User blog comment:PitchBlack696/Akantor/@comment-1604675-20111105193404/@comment-1431853-20111105211909

That's correct. Akantor, Tigrex, and other psudowyverns have arms that devolved from wings. Tigrex still has some wings left, which allow him to fly. Akantor's arms are nearly fully devolved, and that combined with its weight prevents it from flying.