
I edited the pic to help, with details.
Below left most Cichlasoma, Aequidens, and in many other S Americans, the caudel spot sits on the upper half/portion of the caudal peduncle.
In the lone pi provided, it appears more centered above, adding to confusion.


Cichlasoma dimurus above left.
A young member of Geophagus braziliensus complex above right
Above, Gymnogeophagus balzani to compare, but I don't think so
at this tender age there are too many ID options
Could even be one of genus Thorichthys, or Cribroheros
