Here in Michigan these beetles are often called "June Bugs" in reference to the time of year when they appear. They can be extremely common - this one was on a bag of water soften salt pellets that I bought last week. 

I believe this is a scarab beetle in the genus Phyllophag.

This is a total of 141 stacked images, three separate stacks of 52 to 40 images each. The separate stacks were combined in Zerene Stacker and those three outputs were stacked in Photoshop CS6. Magnification was just over 5x lifesized. Pentax K3, SMC K 24 f3.5 reverse mounted on extension.