Ganoessus is an extinct genus of prehistoric marine herring that inhabited the coast of western North America during the Miocene. It contains three species, all known from the Upper Miocene of California, US.
The following species are known:
It was a relatively large fish with coarse, enameled scales. Its morphology, including well-developed abdominal scutes, may potentially suggest a relationship to the Alosidae, but this is uncertain.