Hello
I think this is the species also called
Paratilapia sp. Fianarantsoa or sometimes "Green Face".
Fiamanga is a local name used for
Paratilapia in Southern Highlands, and has been given to different populations/species several times, so I think it can be a confusing name. I prefer to use
Paratilapia sp. Fianarantsoa

Ask Tom or Sonia if I'm right.
According to Patrick de Rham, this strain come from a pisciculture near Fianarantsoa.
I have some young from Sonia & Dave at home, they have a special head shape. Young P. sp. Andapa at the same size have a shorter snout.