Fantail goldfish

By the close of the Cretaceous, teleost fish had become the dominant fishes in both the oceans and in freshwater habitats. Teleosts are characterized by a fully movable maxilla and premaxilla (which form the biting surface of the upper jaw); the movable upper jaw makes it possible for teleosts to protrude their jaws when opening the mouth. Teleosts are also distinguished by having fully homocercal (symmetrical) tails.

Found from the surf zone to the abyssal depths of the ocean, teleosts include eels, catfish, tarpon, tuna, halibut, flounder, trout, cod, herring, salmon, and many other tasty and nutritious fish. They also include the fantail goldfish shown here.

For more detailed information on bony fish classification, try the Actinopterygii pages from the Tree of Life at the University of Arizona.

This seven-language fish dictionary is available from the Marine Research Institute of Iceland.