Wildlife Watching Wednesday: The Prickly IO Moth Caterpillar
By: Tom Berg
Surely everyone has seen a caterpillar at some point in their life. Caterpillars are common and they can be almost every color under the sun. Some are smooth-skinned and some are very furry-looking. Others are covered with sharp spines or spikes, and it is best to leave them alone. One particularly prickly or “spikey” caterpillar is the IO moth caterpillar.
Adult IO moths are beautiful: males have bright yellow forewings with hindwings that feature large, cool-looking eyespots that are black with a hint of blue to them. The eyespots also have a touch of white in the center. Females are similar but their forewings are reddish-brown in color.
IO moth caterpillars are very distinctive-looking, too. They are bright green and are covered with greenish-yellow spikes or spines (and even fine hairs). They also have red and white stripes on each side of their bodies. The spines and hairs are called setae, and they are very sharp and can break off from the caterpillar and cause painful stings or irritation to the skin if you touch them. Some people are more allergic to the venom from these spines than others, so it is wise to avoid touching them altogether.
The IO moth caterpillar typically grows to two inches in length (sometimes 2.5 inches). It feeds on a wide variety of plants, unlike some caterpillars which only feed on one type of plant (i.e. monarch butterfly caterpillars). IO caterpillars eat the leaves of trees like maple, willow, oak and elm, just to name a few. One of their favorites is sassafras. But they also eat grasses, clover, blackberry and many other plants.
For most people who handle an IO moth caterpillar and get stung, seeking medical help is not necessary. The sting can be painful, though, and is often compared to a bee sting. Simply remove any hairs or spines that are stuck to the skin and wash the area with mild soap and water. Swelling and itching can be minimized by applying hydrocortisone cream. If you do have a severe allergic reaction, however, call your doctor.
And next time, look but don’t touch!
Have you had a great outdoor experience? Join Global Outdoors and write a review to tell everyone about it! We’re building the home for trusted reviews of outdoor experiences, outfitters, and guides.
