I accidently got my last beetle in my first game. I was training a doctor and one of my kids was sniffing the blue flower I needed to for the doctor to examine. To move the kid out of the way, I picked her up & just dropped her. To my surprise, the girl knelt down and started to pick something up. I had "accidently" dropped her on the purple w/ green dots beetle, which I'd been looking for for days. I never even saw the beetle! I was lucky.

I've now started a new game and am waiting for the uncommon all blue beetle to finish the game.