Heros severus are mouthbrooding severums (see my avatar). These are not. H. efasciatus has kind of become a catch-all term for everything that isn't notatus, severus, rotkeil, etc. so that's probably how you'd label these. I had a very similar female severum a few years ago -- she was mostly grey/blue with red markings and a maroon anal fin. She bred with a turquoise male and all the fry ended up looking like her when they grew up.
They may lighten up a bit if you put them over lighter substrate. One thing that will darken a severum's colors is to put it over dark or drab colored gravel.