Chondrostoma (from the Ancient Greek roots χόνδρος (khondros, “lump”) + στόμα (stoma, “mouth”) = “lump-mouth”) is a genus of ray-finned fish in the family Cyprinidae. They are commonly known as nases, though this term is also used locally to denote particular species, most frequently the common nase (C. nasus). The common name refers to the protruding upper jaw of these fishes; it is derived from the German term Nase, meaning "nose."
It is commonly described as a native species in Slovenia rivers and canals, as for example in the Sava. By its close colours, fins and shape, it can be confused with the common roach (Rutilus rutilus).