If Flapdoodle is still in the vicinity, perhaps he can ID this larva I've been stumped on for a couple of years. :-)
CLOSED: Another caterpillar
This appears to be a prepupa, a caterpillar getting ready to move on to the next stage of its life. I'm going to guess - and I want to stress guess, that it might be a notodontid in the genus Heterocampa...
Thanks for your insight! When I first discovered it I thought someone dropped a fishing lure, it looked so fake.