The beardfishes consist of a single extant genus, Polymixia, of deep-sea marine ray-finned fish named for their pair of long hyoid barbels. They are classified in their own order Polymixiiformes. But as Nelson says, "few groups have been shifted back and forth as frequently as this one, and they were recently added to Paracanthoptergii". For instance, they have previously been classified as belonging to the Beryciformes, and are presently considered either paracanthopterygians or the sister group to acanthopterygians. They are of little economic importance.
Enchodus is an extinct genus of aulopiform ray-finned fish related to lancetfish and lizardfish. Species of Enchodus flourished during the Late Cretaceous, where they were a widespread component of marine ecosystems worldwide, and there is some evidence that they may have survived to the Paleocene or Eocene; however, this may just represent reworked Cretaceous material.
Acanthomorpha is an extraordinarily diverse taxon of teleost fishes with spiny fin rays. The clade contains about one-third of the world's modern species of vertebrates: over 14,000 species.
Apateodus is a genus of prehistoric marine ray-finned fish which was described by Woodward in 1901. It was a relative of modern lizardfish and lancetfish in the order Aulopiformes, and one of a number of prominent nektonic aulopiforms of Cretaceous marine ecosystems.
Bananogmius is an extinct genus of marine ray-finned fish that was found in what is now North America and Europe during the Late Cretaceous, from the Cenomanian to the Santonian. It lived in the Western Interior Seaway, which split North America in two during the Late Cretaceous, as well as the proto-North Sea of Europe.
Aulolepis is an extinct genus of prehistoric marine ray-finned fish that lived from the middle Cenomanian to the late Turonian. It contains a single species, A. typus from the Chalk Group of the United Kingdom and the Hesseltal Formation of Germany.
Enchelion is an extinct genus of prehistoric marine ray-finned fish that lived during the Late Cretaceous. It contains a single species, E. montium known from the upper Cenomanian of the Haqel locality of the Sannine Formation in Lebanon. It is the only member of the family Encheliidae.
Ctenocephalichthys is an extinct genus of prehistoric marine ray-finned fish, generally considered a holocentriform, that lived during the Late Cretaceous. It is known from Cenomanian to the Santonian of Lebanon.
Elopopsis is an extinct genus of marine ray-finned fish that lived during the Late Cretaceous of Europe, North Africa and North America. It was a member of the Crossognathiformes, in the family Pachyrhizodontidae.
Enchelurus is an extinct genus of prehistoric marine ray-finned fish that lived during the Late Cretaceous. It contains three species, known from the Cenomanian to Campanian of Europe and the Middle East.
Lissoberyx is an extinct genus of prehistoric ray-finned fish belongon to the family Trachichthyidae. Lissoberyx is a trachichthyid, but it shows more resemblance to the holocentrids than any other trachichthyid.
Barcarenichthys is an extinct genus of prehistoric marine ray-finned fish that lived during the Late Cretaceous. It contains a single species, B. joneti, from the late Cenomanian of Portugal.
Ctenothrissa is a prehistoric genus of marine ray-finned fish in the order Ctenothrissiformes. It contains a number of species known from the Late Cretaceous of England and Lebanon.
Clupavus is an extinct genus of marine ray-finned fish that lived during the middle of the Cretaceous period. It is known from North Africa, Europe, Brazil, and possibly North America.
Dinelops is an extinct genus of marine ray-finned fish from the Late Cretaceous. It contains a single species, D. ornatus, from the Cenomanian of England. It was initially and often continues to be classified in the Osmeroididae, a family of extinct elopomorph fish that are placed in either the Albuliformes or Elopiformes. However, other studies place Osmeroides in the Albuliformes and Dinelops in the Elopiformes.
Dalmatichthys is an extinct genus of marine beardfish from the Late Cretaceous. It contains a single species, D. malezi from Croatia. It is the only member of the family Dalmatichthyidae, which is sometimes considered synonymous with Polymixiidae. Its exact relationship to modern beardfish in Polymixia likely needs further research.
The Sannine Formation, also called the Sannine Limestone, is a Cretaceous geologic formation in Lebanon. It is a Konservat-Lagerstätte that contains a high diversity of well-preserved fish, reptiles, and invertebrates from the Tethys Ocean within its three main localities: Haqel, Hjoula, and Nammoura.
Corusichthys is an extinct marine pycnodontiform that lived during the Late Cretaceous of what is now Lebanon. It contains a single species, C. megacephalus from the late Cenomanian-aged Haqel site of the Sannine Formation.
Armigatus is an extinct genus of marine clupeomorph fishes belonging to the order Ellimmichthyiformes. These fishes lived in the Cretaceous ; their fossil remains have been found in Mexico, Europe, the Middle East and North Africa, suggesting the genus ranged across the Tethys Sea.
The Akrabou Formation is a Late Cretaceous -aged geological formation and Konservat-Lagerstätte in Morocco. It overlies the slightly older freshwater deposits of the Kem Kem Group, which it was once thought to be apart of. It was deposited over following the Kem Kem ecosystem's submergence by the Tethys Ocean during a marine transgression from the Cenomanian-Turonian boundary event, as part of a wider deposition of carbonate platforms across the region from the event.
