Why do they have two names for the same fish though? that seems weird to me.
Someone discovered one, then someone discovered another group and thought enough difference existed to suggest it's a different species, so they named it as well. Then later on it was decided that they are essentially the same fish (~1990 IIRC). At this point one of those names is technically correct and the others aren't ("others" also including L. exasperatus and L. joanjohnsonae), but I'm not sure which specifically is the correct one at this point in time.

It's similar to Pseudotropheus zebra, Metriclima estherae, and Maylandia estherae, ... "Red Zebra".