On Friday and Saturday nights I set up a white sheet illuminated by a blacklight to attract night-flying insects. This was the prize critter, a big sphinx moth. Beautiful markings, don't you think?
It was about two and a half inches long, nose to (folded) wingtips. My intrepid docent buddy Debbi B. kindly identified it as a Five-Spotted Hawk Moth, Manduca quinquemaculatus. Here's more on bugguide.net:
The larva of this moth is the Tomato Hornworm.
"Hawk moth" is just another common name for sphinx moth.
FiveSpotted Hawk MothManduca quinquemaculatusBass LakeCalifornia Tomato Hornworm