Just saw what I'm pretty sure is my first beetle! It seems rather tiny and I was afraid I had an unwelcome pest in my colony, but it does look like the pics I've seen.
The beetles emerge from their pupae stage as brownish colored then turn the darker black as they age. They are generally the size of the pupae which are about 1/2 to 3/4 of an inch long in size. At least that has been my experience.