|MadSci Network: Zoology|
Since you gave no size, I can only give a range of possibilities, with one likely candidate. Only a few families of Lepidoptera have "spiky" larvae- notably the Saturniidae (giant silk moths), Nymphalidae (brush-footed butterflies), Limacodidae (slug caterpillars), and some Noctuidae (millers). My guess (based in part on the orange face) is that you may have the larva of the Royal Walnut Moth, Citheronia regalis (Saturniidae), which is known as the Hickory Horned Devil. Some Saturniidae and Limacodidae have venomous spines, but the Hickory Horned Devil is harmless, despite its fearsome appearance (See: http://www.ext.vt.edu/departments/entomology/ornamentals/2-20.jpeg.) However, it is wise not to handle spiny caterpillars unless you know for sure. Reference: Covell, C. V., Jr. 1984. A Field Guide to the Moths of Eastern North America. Houghton Mifflin Co., Boston. (See Plate 1) Mitchell, R. T., and H. S. Zim. 1965. Butterflies and Moths. Golden Press, New York.
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