Each spring a type of beetle hatches that seems to live in our Maple trees. Looks like something prehistoric, but is completely harmless. They do come into our house though and I'm looking for a "natural" repellent to keep them out.
Could be the boxelder bug, a true bug, not a beetle, but often confused with beetles. These insects develop on maple trees and migrate to homes in the fall. See http://www.livingwithbugs.com/boxelder.html for a photo of the adult bugs. Unfortunately there are no repellents, natural or synthetic, for these bugs.