You can't say Miss BumBum didn't go out with a bang -- the final contest ever ended with 2 chicks fighting onstage over whose ass is fake ... naturally.
Brazil's annual ass competition pageant went down Monday night and 31-year-old Ellen Santana, repping hard for northern Brazil, took the top prize -- but right after she got the winner's sash, the ass attacks began.
You gotta see how Aline Uva, straight outta south Brazil, charged at Ellen, ripped off her sash and put it on herself ... all while accusing Ellen of having a surgically enhanced ass. Aline claims she has the ONLY natty cheeks in the whole contest.
Not that you care about any of that crap -- just click through the gallery, and decide for yourself if Aline's got a point.
This was, allegedly, the final BumBum pageant ever.