Common European sport fish (Rutilus rutilus) of the carp family (Cyprinidae), found in lakes and slow rivers. A high-backed, yellowish green fish with red eyes and reddish fins, the roach is 6–16 in. (15–40 cm) long and weighs up to 4.5 lbs (2 kg). It lives in small schools and eats plants, insects, and small animals. It is sometimes eaten or used as bait. In North America, other fishes are called roach, including the rudd, the golden shiner (both cyprinids), and several members of the sunfish family (Centrarchidae).
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