HICKORY HORNED DEVIL (Citheronia regalis) - ©Shawn Olson
America’s Biggest Caterpillar (about 6”, the size of a hotdog)
Citheronia regalis is an impressive creature in all stages of development. The adult moth is the largest (in mass, not wing area) north of Mexico, as are the spectacular larva and the substantial pupa.
As the caterpillars age, they feed during the day. They molt 5 times. Each instar is different, but on their sixth and final instar they become a bright green color, with huge black-tipped red horns, earning them their common name “hickory horned devils”.
They feed heavily on their host plant and can grow up to 15cm long/6 inches. Their scary appearance is purely a ruse; the spines, though prickly, do not sting, and the larva is harmless and actually one of the more easily handled of the saturniidae.
Just before pupation, the larva expels its gut and changes color from Frankenstein-green to a more fetching turquoise, the skin of the fully fed creature stretched shiny and tight. They then crawl down the host plant, where they burrow into the dirt and pupate in a well formed chamber. The pupae are dark brown/black in color, and have a relatively short cremaster. Some pupae overwinter for 2 seasons, perhaps as an adaption to variable and adverse conditions such as fires and flooding, or to maintain genetic diversity across generations.
Fact Source: http://en.wikipedia.org/wiki/Citheronia_regalis
Other photos you may enjoy:
Hawkmoth Caterpillar mimicking a snake
Io Moth Caterpillar
Turbulent Phosphila Caterpillars