Scardinius is a genus of ray-finned fish in the family Cyprinidae commonly called rudds. Locally, the name "rudd" without any further qualifiers is also used for individual species, particularly the common rudd. The rudd can be distinguished from the very similar roach by way of the rudd's upturned mouth, allowing it to pick food items such as aquatic insects from the surface of the water with minimal disturbance.
