Spooky Nature: Hickory Horned Devils

Happy October! The countdown to Halloween is on, and to celebrate I’ll be featuring spooky species including birds, plants, caterpillars,

Happy October! The countdown to Halloween is on, and to celebrate I’ll be featuring spooky species including birds, plants, caterpillars, and more. First up… Hickory Horned Devils (Citheronia regalis), the larva of the Regal Moth. As assistant curator of a butterfly free-flight exhibit, I handle a lot of caterpillars on a regular basis, and I can easily say that none of them are quite as alarming on first sight as these freaky creatures.

Despite the fearsome look of these caterpillars, they are actually entirely harmless to humans.  For potential predators, though, their bright colors, huge eye-spots, and gigantic horns are a clear sign to stay away. After all, those horns look like quite a bit to swallow, and bright colors often signal toxicity in the animal world. And if that’s not enough, when disturbed these caterpillars will rear back and vibrate, creating a buzzing noise that’s startling in and of itself.

Oh, and did I mention that these caterpillars can grow up to six inches long, and get as fat as a hotdog? Their sheer size is enough to scare most people, even without the horns and spikes.

A few facts about the Hickory Horned Devil:

  • This species lives in the Eastern U.S., from New York south to Central Florida.
  • As the name indicates, the caterpillar hosts on hickory, plus walnuts, persimmon, sycamore, sweet gums and a number of other trees.
  • The caterpillar pupates underground in an earthen chamber.  They will remain there until the following spring, when they will emerge as the Regal Moth, sometimes also called the Royal Walnut Moth.
  • The adult moth is in the silkmoth family, and does not feed – it actually has no mouth parts. It will live off its stored fat reserves for a few days while it mates, and then die very quickly.
  • The Regal Moth is one of the largest moths in North America, with a wingspan of as much as 6 inches. Click here to see pictures of the gorgeous orange, brown, and yellow moth.
There are plenty of other freaky caterpillars out there (tomato hornworms and flannel moths come to mind), but these are the craziest I’ve ever personally come into contact with. What caterpillars do you find to be especially spooky? Tell us about it in the comments! (Next week: Spooky Flowers…)

Jill Staake
Jill lives in Tampa, Florida, and writes about gardening, butterflies, outdoor projects and birding. When she's not gardening, you'll find her reading, traveling and happily digging her toes into the sand on the beach.