Eye colors can be different with each species. It may signifies a certain territory or area it came from. From the way all the subgroups that were ID'd this was not used. It was lower jaws,pores, and later line scale counts.
Usually varies between each region, don't think it's a diagnostic trait. Different variants have different eye colors just as well as different species can. Best way to ID is get a good clear shot of the under jaw with the gills not inward and straight down on it, no angle to it. So we can see the shape of the jaw folds for and count pores.nif that doesn't work a side shot would be next to ask for.