For European chubs other than this particular species, see Squalius.The chub (Squalius cephalus) is a European species of freshwater fish in the carp family Cyprinidae. It frequents both slow and moderate rivers, as well as canals and still waters of various kinds. In North America, this species is referred to as the European chub. Other names used for the species include round chub, fat chub, chevin, and pollard.