Wildlife Spotting

It looks like the elytra don't completely cover the abdomen, and the antennae look like those of other carrion beetles, so I'm inclined to agree with Kristal. The head covering reminded me of pleasing fungus beetles, so if the Silphidae don't pan out, that might be a good family to investigate as well.

This looks like a carrion beetle (family Silphidae). Here's one that looks similar, though I'm not familiar with the beetles of Mongolia. http://bugguide.net/node/view/6746. Hope this helps.