''Gladioserratus'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

cow shark Cow sharks are a shark family, the Hexanchidae, characterized by an additional pair or pairs of gill slits. Its 37 species are placed within the 10 genera: '' Gladioserratus'', '' Heptranchias'', ''Hexanchus'', ''Notidanodon'', '' Notorynchus'', ...

. It contains three species: *''

Gladioserratus aptiensis ''Gladioserratus'' is an extinct genus of cow shark. It contains three species: *'' Gladioserratus aptiensis'' Pictet, 1865 *'' Gladioserratus magnus'' Underwood, Goswami, Prasad, Verma & Flynn, 2011 *'' Gladioserratus dentatus'' Guinot, Cappet ...

'' Pictet, 1865 *''

Gladioserratus magnus ''Gladioserratus'' is an extinct genus of cow shark. It contains three species: *''Gladioserratus aptiensis'' Pictet, 1865 *'' Gladioserratus magnus'' Underwood, Goswami, Prasad, Verma & Flynn, 2011 *'' Gladioserratus dentatus'' Guinot, Cappett ...

'' Underwood, Goswami, Prasad, Verma & Flynn, 2011 *'' Gladioserratus dentatus'' Guinot, Cappetta & Adnet, 2014 The authors of its description considered it to be an exclusively

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...

genus, containing species living from

Hauterivian The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous Epoch or a stage in the Lower Cretaceous Series. It spans the time between 132.9 ± 2 Ma and 129.4 ± 1.5 Ma (million years ago). The Hauterivian is preceded by the ...

to Cenomanian. Subsequently the species ''G. dentatus'' was described from the

Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretace ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan area ...

. Teeth described by Adolfssen and Ward (2015), collected from the middle

Danian The Danian is the oldest age or lowest stage of the Paleocene Epoch or Series, of the Paleogene Period or System, and of the Cenozoic Era or Erathem. The beginning of the Danian (and the end of the preceding Maastrichtian) is at the Cretace ...

Faxe Formation at

Faxe Faxe or Fakse is a town on the island of Zealand in eastern Denmark. It is located in Faxe Municipality in Region Zealand. The town is most known for the Faxe Brewery, Royal Unibrew, a relatively large brewery producing a range of beer and soft ...

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establish ...

, extend the temporal range of the genus to

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...

; according to the authors, the species ''"Notorynchus" serratissimus'' Agassiz (1843) should probably be assigned to the genus ''Gladioserratus'' as well, which, if confirmed, would further extended the temporal range of the genus to the early

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

References

{{Taxonbar, from=Q5566300 Hexanchidae Cretaceous sharks Prehistoric fish of Europe Shark genera Fossil taxa described in 2011