It looks like Crenicichla lenticulata. Mine had the same blotch behind the gills and freckling on the face and gills. It looks like it may have some HITH, so it needs good, clean water and a variety of quality foods.
It's hard to tell if that's actually what it is. Could just be a blemish on the picture, or it could have bumped its head on something in the tank and scratched itself. Mine did that on occasion.
Still, with lents, good water quality is important.
Looks like a Lenticulata to me too. I had a wild caught that was being really nasty to all it's tankmates. I sold him to another member here and it killed all his fish in one night.
huh almost ordered 3 lents! maybe I should reconsider!