A texas, also called the Rio Grande cichlid, is Herichthys cyanoguttatum. In terms of colors they're usually very bland. I don't really like them.
A green texas, also called the Lowland cichlid, is Herichthys carpintis. These have larger irregular pearls and are usually blue/green in coloration. A super green texas is just specific strains/varieties/collection localities that shows a huge more amount of blue/green than a typical green texas, hence the 'super'. They're commonly Vontehillo or Escondido, but doesn't have to be as though they're more commonly collected from those places/offsprings of those caught in those places, there's plenty of mixed breeds around and even non-Vontehillo/Escondido can display really nice blue/green and can be called super green as well. So yeah, super green texans are really just any green texan that shows amazing colors.
Also green texans do commonly alternate between green and blue colorations when it suits them.
