Pascual Hernandez
Pascual Hernandez

We received a question about some bugs on a tree. They were orange, big-legged creatures and plentiful. t turned out to be the nymphs (immature stage) of wheel bugs.

These are interesting bugs.

Wheel bugs are one of the largest true bugs.

Adult wheel bugs are gray and approximately one and a quarter inches long.

Its name comes from the large spiny ridge or “wheel” on the thorax (middle section) of the wheel bug’s body.

This semicircular crest is behind the head and holds 8 to 12 bulging teeth-like structures.

In the fall, females lay up to 200 tiny eggs in clusters on shrubs or tree twigs. Egg masses resemble honeycombs.

These eggs overwinter glued together by a gummy substance, and hatch the following spring into one eighth inch long wingless red and black nymphs with long legs.

They scatter onto surrounding trees and shrubs. Nymphs will undergo five molts and metamorphose into an adult by the end of summer.
Wheel bugs are beneficial predators, preying upon caterpillars, beetle larvae and adults, aphids, and other soft-bodied insects.

The wheel bug’s saliva contains a substance that paralyzes the prey within 30 seconds, dissolving their insides- it will then drain all of the prey’s bodily fluids.

Though it isn’t as strong as the stink bug’s, wheel bugs do have an odor that’s strong enough to make an impression on a potential predator.

Because of their appearance, it may seem a dangerous insect.

But, do they bother humans?

Wheel bugs are not aggressive and will avoid contact.

However, if handled, the wheel bug can inflict a painful sting.

If stung, you should wash and apply antiseptic to the site.

Treatment by a physician is not usually needed unless you experience anaphylactic reaction such as swelling or difficulty breathing.

All in all, these are beneficial insects and do not require treatment.