P genus is characterized by round head, group predation and group feeding. Such as Natteri (red ascites tiger) and Piraya (rouge water tiger).
S genus is characterized by a sharp head, single predation and single feeding. Such as rhomboid (Black Water Tiger), long body (Allen) and Serrasalmus Manuel (New Valley Water Tiger).
According to the biological classification * * *, piranha has five attributes, namely, C is atoprion, Pristobrycon, Pygocentrus, Pygopristis and Serrasalmus.