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Related to Teleostei: teleost fish, Neopterygii, Teleosts


(vertebrate zoology)
An infraclass of the subclass Actinopterygii, or rayfin fishes; distinguished by paired bracing bones in the supporting skeleton of the caudal fin, a homocercal caudal fin, thin cycloid scales, and a swim bladder with a hydrostatic function.



a superorder of fish. Teleosts have a bony skeleton, amphicoelous (biconcave), vertebrae, and a skull with strongly developed ossifications. The body length ranges from 1 cm (some gobies) to 5 m (catfish, barracuda, swordfish, tuna). Cycloid or ctenoid scales with either little spines or bony plates cover the body; some teleosts are scaleless. The majority of these fish have scales without a ganoin (the ganoin is found only in the scales of fossil Leptolepoidei of the order Clupeiformes). Teleosts usually have a homocercal fin; some have a diphycercal fin. Most of the fish have a bulbus arteriosus; the most ancient (teleosts of the families Megalopidae and Albulidae) have retained the conus arteriosus.

Teleosts first appeared in the middle Triassic period. They have now reached their highest development, comprising approximately 40 orders. More than 90 percent of all modern species are included in the superorder. Teleosts are found in all bodies of water that support fish life. They are sexually dimorphic, with only a few hermaphrodites (for example, Serranus scriba). Fertilization is usually external, with the fish depositing their eggs; some species are characterized by internal fertilization and bring forth young alive (Baikal oil-fish, mosquito fish, and others). Some teleosts are herbivorous, some are carnivorous, and some parasitize other fish (the eel Simenchelys parasiticus and Stegophilus insidiosus). Almost all of the principal commercial fish belong to the superorder Teleostei, accounting for more than 98 percent of the world catch.


Berg, L. S. Sistema ryboobraznykh ryb, nyne zhivushchikh i iskopaemykh, 2nd ed. Moscow-Leningrad, 1955. (Trudy Zoologicheskogo in-ta, vol. 20.)
Berg, L. S. Ryby presnykh vod SSSR i sopredel’nykh stran, 4th ed., parts 1–3. Moscow-Leningrad, 1948–49.
Nikol’skii, G. V. Chastnaia ikhtiologiia, 3rd ed. Moscow, 1971.


References in periodicals archive ?
canicula where it was nearly 60% by weight, Teleostei comprised only about 30% by weight in S.
canicula, Crustacea were considered dominant and preferential by both QI and IRI, respectively, and Teleostei were only considered preferential according to the QI.
agassizii was based on shrimps (Caridae and Penaeidae) and small teleostei fish.
agassizii, however, in the region between Uruguay and Argentina, and observed values similar to the IRI for teleostei fish and decapods, 34.
Histological analysis demonstrated that the hepatocytes were spread out as anastomotic cords, arranged in two cellular layers and surrounded by sinusoids, similar to those found in other Teleostei.
The structure of the lateral line of the adults shows a great deal of variation in Teleostei and it has been extensively used in phylogenetic analyses.
2010b) incorporated different antioxidants for defense from the ORS's into a sperm diluent, finding positive effects on sperm viability (sperm motility, membrane integrity and lipid peroxidation) in stored semen of different teleostei fish for 72 to 120 h with uric acid and 72 h with methionine.
There is limited information on antioxidant systems in teleostei fish spermatozoa to be able to define which antioxidant is the most adequate one for semen storage.
In this survey, we searched about the abundance, distribution and mortality rates of eggs and larvae belonging to the teleostei living in Izmir Bay between the years 2008 and 2010.
Role of free neuromasts in larval feeding of willow shiner Gnathopogon elongatus caerulescens Teleostei, Cyprinidae.