Esox is a genus of freshwater fish, the only living genus in the family Esocidae—the esocids which were endemic to North America and Eurasia during the Paleogene through present. The species of this genus are known as pike and pickerel. The type species is E. lucius, the northern pike. The big pike species are native to the Palearctic and Nearctic ecozones, ranging across northern North America and from Western Europe to Siberia in Eurasia.