Monotypic prehistoric ray-finned fish genera

Amphistium paradoxum (from , 'on both sides', 'sail', and 'extraordinary'), the only species classified under the genus Amphistium and the family Amphistiidae, is a fossil fish which has been identified as a Paleogene relative of the flatfish, and as a transitional fossil. In a typical modern flatfish, the head is asymmetric with both eyes on one side of the head. In Amphistium, the transition from the typical symmetric head of a vertebrate is incomplete, with one eye placed near the top of the head.

Bawitius is an extinct genus of giant polypterid from the Upper Cretaceous (lower Cenomanian) Bahariya Formation of Egypt. The type species is B. bartheli, named as a species of Polypterus in 1984, and the genus etymology comes from Bawiti, the principal settlement of the Bahariya Oasis in Egypt. It is known from the holotype TU-B SFB 69 Vb 003 (= Bah 5/12-016): left ectopterygoid scales and some sparse scales.

Pycnodus (from , 'dense' and 'tooth') is an extinct genus of ray-finned fish from the Eocene period. It is a wastebasket taxon, although many fossils from the Jurassic or Cretaceous are assigned to this genus, only the Eocene species, P. apodus is valid. As its name suggests, it is the type genus of Pycnodontiformes. thumb|left|Proscinetes bernardi, one example of pycnodont that was once assigned as Pycnodus The known whole fossils of Pycnodus are up to long, and have a superficial resemblance to angelfish or butterflyfish. The animals, as typical of all other pycnodontids, had many knob-like

Bonnerichthys is a genus of fossil fishes within the family Pachycormidae that lived during the Coniacian to Maastrichtian stage of the Late Cretaceous. Fossil remains of this taxon were first described from the Smoky Hill Member of the Niobrara Chalk Formation of Kansas (Late Coniacian-Early Campanian), and additional material was later reported from the Pierre Shale, Mooreville Chalk, Demopolis Chalk, Wenonah Formation, and Moreno Formation, among other localities. It has also been reported in European Russia, specifically from the Rybushka Formation of the Saratov Region. It grew to at leas

Euthynotus is an extinct genus of prehistoric marine ray-finned fish that lived in Europe during the Early Jurassic epoch. It is generally considered the basalmost pachycormiform, although more recent studies instead place it as the most basal member of the predatory lineage within the pachycormiforms, the Protosphyraenidae.

Eosalmo is an extinct genus of ancient freshwater salmonid with a single described species Eosalmo driftwoodensis. The genus lived during the Eocene epoch and has been recovered from late Ypresian fossils in the Eocene Okanagan Highlands of the northwestern United States and western Canada. Additional fossils briefly mentioned as Eosalmo were reported from Russia, but they have not received close taxonomic treatment since. E. driftwoodensis is used as a phylogenetic calibration point for studies of the relationships in Salmonidae and Salmoniformes. Based on preservation of juvenile to adult sp

Eolactoria ("dawn Lactoria") is an extinct genus of highly unusual prehistoric boxfish from the Eocene. It contains a single species, E. sorbinii from the Ypresian-aged Monte Bolca site in Italy. left|thumb|Life restoration It had two pairs of long spines, one over each eye, and one pair beneath the anal and caudal fins, arranged very similarly to those possessed by the modern genus Lactoria (e.g., "cowfish"), but much longer. E. sorbinii had a fifth spine between the two eye-spines, arranged and looking very much like a nose.

Piranhamesodon pinnatomus is a pycnodontiform fish from the Late Jurassic (ca. ). It was described from the Plattenkalk deposits of the Solnhofen Formation, in Bavaria, Germany. It is notable for having sharp, serrated teeth highly reminiscent of a piranha, a highly unusual trait as most other species in the order Pycnodontiformes were shellfish eaters with flat, crushing teeth. It is also the oldest known bony fish with this trait. This unusual combination is reflected in its genus name, which is a combination of piranha and the frequent pycnodontiform genus suffix Mesodon. Fossils of other f

Sphenocephalus (from , 'wedge' and 'head') is an extinct genus of ray-finned fish that lived during the Cretaceous period. Fossils have been found in England and Italy.

Eomola is an extinct genus of ocean sunfish that inhabited the northeastern Tethys Ocean during the Eocene. It contains a single species, E. bimaxillaria from the Bartonian-aged Kuma Formation of Krasnodar Krai, Russia.

Acanthonemus (from , 'spine' and 'to distribute' or 'covered') is an extinct genus of prehistoric marine ray-finned fish that lived from the early Eocene. It contains a single species, A. subaureus (synonyms: A. bertrandi Agassiz, 1834, A. filamentosus Agassiz, 1834), known from the famous Monte Bolca site in Italy. It is the only genus in the extinct family Acanthonemidae.

thumb|left|Restoration

Gabanellia is an extinct genus of marine ray-finned fish from the Late Triassic of Italy. It contains a single species, G. agilis, from the Norian-aged Calcare di Zorzino formation.

Vomeropsis is an extinct genus of prehistoric jack fish that lived from the early to middle Eocene.

Eurycormus is an extinct genus of prehistoric marine ray-finned fish known from the Late Jurassic. It contains a single species, E. speciosus, known from the early Tithonian-aged Eichstätt Formation of Germany.

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.'''' left|thumb|Life restoration C. megacephalus is known from a 34 mm long fossil. It had plates arranged like a helmet around its head, and had a massive, triangular spine on its dorsal side. C. megacephalus is closely related the genera Trewavasia and Hensodon, as well as Coccodus''.

Ceratoichthys is an extinct genus of lookdown-like prehistoric jackfish that lived during the late Ypresian epoch, of the Early Eocene. It contains a single species, C. pinnatiformis of Monte Bolca, Italy. It and Vomeropsis are the only known members of the extinct subfamily Vomeropsinae.

Eastmanalepes (meaning "Eastman's scale) is an extinct genus of prehistoric jackfish known from the Eocene of Europe. It contains a single species, E. primaevus, known from the late Ypresian of the Monte Bolca site in Italy. It was originally described as a species of the jackfish genus Caranx, which it has a superficially similar outline to. However, it differs from Caranx, and almost all other jackfish, in that it has very large, very pronounced scutes along its lateral line. According to Bannikov, E. primaevus is probably more related to the extinct jackfish genera, Eothynnus and Teratichth

Ebenaqua (from Latin ebenus ("black") + aqua ("water"), referencing the type locality) is an extinct genus of freshwater bobasatraniiform ray-finned fish that lived during the Lopingian (late Permian) epoch of Australia. It contains a single species, E. ritchiei, known from the Changhsingian-aged Rangal Coal Measures of what is now Blackwater, Queensland, Australia. thumb|left|Ebenaqua ritchiei fossil

Absalomichthys velifer is an extinct, prehistoric manefish that lived during the Upper Miocene of what is now Southern California in the United States. Its dorsal fin was huge in comparison with living species. It is known from the Modelo Formation of Los Angeles County.

Aeduella is an extinct genus of freshwater ray-finned fish that lived during the Gzhelian (Late Pennsylvanian, Carboniferous ) and Asselian-Sakmarian (Cisuralian/early Permian epoch) ages in what is now France (Auvergne, Burgundy and Aveyron), Germany (Baden-Württemberg, Rhineland-Palatine, Saarland), Switzerland (Basel-Landschaft, Zürich) and the Czech Republic.

Archaeolepidotus is an extinct genus of prehistoric marine holostean bony fish that lived during the latest Permian or earliest Triassic in what is now Trentino-Alto Adige, Italy. It contains a single species, A. leonardii. It is among the earliest known fossil neopterygians, and is usually recovered as a semionotiform, but others recover it as a parasemionotiform.

Trewavasia carinata is an extinct pycnodontid fish in the family Coccodontidae that lived during the lower Cenomanian of what is now Lebanon. It had a large, forward-pointing horn-like spine between its eyes, and a massive stump-like spine emanating from the back of its head. T. carinata is closely related the genera Corusichthys and Hensodon, as well as Coccodus. It is named after Ethelwynn Trewavas. thumb|left|Artist's reconstruction

Ascalabos is an extinct genus of marine ray-finned fish known from the Late Jurassic Solnhofen Limestone of Germany. It contains one species, A. voithii. Some authorities synonymize it with Leptolepis.

Araripelepidotes is a genus of ginglymodian fish.

Brembodus is an extinct marine pycnodontid fish, the type genus of the family Brembodontidae. It contains a single species, B. ridens, known from the Late Triassic Calcare di Zorzino formation of Cene, Italy.

Asialepidotus is an extinct genus of prehistoric marine ray-finned fish that lived during the Ladinian stage of the Middle Triassic epoch. It contains a single species, A. shingyiensis, from Guizhou, China.

Asineops is an enigmatic genus of extinct freshwater ray-finned fish from the Eocene. It is the only member of the family Asineopidae and contains a single species, A. squamifrons, from the famous Green River Formation of Colorado, Wyoming, and Utah. It was described by Edward Drinker Cope in 1870. The name comes from the Greek for "donkey-faced".

Eozanclus ("dawn Zanclus") is an extinct genus of marine ray-finned fish, closely related to the modern Moorish idol, that lived during Eocene. It contains a single species, E. brevirostris that lived during the late Ypresian epoch in what is now Monte Bolca, northern Italy. It is one of two known fossil Moorish idols from Monte Bolca alongside Angiolinia. It differs from its living relative by having a much shorter snout.

Aetheodontus is an extinct genus of prehistoric marine bony fish that lived during the early Ladinian stage of the Middle Triassic epoch of what is now Italy and Switzerland. It contains a single species, A. besanensis.