Hickory Horned Devil Variation?
I found this little beauty while walking around our farm on a photography stroll. The reddish/plum color caterpillar was on a sweetgum. I’ve looked around the .net and found no specimens that looked like this one….excpet for the Hickory Horned Devil. Could not find one unless it was green in color, but the markings and the horns were almost identical on some of the photographs I saw. Photo taken on September 3, 2007
This is a Hickory Horned Devil in its third instar. Caterpillars go through five instars as they grow, each time shedding their skin and changing appearance. In some species the change is quite dramatic. In two more molts, your specimen will be much larger and have the characteristic blue green coloration with red horns of the fifth instar, fully grown Hickory Horned Devil. BugGuide has a nice series of images from egg to final instar.