This species is frequently mistaken for the similar-looking congener M. spechti Schreitmüller 1936, which is easily-identified by the absence of reddish pigmentation in the dorsal, anal, and caudal fins. There has been some debate as to whether these two represent the same taxon, however, with Winstanley and Clements (2008) proposing that M. erythropterus be considered a synonym of M. spechti because they were unable to separate the two species by morphological characters, and specimens with red pigmentation on the unpaired fins were coll…