Teleostei

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iTeleostei

Yellow perch (Perca flavescens)

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Infraclass:	Teleostei

Superorders

Osteoglossomorpha
Elopomorpha
Clupeomorpha
Ostariophysi
Protacanthopterygii
Sternopterygii
Cyclosquamata
Scopelomorpha
Lampridiomorpha
Polymyxiomorpha
Paracanthopterygii
Polymyxiomorpha
Acanthopterygii

Teleostei is one of three infraclasses in class Actinopterygii, the ray-finned fishes. This diverse group, which arose in the Triassic period <ref name = Palmer>Palmer, Douglas (1999). The Marshall Illustrated Encyclopedia of Dinosaurs & Prehistoric animals. London: Marshall Editions Developments Ltd. 3-8290-6747-X.</ref>, includes 20,000 extant species in about 40 orders. The other two infraclasses, Holostei and Chondrostei, are paraphyletic.<ref name="benton">Benton, Michael J. (1990). Vertebrate Paleontology. London: Chapman & Hall. ISBN 0-412-54010.</ref>

See Actinopterygii for a complete list of orders.

[edit] Characteristics

Teleosts have a movable maxilla and premaxilla and corresponding modifications in the jaw musculature. These modifications make it possible for teleosts to protrude their jaws outwards from the mouth.<ref name="benton" /><ref>Ben Waggoner (1995-07-17). Telostei. Museum of Paleontology, University of California, Berkeley. Retrieved on 2006-06-08.</ref> The caudal fin is homocercal, meaning the upper and lower lobes are about equal in size. The spine ends at the caudal peduncle, distinguishing this group from those in which the spine extends into the upper lobe of the caudal fin. <ref name="benton" />