Keaton (キートン,Keaton?) is the blue Mechaniloid enemy created by Generator Cannon. It appears in groups of three, all of which make a mad dash straight for Zero, flying even faster than Mellnets.
There is also an enemy named Keaton in the Legend of Zelda series, a serie created by Nintendo, but Capcom worked in four games of the games of the series. Whether this naming was supposed to be intentional or not is unknown, but the possibility of a coincidence is supported by the fact that the appearances of the two are different.