The biara, also known at Machete Payara is a South American piscivorous fish in the dogtooth characin family. It belongs to the monotypic genus Rhaphiodon, although some minor differences in morphometrics and colour are known from across its large range. It is found in the Amazon, Orinoco, and Río de la Plata Basins, as well as rivers of the Guianas. It occurs in a wide range of freshwater habitats such as main river channels, flooded forests, lakes and reservoirs. Some populations are migratory.