You may be wondering what an owlet caterpillar is, since “owlet” is not mentioned in some books about insects. It is a general name for moths in the family Noctuidae and is nicely defined by Marshall (2006) as: “nocturnal moths are sometimes called owlet moths (noctua means owl in Latin) because of the way their eyes pick up and reflect the smallest amount of light, shining brightly in contrast with the usually inconspicuous body and forewings”.
"Owlet Caterpillars of Eastern North America. David L. Wagner, Dale F. Schweitzer, J Bolling Sullivan & Richard C. Reardon. 2011. Princeton University Press, 576 pp., soft cover, 8 by 10.,"
The Great Lakes Entomologist, vol 45
Available at: https://scholar.valpo.edu/tgle/vol45/iss1/12