Technically known as Acraga coa, and first characterized by William Schaus in 1892. I can only imagine him stumbling upon one of these – I wonder what the vernacular of the day was for “Holy Sh*t!”

As well, this is the cristal stage before it grows up to be a moth. Which, apparently, means it will one day look like this:

Caterpillar image via Project Noah. Moth image by David Brownwell, via Whatisthatbug. Also via boingboing.net.