There are multiple red headed (or shouldered, if you prefer) severum types, some rivaling or even surpassing rotkeils. Not all of them are even efasciatus, not to mention efasciatus sp. rotkeils, and to me the 'correct' identity can be confusing, especially considering science hasn't sorted them all out and I've also seen what are clearly different fish called by the same location name. But sp. rotkeils, from Peru, are easy, to me the easiest red headed severum to distinguish by the 8 bars. My take is that, since they haven't been scientifically described yet, you could say this is unofficial, but it's what you see (or what I've seen) in photos and book illustrations specifically describing sp. rotkeil from Peru. I bred rotkeils for a while and always got 8 bars.
Aside from the bars, you be hard pressed to distinguish young rotkeils from common green severums until the rotkeil color comes in, small ones don't have it and development of the red is a gradual process ime.
With the variability of different wild populations, severums have turned out to be more complicated than they used to be.