Istiophoriformes

Istiophoriformes are an order of bony fish which is not fully recognized by some taxonomists, with some including the two extant families Xiphiidae and Istiophoridae, and others, including the family Sphyraenidae.

The earliest fossils of this group are of early billfish from the Late Paleocene of Peru and Turkmenistan.

Families
The following families are classified under the Istiophoriformes. Three are extant, and three are extinct:


 * Sphyraenidae (barracudas)
 * Billfish (sometimes placed in the superfamily Xiphioidei)
 * Xiphiidae (swordfish)
 * Istiophoridae (marlins, spearfish and sailfish)
 * †Hemingwayidae
 * †Palaeorhynchidae
 * †Blochiidae