Hydrocynus is a genus of characin fish in the family Alestidae commonly called "tigerfish," native to Africa.

The genus name is derived from Ancient Greek ὕδωρ ("water"[1]) + κύων ("dog"[1]).

The genus contains five species,[2] all commonly known as "African tigerfish" for their fierce predatory behaviour and other characteristics that make them excellent game fish.

[3] Hydrocynus are normally piscivorous,[4] but H. vittatus is proven to prey on birds in flight.

[5] The earliest fossils which have been identified as belonging to Hydrocynus are dated as Late Miocene, and have been found from the Chad, Maronga, Turkana and Semliki basins of northern and eastern Africa, in all of which Hydrocynus species still occur.