Description Myletes bidens = Piaractus brachypomus
Skull from side, Skull from above, Left mandible from back
Source
Français : Expédition dans les parties centrales de l'Amérique du Sud, de Rio de Janeiro à Lima et de Lima au Para sous la direction du Comte Francis de Castelnau , 1856. (exemplaire de la bibliothèque patrimoniale de Gray (France))
Author Francis de Laporte de Castelnau (1810–1880) https://en.wikipedia.org/wiki/Francis_de_Laporte_de_Castelnau
Source: https://commons.wikimedia.org/wiki/File:F_de_Castelnau-poissonsPl35.jpg

Piaractus brachypomus is an Amazonic pacu, a close relative of piranhas and silver dollars. As with a number of other closely related species, P. brachypomus is often referred to as the red-bellied pacu. This has resulted in a great deal of confusion about the nature and needs of all the species involved, with the reputation and requirements of one frequently being wrongly attributed to the others. An unambiguous name for P. brachypomus is pirapitinga. Order: Characiformes, Family: Serrasalmidae, Genus: Piaractus, Species: Piaractus brachypomus (G. Cuvier, 1818).