as to handle or harass a wheel bug, we really won’t like their response.

Species Information


Common NameWheel bug
Scientific NameArilus cristatus
ClassificationClass Insecta, Order Hemiptera, Family Reduviidae (“assassin bugs”)
Size – imperial (metric)1.125-1.375 in (28-36 mm)
AppearanceBody longer than it is wide; long, thin head tipped with three-segmented beak carried underneath the body at rest; bulging eyes. Light gray to gray body, wings slightly darker than body.

Thorax is raised into a round, vertical ridge edged with jagged teeth that resembles a cogwheel (thus the common name for this species).
HabitatFound throughout North Carolina, usually in vegetation, especially meadows, farm fields, and gardens.
Common North Carolina assassin bug species
A species of assassin bug called a wheel bug (Arilus cristatus) has stabbed a fellow insect from the true bug order Hemiptera to death with its sharp beak and is sucking out the victim's liquefied inner tissues.
A species of assassin bug called a wheel bug (Arilus cristatus) has stabbed a fellow insect from the true bug order Hemiptera to death with its sharp beak and is sucking out the victim’s liquefied inner tissues. Courtesy Dan Rieck, Canva.

For information about assassin bugs and how they live, check out this Now I Wonder post “Assassin Bugs – Truth in Advertising“.


Milne, Lorus, and Milne, Margery. 1980. National Audubon Society Field Guide to Insects and Spiders North America. New York (NY): Chanticleer Press, Inc.

Eaton, Eric R., and Kaufman, Kenn. 2007. Kaufman Field Guide to Insects of North America. New York (NY): Mariner Books, HarperCollins


Christine is the creator and author of NowIWonder.com, a website dedicated to the animals and plants that share our world. Inspired by lifelong exploration and learning, Christine loves to share her knowledge with others who want to connect with wild faces and wild spaces.

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