At this present time, I am dubious as to what constitutes a BB. I suspect there are three possibilities. First, BB gets as big as yarelli and rutilus and is what is called "Thai yarelli". Second, BB is often a misidentified baby rutilus. Rutilus' famous colors don't develop until they get ten inches or so, as was so wonderfully illustrated by Estarego8's rutilus in that long ass thread. Finally, BB is in fact a dwarf species which is sympatric with rutilus and another, larger species that is as yet undescribed, which is quite possible.