Shirlee, leafminer larvae can get quite large, at least here anyway. Was there the tunneling in the foliage as with leaf miners?
If you find another one please take a photo so we can see what it looks like.
We have had these worms eating the foliage of our daylilies, nothing major just a few here and there. I'm not sure what kind they are. I think they are a type of cutworm but I've only found one photo of one with the redish heads that may be it. We haven't had them before this year.
.
