Definition: Achiridae, also known as flatfish, refers to the order of Pleuronectiformes which contains over 500 species of fish. Included are the flounder, halibut, plaice, sole, and turbot. Flatfishes are common in both the Atlantic and Pacific, and many are important food and game fishes. Flatfishes have an unusual flattened body that is well suited to life on the bottom.
The development of the young flatfish recapitulates to some degree the probable evolutionary process. Newly hatched larvae are initially bilaterally symmetrical, but soon flatten and one eye migrates to the other side of the head. Changes occur also in the skeletal and digestive systems; adults have only one dorsal and one anal fin, both lacking spines. The top surface of the flatfish is usually colored to match the environment, and some species, especially the flounders, are able to change their pigmentation.
Flatfishes are divided into two groups: the soles, families Soleidae, Cynoglossidae, and Achiridae; and the flounders (including the halibuts and others), families Bothidae and Pleuronectidae.
The development of the young flatfish recapitulates to some degree the probable evolutionary process. Newly hatched larvae are initially bilaterally symmetrical, but soon flatten and one eye migrates to the other side of the head. Changes occur also in the skeletal and digestive systems; adults have only one dorsal and one anal fin, both lacking spines. The top surface of the flatfish is usually colored to match the environment, and some species, especially the flounders, are able to change their pigmentation.
Flatfishes are divided into two groups: the soles, families Soleidae, Cynoglossidae, and Achiridae; and the flounders (including the halibuts and others), families Bothidae and Pleuronectidae.
Also Known As: Flatfish, Sole
