Question
QUESTION: We found a huge greenish-grey worm after my dog wouldn't stop barking at it. I live in the Adirondack mountains, upstate NY. I have never seen this worm before. Its definitely NOT a tomato horned worm. Its approx. 3-4 inches long with a horn on it back side and 4 horns at its head that look like little christmas trees ( with a little white at the tips) very unique! Its body is FAT, as round as a penny.

ANSWER: Sounds like the hickory horned devil. Also called the regal moth, Citheronia regalis (Fabricius), Saturniidae, LEPIDOPTERA. Hickory horned devils are found across North Carolina. Shade trees such as ash, butternut, button bush, cherry, hickory, lilac, persimmon, sassafras, sourwood, sumac, sweetgum, sycamore and walnut are commonly infested. Although each caterpillar may consume many leaves, damage is usually not severe because the worms are rarely abundant.

The fully-grown hickory horned devil is up to 4.5 inches long with a brown head, dark green body, black prolegs and numerous spines. Each body segment has four or more short, black spines around in a row around it. The two body segments toward the front have four long projections each that are brown at the base, black at the tip and which curve back. These are the "horns" that give the caterpillar its ferocious appearance and name. The "horns" are sometimes 3/4 inch long. The shiny, dark-brown pupa is about two inches long or more and is somewhat cylindrical.

Here is a web link to pictures of this caterpilar. http://www.shawnolson.net/a/1170/hickory-horned-devil.html

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QUESTION: I'm sorry but that is not what my caterpillar looks like. I will be more detailed for you, if you'd like to give it a second try :)  The head of my caterpillar ids green and large, its body is a greenish grey color, it has 4 shoots on the top of its head that are serated ( they look like little christmas trees, it has a single straight line down its back ( hard to see ) that are those little christmas tree bumps. ( the christmas tree shoots are green & white ) and the feet at pointy, not suctioncuppy. I hope this discription helps :D I am DIEING to know what it is. Thank you :D

Answer
I have looked through all the pictures of caterpillars I have access to and have come to this point. Caterpillars can be hard to describe and add to that my vision of the description and the 1000's of different caterpillars comes up with confusion on my part. A picture of the caterpillar would help very very much. IF you have one you can attach it to the question. OR e-mail it to me at [email protected].

Sorry that is about all I could do.