As I was driving away today at the refuge, I spotted an inch worm on my arm. So I decided to take a few photos of it. It is apparently called a common pug (Eupithecia miserulata), a moth of the family Geometridae.
Inch worms are the larvae of moths of the family Geometridae. There are over 1,200 species of inch worms native to North America. I have no idea which species this one is.