Tometes

Tometes
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Characiformes
Family:	Serrasalmidae
Genus:	Tometes Valenciennes, 1850
Type species
Tometes trilobatus Valenciennes, 1850

Tometes is a genus of fish in the family Serrasalmidae found in fast-flowing rivers in northern South America. Adults of all six species in this genus are phytophagous, feeding primarily on aquatic plants in the Podostemaceae family.

The genus name Tometes was coined in 1850 by Valenciennes in reference to the incisiform teeth. When the type species of the genus, T. trilobatus, was described in 1850, it was placed in synonym with Myleus setiger, the type species of the genus Myleus, which is why Tometes and Myleus were considered to be the same genus for a long time. It was just later that the two genera were revalitated and other specimen could be categorized in the genus Tometes.

Even today the taxonomic classification of the Serrasalmidae is not an easy task. Many names are placed in synonymy due to a lack of information and insufficient data bases. It was not long ago when it was discovered that Tometes and Myleus are two different genera but that Tometes, Myleus, Mylesinus and Ossubtus share a common ancestor. Typical characters of Tometes coincide with Mylesinus and Ossubtus specimen more than Myleus. It is further known that Tometes live in sympatry with other reophilic Serrasalmidae.Tometes species are also not to be mistaken with pacus, a vegetarian fish, which is often sold as a vegetarian piranha in the corresponding countries. One can easily distinguish one from another by their very different composition of their dentition.

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Wikipedia