Photographed in somewhat muted sunlight to reveal natural color. To me the base color appears to be a very dark brown, almost black.

This is a dead specimen. Somehow it got out of its container and wound up on the bathroom rug where I stepped on it in my sock feet. Presuming it to be dead I arranged both antennae like the right one and covered it with silica gel crystals to help it dry faster. Several days later I removed it from the dessicant and its antennae were in the present position. I suspect the beetle had enough life left in it to wiggle around some before it died and dried.