Vertebrate Zoology - V. M. Konstantinov 2011

Chordates
Gnathostomes
Class Osteichthyes - Subclass Actinopterygii - Superorder Teleostei - Order Pleuronectiformes

Flatfishes are bottom-dwelling fish that rest and swim on their side. Their bodies are strongly laterally compressed, and their eyes are not located on the sides of the HEAD, but shifted to a single side. They lack a swim bladder. The upper side of the fish is pigmented, while the lower side is usually white. Flounder larvae initially swim in the Water Column, but later, as they transition to a benthic lifestyle, their bodies flatten laterally and their eyes migrate to one side of the body—the "upper" side. There are about 500 known species, widely distributed in the world's oceans. In the seas of Russia, halibuts (Hippoglossus) and flounders (Limanda) are found. Flounders migrate relatively little; their movements, associated with the Selection of spawning grounds, wintering areas, and foraging, typically do not exceed 100 — 200 km. They often spawn near the coast or on banks. Fecundity is very high, reaching up to several million eggs. They feed on benthic invertebrates. They are an important target for trawl fisheries.



Last update: 13/08/2026

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