The above link should answer your questions. Basically long ago when midas(citrinellus) and red devils(labiatum) were imported into the country people thought they were so similar that they crossed them. So pretty every "red devil" or "midas" bought from a LFS is a cross between the two because of that. The standard rule is unless you buy from a very reputable source then you are to assume that your fish is a hybrid of both regardless of the characteristics it may display. Midevils can show strong characteristics of both a midas or a red devil but that does not mean it is either or.
By the way nice looking fish you have there he looks like a beast.
after i posted i saw that thread...opps lol, and yea he is about 7 inches. never saw a hump like that on anything but a flowerhorn. so its safe to say its a midevil? btw picked it up for 15 bucks. been an lfs nearby for 5 months.... he was like just take this fish because it keeps biting my employees.. lol it has drawn blood on many different occasions. trying to tame hime down a little.