Caterpillars With a Sting

Tussock moth caterpillar

Io moth caterpillar

I mentioned in my post about milkweed (8/21/13) that I had seen a tussock moth caterpillar feeding on the milkweed. Although it looked cute, warm and fuzzy, I warned readers to beware of this little creature. That is because its fuzzy hair can cause harm to some people. Between the hairs are sharp little barbs that can prick your skin like a needle.

A few days after seeing that caterpillar, I came across a different, but more potentially harmful caterpillar called the Io (eye-oh) moth caterpillar.  It is on a list of the Top Ten Most Poisonous Caterpillars. It too has these sharp barbs that can puncture your skin and cause an intense stinging sensation as well as inflammation for some people.

I was telling a friend how I found the Io caterpillar and picked it up to get a closer look before I knew of its infamous reputation. I told him that I had touched it, but didn’t feel any barbs sticking me. He replied, “Yeah, but did you put it in your mouth?”  I gave him a quizzical look. He then added, justifying his silly remark, “There is danger and then there is DANGER!”

That being said, their poisonous reputation needs to be put in perspective. Although their barbs can be harmful, it’s not like these caterpillars are out looking to sting anyone. They are used as defense mechanisms against potential predators like birds that may want to have them for a snack.

I don’t think any one should panic or run away in fear of these caterpillars. They are certainly worth a close, albeit, safe look. 

Tussock moth caterpillar

Tussock moth caterpillar

Tussock moth caterpillar

Io moth caterpillar with head at the lower end.

A curled up Io moth caterpillar.

A close up of the hind quarters of Io moth caterpillar. The dark brown and black features to the right of the red stripe are the rear legs of the caterpillar.