Hickory Horned Devils

Hickory Horned Devils are pretty well named. After all, the discovery of this caterpillar in the wild is often heralded by the words “Oh, (insert invocation of deity) what is that thing!?!”. Most people hear those words and start backing away. It is an odd sort of person who feels their heart begin to race at those words, not with fear, but with excitement. Of course, we here at MOSI Outside are just that sort of people.

Hickory Horned Devils are the larvae of the fabulous Regal Moth (Citheronia regalis), also known as the royal walnut moth. These caterpillars can reach nearly six inches in length and widen to a girth that conjures the image of a creepy green hot dog with horns hanging from a tree. Despite the fearsome look of these caterpillars, they are entirely harmless. However, their bright colors, huge eye-spots and gigantic horns are pretty convincing to most predators. When disturbed, these caterpillars will rear back and vibrate, creating a rattle sound that is pretty surprising if you don’t know it is coming. In addition to looking toxic, their horns are probably a bit much for most predators to swallow, literally.

The adult moth is one of the largest in North America and has a brilliant orange color on their wings that seems like nothing that should occur in nature. Writers with much more skilled than I have spent countless hours describing the beauty of this species. In her 1912 work Moths of the Limberlost, Gene Stratton Porter’s account of the Citheronia Regalis spans the entirety of the 15th chapter.

Regal moths have a wide range in North American that stretches from the Northeast south to Florida and west to the Midwest and Texas. Here in West Central Florida, we are pretty close to the southern range extreme of this species. These three caterpillars were found in Plant City munching away on a low hanging branch of Hickory. This species hosts on hickory, walnuts, persimmon, sycamore, sweet gums and a number of other trees, so those are the trees to watch for this caterpillar.

Want to see a photo of the adult Regal Moth? Click here.