The Hemidontidae are a small family of freshwater characins found in northern South America, south to the Paraná-Paraguay Basin. The larger species are popular food fish.
Hemiodontids have a streamlined body shape; many are fast-swimming, and are able to leap out of the water to escape predators. The adults of all species except Micromischodus sugillatus have no teeth on their lower jaws. Most species have a round spot on the side of the midbody and a stripe along the lower lobe of the caudal fin. The largest hemiodontids are around 50 centimetres (20 in) in length.