Identify this caterpillar

Can you help me identify this caterpillar from southern Ontario?
Also, is there a way to keep it so that we can watch it change into a butterfly?


My money is on some kind of hawkmoth. Did you find it on a plant or tree? If you know what it eats, keeping it is a fairly simple matter of putting it in a big, well - ventilated container (such as an fishbowl covered with wire mesh) and giving it fresh leaves from the food plant every day. Make sure the container you keep it in isn’t somewhere it will fill up with rain or get overheated by direct sun.

When it’s done eating (which looks like it could be quite soon), it will pupate and it might stay in the pupa for weeks or months, then emerge as a moth or butterfly - the problem here is that you’ll have to accept one of the following:
-Check the container daily to see if it has emerged, observe it for a short while, then release it.
-Leave the container open so it can escape once it emerges
-Keep the lid on the container and accept that it might emerge and die before you notice and release it.

It doesn’t look like any hawkmoth caterpillar that I can find but I’ll take it as a possibility.
If this were a bird or flower question there would be tons of posts.
What are ya, prejudice?

I’m guessing that it is a Proserpinus fecalturdiata commonly known as the Stool Sphinx. Did you find it anywhere near your toilet?

Actually, you’re probably right - hawkmoth caterpillars tend to be a bit more showy than that and they often have a tail or spikes. Still, it looks more ‘moth’ than ‘butterfly’ to me.

Try providing a bit more information; where did you find it? Is there any evidence of what it might have been eating? What sort of landscape are you surrounded by?

It’s looking quite similar to a cutworm in many of my searches.

We found on the front steps. We have not seen it eat anything. We put it in a bug cage and it seems to have made a sort of cocoon by binding two leaves together.
We’ll see what happens. What time frame should we be looking at before it emerges?

My personal reference is a 2000 printing of the National Audubon Society Field Guide to North American Insects and Spiders, and whilst it has a section on caterpillars, it doesn’t have yours.

Good luck.