Aulonocara are bottom feeders with a different body shape. I'm sure this is one of the mbuna, and I think it's one of the races/subspecies/species from the Pseudotropheus tropheops complex, which is just as complicated and confusing as the genus Aulonocara.
@ThylacineAlivemacrophthalmus seems to be part of the tropheops complex, which now seems to have become genus. My Malawi book, which may be getting out of date now, says that the fish originally described as Pseudotropheus macrophthalmus was almost completely yellow, but the fish in this image does look like the macrophthalmus image on Zootierliste.