in this video at 1:10 you can see my BA's when I got them, there is no black spot in the midline at this time but some strong horizontal barring with vertical barring. In it you can see a few of the Blue acara have the horizontal bar that runs all the way to the black spot at the tail, which ryansmith was talking about earlier, however there are others where the horizontal bar trails upwards towards the dorsal fin instead, which led to my comment of wondering if farm raised fish have changed in genetics or that BA's have just become hybrids.
I've got several videos documenting them and their changes over the last year before I rehomed them showing atypical forms or just growing in to some frankly odd shapes that no fish should look like unless screwed up genetics wise.(2 of the 6- the other 4 grew in to quite round torpedoes full of aggression you'd be more likely to see in a festae)
[video=youtube;yIm2Dwrc8jc]https://www.youtube.com/watch?v=yIm2Dwrc8jc[/video]