In Super Mario Galaxy there is a character named Queen Bee. So the question is there a King Bee. It's strange how the kingdoms of the Mario Universe seem to be more of a Queendom. In Queen Bee's case there is a reason. A Queen Bee is a real type of bee in the real world. A male bee is called a drone. So instead of King Bee I have a better idea.
How about a boss called the Drone? Mario would have to dodge it's stingers and climb honeycomb walls. Once at the top, the Drone should fly next to Mario as Mario trys to shoot water at him. So if Super Mario Galaxy 3 ever exists, this is the the boss I would want.