My kids found a really weird-looking, scary bug in our backyard. It has a thing on its back that looks like a chicken’s comb, with a skinny neck and a little head. It looked like it was carrying a moth. It’s about 2 inches long. Any idea what it is? Does it bite or sting? F. H., Methuen, MA

Be Careful! Wheel Bugs Have a Fierce Bite

Adult wheel bug

Wheel bug nymph

I love listening to people try to describe this creature. What you found is probably a specimen of the wheel bug, Arilus cristatus. It gets its name because of the large, semicircular crest on its back that looks like half of a cogwheel or a saw blade with teeth.

Wheel bugs are a pretty impressive size, too, about 1-1/2 inches long. The adults are dark grayish-brown. They are found mostly in the eastern and southern states and are seen mostly on outdoor plants where their prey is found.

Wheel bugs do look rather ferocious, not just because of that impressive toothy cogwheel on their backs, but if you look closely you will see that they have beady eyes and stabbing, beak-like mouthparts. And in fact, they can give you a pretty painful bite if you try to handle one. The pain reportedly is worse than a wasp sting and can last for several hours up to several days. The skin around the bite may turn numb and eventually sloughs off.

They Belong to a Group Called “Assassin Bugs”

Both the adult and the immature bugs feed on an array of plant-feeding insect pests, so they are considered to be beneficial insects. They have somewhat enlarged front legs that they use to grab the caterpillar or other insect. They then insert their beak and drain out the victim’s body fluids. If prey is scarce, they sometimes eat each other.

In the fall, the female wheel bug lays a cluster of eggs, usually on small twigs within four feet of the ground. The eggs are said to look like miniature brown bottles with fancy white stoppers! You can also find the egg clusters on bark, fence rails, under roof eaves, and in similar places. The nymphs that will hatch out next spring are red and black with long legs.

Wheel bugs don’t require any control measures other than taking care that you don’t accidentally touch one. Carefully check any potted plants or flowers that you bring in from outside. Wheel bugs can be attracted to outdoor lights at night where they hunt prey. While they are most commonly seen in late summer and fall, you usually will only find one or two at a time.

Photo: Ragesoss (Own work) [CC-BY-SA-3.0], via Wikimedia Commons
Larva photo: By Photo by and (c)2007 Derek Ramsey (Ram-Man) (Self-photographed) [GFDL 1.2], via Wikimedia Commons