perch (redirected from square perch)

perch, common name for some members of the family Percidae, symmetrical freshwater fishes of N Europe, Asia, and North America. The perch belongs to the large order Perciformes (spiny-finned fishes) and is related to the sunfishes and the sea basses. Best known is the yellow (also called red) perch (Perca flavescens), a popular game and food fish abundant in lakes and large streams, where it feeds on insects, crayfish, and small fish and grows to an average length of 1 ft (30 cm) and weight of 1 lb (.5 kg). The voracious walleye, or walleyed pike (Stizostedion vitreum), another member of the family, is darker and larger (up to 10 lb/4.5 kg). Very similar to the walleye but slenderer and smaller is the Eastern sauger, or sand pike (S. canadense). The native American darters (2–3 in/5–8 cm), found E of the Rockies, are a subfamily containing many species, most of them brilliantly colored. Of separate families are the pirate perch, a chubby little fish of sluggish streams and bayous (family Aphredoderidae), and the trout perch, or sand roller, a small fish abundant in the Great Lakes (family Mugiloididae). Perches are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Perciformes, family Percidae.

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perch

Either of two species (family Percidae, order Perciformes) of popular food and sport fishes: the Eurasian common perch (Perca fluviatilis) or the North American yellow perch (P. flavescens). Some consider the two a single species. Both have one spiny and one soft-rayed dorsal fin. Perches are carnivores of quiet ponds, lakes, streams, and rivers. The common perch is greenish, with dark vertical bars on the sides and reddish in the lower fins. It grows to 6 lbs (3 kg), rarely more. The yellow perch, similar but yellower, grows to about 15 in. (40 cm) and weighs up to 2 lbs (1 kg); it is a popular game fish. See also sauger, sea bass, walleye.