These are quite common in central Oklahoma and I've raised several of them. They are a smaller sphinx moth, larger than the clearwings, but smaller than the Manducas. Different tribes, but for size comparison only.

The larvae I find here have red markings, but I have read that most don't exhibit that characteristic. I also find them on Pecan, which is not mentioned most places as a larval host. Same family, though, Juglandaceae.

The adult moths do not feed either, so won't be found flying around flowers at night.

Interesting sphinx, IMHO.

Susan

Very interesting!!