Protandry is known from some Indo-Pacific Sparidae, Muraenidae and Platycephalidae; you may wish to consult the following references:
Lee, M.-F., Huang, J.-D. & Chang, C.-F. 2008 Development of ovarian tissue and female germ cells in the protandrous black porgy, Acanthopagrus schlegeli (Percigformes: Sparidae). Zoological Studies 47 (3): 302-316.
Sen, S.-C., Lin R.-P. & Liu, F. C.-C. 1979. Redescription of a protandrous hermaphroditic moray eel (Rhinomuraena quaesita Garman). Bulletin of the Institute of Zoology, Academia Sinica 18 (2): 79-87
Shinomiya, A., Yamada, M. & Sunobe, T. 2003. Mating system and protandrous sex change in the lizard flathead, Inegocia japonica (Platycephalidae). Ichthyological Research 50: 383-386.
Thanks a lot Ronald. I finally found a species inhabiting South West Coast Atlantic Ocean, a Sparidae Diplodus argenteus :
GS David, R Coutinho, I Quagio-Grassiotto & JR Verani. 2005. The reproductive biology of Diplodus argenteus (Sparidae) in the coastal upwelling system of Cabo Frio, Rio de Janeiro, Brazil. pages 439-447