I do love these black Tiger Beetles, like tiny jaguars of the undergrowth. Shy of humans and prefering to do their hunting by night, one can still 
under leaf litter, rocks and assorted foresty debris and when found usually incites a loud "Hello" (from me, not the beetle). Quite often, these lovely black tigers have a squiggly streak of purple irridescence down their back. I don't know what it is as it is not a regular pattern nor is it on every beetle. Perhaps there is more to it than what we can see with our paltry human eyes.
This unfortunate fellow, was found by the side of the road where several roads intersect; lots of asphalt to cross on tiny legs. Good hunting in your Beetle Valhalla my stealthy friend.