Observation notes: These are not the same individual, but they are the same species. I have seen 4 of this type of caterpillar pupate this week. I did not see them feeding on any host plant. First one pupated on a phlox plant, second one on the timber edge of the same flower bed. Plants in the bed are day lily, asian lily, shasta daisies, lemon thyme, sedum, vinca, artemesia. Third one pupated on a garbage can (this one is the pupa in the photo), and the fourth one is getting ready to pupate under a drain pipe. No plants near the last two. The weather has been wet and cool in this region.