Both names V melanura, and synspillum could be considered somewhat correct, but recent DNA testing has found them both to be the same species, simply color variants.
This makes synspilla no longer valid, because the name melanura was scientifically described first, in the late 1800s, and synspillum not used until the early 1900s, making synspilla now, Invallid.
They are often called by the common name, red head cichlids, but there are another 3 or 4 Vieja that are also called redheads.
Below young melanura

Below Vieja biasciata.

To add to the confusion of common names.
There are a number of Geophagines called "red head"
There are the red head Tapajos (those in the OP photo.
But there are also the "red hump" Geo's from west of the Andes
G steindachneri, crassilabris, and pellegrini, maybe more