Acestrorhynchus falcatus
Acestrorhynchus falcatus is a species of fish in the family Acestrorhynchidae. It was described by Marcus Elieser Bloch in 1794, originally under the genus Salmo. It inhabits the Orinoco and Amazon Rivers in the regions of Suriname, Guyana, and French Guiana. It reaches a maximum total length of , and a maximum weight of .

A. falcatus feeds on finfish. It is of minor interest to commercial fisheries.