Currently viewing the category: "Hickory Horned Devil"

Subject:  Wierd looking bug appearedin my backyard
Date: 03/20/2021
Time: 01:49 AM EDT
Geographic location of the bug:  Australia, Victoria
Your letter to the bugman:  Hi! The other day this weird bug was eating my flowers so I carefully picked it up and put it on the sidewalk. Can you please try to figure out what it is?
How you want your letter signed:  Thanks, from TheBugQueen

Hickory Horned Devil: IN AUSTRALIA?????

Dear TheBugQueen,
Had you sent this email today, we would have thought for sure that you were pranking us on April Fool’s Day, but you sent this identification request in over a week and a half ago.  This is a Hickory Horned Devil, the caterpillar of the Royal Walnut Moth, but it is not native to Australia.  This species is native to eastern North America.  We have no idea how it got to Australia.  Perhaps there is a Saturniid fancier in your neighborhood who raised specimens and some escaped.  To the best of our knowledge, there are no known populations of
Citheronia regalis naturalized in Australia.  We are tagging this as a mystery.


Subject:  old pic of caterpillar
Geographic location of the bug:  Maryland, usa
Date: 07/11/2019
Time: 10:04 PM EDT
Your letter to the bugman:  While looking through old pics I had taken long ago, found a pic I took maybe in late 70s, early 80s. Never found out what it was. Any ideas? Back then I was afraid to investigate it, I was young, Now I am older and so curious
How you want your letter signed:  jackie

Hickory Horned Devil

Dear Jackie,
This spectacular caterpillar is a harmless Hickory Horned Devil.

You can disregard my question, found from a friend it is hickory horned devil caterpillar. I had searched everywhere for answers. Figures, as there were 2 hickory trees nearby at the time of the picture. Thanks anyway. Did not want to waste your time!!!!

Subject:  Unknown caterpillar
Geographic location of the bug:  East Texas
Date: 10/16/2017
Time: 10:58 AM EDT
I work at a ranch in rusk Texas and I came across this caterpillar and I’ve never seen this kind before kinda want to know what kind it is and if it is poisonous
How you want your letter signed:  Aaron

Hickory Horned Devil

Dear Aaron,
Despite its fierce appearance, the Hickory Horned Devil is perfectly harmless.  This individual has grown to its maximum size, so it left the hickory, walnut or other food tree and it is searching for a suitable place to dig beneath the surface of the ground to pupate.

Hickory Horned Devil

Thank you so much you helped a lot I let him go yesterday where I found him.

Subject:  What is this??
Geographic location of the bug:  Charleston, WV
Date: 09/06/2017
Time: 08:28 PM EDT
Just want to know what this crazy thing is. It’s in a hydrangea shrub.
How you want your letter signed:  Cynthia

Hickory Horned Devil

Dear Cynthia,
Is there a nut tree near the hydrangea???  This is a Hickory Horned Devil, one of the most distinctive looking North American caterpillars.  Early instars are brown, but as the caterpillars grow and molt, they eventually become spectacular, enormous caterpillars that are green, aqua and red, making the Hickory Horned Devil the largest North American caterpillar.  We have never heard of them feeding on hydrangea, so we suspect this individual was dislodged from a more typical food plant and is crawling around to find something to eat.  If there is a nut tree nearby, you should relocate it so it can continue to feed and eventually mature.  According to BugGuide:  “Larvae feed on leaves of ash, burning bush, butternut, cotton, gum, hickory, lilac, pecan, persimmon, sumac, sycamore, and walnut” and if it is really feeding on the hydrangea, that would be an additional food plant.  The adult Royal Walnut Moth it will eventually become is equally spectacular.

Update:  September 17, 2017
It is eating the hydrangea. There are not any nut trees nearby, except for huge oak trees.  There is a second one in another hydrangea on the other side of the porch.

Hi Daniel,
I just wanted to share a couple more photos of the caterpillars I inquired about. My mother actually discovered a second one in another hydrangea bush. They have none of the trees you listed nearby, so were not able to relocate them. However, both are eating, growing and changing colors in the hydrangeas.

Hickory Horned Devil eating Hydrangea

Thanks for the update Cynthia. We have not been able to locate any additional information on Hickory Horned Devils eating leaves from hydrangea.

Subject: What’s this caterpillar?
Location: Melrose Florida
August 19, 2017 10:10 am
Hello, I’m in Melrose Florida in a wooded area and came upon this guy on the trail. I’m curious what he is and since I can’t find a photo like him in my online searches thought you might appreciate this one. He’s about 4 inches long and 3/4 inch diameter. Beautiful creature and intimidating with all those spikes on his head.
Signature: Kimberly

Hickory Horned Devil

Dear Kimberly,
The Hickory Horned Devil is one of the largest and most impressive caterpillars in North America.  Though frightening looking, it is perfectly harmless, and those spikes are not capable of stinging.  This is our first Hickory Horned Devil sighting of the season.

Very cool! Thanks for the response. He was very beautiful!

Subject: Large caterpillar
Location: Southern AZ
August 19, 2017 10:04 am
We live in southern AZ had have these giant greenish gray (photo attachment) and tan version of this attached caterpillar on our AZ cotton. Are they the Horned devil caterpillar?
Signature: Len Nowak

Citheronia splendens sinaloensis Caterpillar

Dear Len,
You are quite observant to notice the similarities between your caterpillar and the Hickory Horned Devil, but that species is found only as far west as Texas according to BugGuide information.  Your individual looks so similar because it is a close relative in the same genus
Citheronia splendens sinaloensis, a moth with no common name.  The adult moth, which is pictured on BugGuide, is a darker, duller variation on the adult Royal Walnut Moth, the adult Hickory Horned Devil.

Citheronia splendens sinaloensis Caterpillar

Thanks Daniel
Besides the AZ horned devil….
We have amazing critters here at 4200′ in southern AZ.
A small sampling…
Signature:  Len Nowak

“Arizona Devil”

Thanks for the additional images Len.  The new “Arizona Devil” image is a wonderful addition to your previous posting.