unknown Ground Beetle identified as Pasimachus punctulatus

Help Identify this beetle, pretty please!!
Dear Bugman,
As an avid buglover since birth, I have captured and played with my fair share of creepy-crawlies. But I have never encountered such a bloodthirsy, savage critter such as this! I found him in Eastern Kentucky. He’s all black, with a purpleish blue outline around his body (one of the pictures shows this very well). I had a cage with 2 Bess Bugs (patent leather beetles) and a rather large Millipede in it, and the three seemed to be getting along fine. Then, I found this fella under a log (where I found he others) and was impressed. Since I found them all in the same place, I figured they could co-habitate. Unfortuantely, this guy must have been hunting when I found him, because the day after I put him in with the others, I went to check on them, and to my horror, BOTH Bess Bugs AND the Millipede had been cut into pieces. I swear, this sucker ate more than 4 times his own weight overnight, (each of the Bess Bugs were slightly larger than him, and the Millipede was almost 3 times his length) then proceded to bury himself in the dirt I had in the cage. From now on, I’ll be much more careful about who I room together, but please help me in identifying this little monster.. I was NOT happy that he ate my buddies! Thanks a bunch,

hi Sam,
This is some species of Ground Beetle, and we believe it is in the tribe Carabini, but we are not convinced it matches specimens posted to BugGuide in the genera Carabus nor Calosoma. It seems similar to the European Ground Beetle, Carabus nemoralis, but the elytra are different. We will contact Eric Eaton to see if her recognizes this spectacular specimen.

Update: (06/18/2008)
Hi, Daniel:
The big, fierce ground beetle is in the genus Pasimachus, and is probably Pasimachus punctulatus. They are highly beneficial predators of cutworms and other pest insects. We would love to have this image over at Bugguide, where the guide page for this species is currently without any images at all.

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