The wonderful people on
BugGuide.com have identified both the mysterious caterpillar and the beautiful moth I posted about earlier this week.
The caterpillar is a Common Buckeye, more formally known as
Junonia coenia , who will one day look like this!

while the beautiful moth is a female Sphinx moth, also know as
Eumorpha achemon. Just to be fair, I copied this picture of the Sphinx caterpillar, quite a bold pattern, but the brown color is not so exciting.