I found several of these beetles under some rather old and loose birch bark on a standing dead tree. They were clustered in the immediate vicinity of some dry fluffy-looking fruiting bodies of what I presume is some sort of slime mold. These stike me as leiodids but they are quite a bit larger that the more familiar little guys that roll themselves into a protective ball at the first sign of danger. These were either unable or unwilling to demontrate this technique for me.

This find was one of the many collateral benefits in my Forest Service-approved search for Py*tho str*ictus.