What is the species of a pirahna?

There is supposedly 25 species of pirahna. Red pirahna, red bellied pirahna, red eyed pirahna, black shoulder/ ear pirahna, cariba pirahna(wich is the same as the black shoulder/ ear), piraya pirahna, black pirahna or rhom, gold pirahna or spilo, elongated or pike pirahna, brandtii pirahna, manuel's pirahna, geryi or violet line pirahna and compressus pirahna.