Salminus is the genus of dorados, large predatory characins from major South American river systems - the atlas lists Brazil, Argentina, Paraguay, Bolivia, Colombia, and Uruguay, spanning basins from the Amazon and Orinoco down to the Parana-Paraguay and Sao Francisco systems depending on the species. They are streamlined, powerfully muscled fish with a deeply forked tail and a golden-yellow cast to the body, and they rank among the largest members of the characiform order - atlas species span 46.5 up to 39.5 in, an exceptional size range for a characin genus.
Salminus is far better known to anglers than to aquarists. The golden dorado, especially S. brasiliensis, is one of freshwater fishing's celebrated game fish, prized for explosive strikes and aerial fights and a major draw for sport-fishing tourism on rivers such as the Parana; S. franciscanus, endemic to the Sao Francisco basin, carries the same common name. Adult size and predatory needs put Salminus well outside practical aquarium keeping. Conservation is mostly reassuring - three of four atlas species rated Least Concern - but one Vulnerable listing is a plausible signal of the pressure large migratory river fish face from dams and river fragmentation, since species like these typically depend on long, unobstructed stretches of river to complete their spawning runs.