Dwardius

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Dwardius
Temporal range: Cretaceous
NHMUK PV OR 39053.png
Associated teeth of D. woodwardi (NHMUK PV OR 39053) from Cretaceous chalk in Kent, England
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Lamniformes
Family: Cardabiodontidae
Genus: Dwardius
Siverson, 1999

Dwardius is an extinct genus of cardabiodontid [1] sharks which existed during the Cretaceous period in what is now Australia, England, [2] France, and India. It was described by Mikael Siverson in 1999, [3] as a new genus for the species Cretalamna woodwardi, which had been described by J. Hermann in 1977. [4] Another species, D. siversoni, was described from the middle Albian of northeastern France by V.I. Zhelezko in 2000; the species epithet honours the author of the genus. [5] A new species, D. sudindicus, was described by Charlie J. Underwood, Anjali Goswami, G.V.R. Prasad, Omkar Verma, and John J. Flynn in 2011, from the Cretaceous Karai Formation of India. [6]

Contents

Species

Related Research Articles

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<span class="mw-page-title-main">Lamniformes</span> Order of sharks

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<i>Ptychodus</i> Extinct genus of sharks

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<i>Cardabiodon</i> Extinct genus of sharks

Cardabiodon is an extinct genus of large mackerel shark that lived about 95 to 91 million years ago (Ma) during the Cenomanian to Turonian of the Late Cretaceous. It is a member of the Cardabiodontidae, a family unique among mackerel sharks due to differing dental structures, and contains the two species C. ricki and C. venator. Cardabiodon fossils have been found in Australia, North America, England, and Kazakhstan. It was likely an antitropical shark that inhabited temperate neritic and offshore oceans between 40° and 60° paleolatitude, similar to the modern porbeagle shark.

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<i>Cretalamna</i> Extinct genus of sharks

Cretalamna is a genus of extinct otodontid shark that lived from the latest Early Cretaceous to Eocene epoch. It is considered by many to be the ancestor of the largest sharks to have ever lived, such as Otodus angustidens, Otodus chubutensis, and Otodus megalodon.

<i>Palaeocarcharodon</i> Extinct genus of sharks

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Cardabiodontidae is an extinct family of lamniform sharks. Confirmed members of this family include Cardabiodon and Dwardius, both which are genera which existed in Australia, North America, and Europe during the Late Cretaceous period. It has been suggested that Parotodus could also belong to this family, but the authors that originally made this proposal expressed a weakening of rationale for it.

<i>Archaeolamna</i> Extinct genus of sharks

Archaeolamna is an extinct genus of mackerel sharks that lived during the Cretaceous. It contains three valid species which have been found in Europe, North America, and Australia. While it is mostly known from isolated teeth, an associated set of teeth, jaws, cranial fragments, and vertebrae of A. kopingensis is known from the Pierre Shale of Kansas. Teeth of A. k. judithensis were found with a plesiosaur skeleton with bite marks from the Judith River Formation of Montana. It was a medium-sized shark with an estimated total body length of 3–4 metres (9.8–13.1 ft).

<i>Kenolamna</i> Extinct genus of Cretaceous Mackerel Shark

Kenolamna is an extinct genus of mackerel shark from the Cretaceous period known only from isolated teeth. It is named in honor of Kenneth McNamara, former curator of Paleontology at the Western Australian Museum. It is tentatively placed in the family Otodontidae, and is closest in design to Cretalamna and Paleocarcharodon though it is unclear how closely related it is to either. Currently, it is a monotypic genus containing only the species K. gunsoni.

<i>Protosqualus</i> Genus of dogfish shark that existed during the Cretaceous

Protosqualus was a genus of dogfish shark that existed during the Cretaceous. Fossils have been found in Europe, East Asia, Antarctica, Australia, India and South America. The type species is Protosqualus sigei, which was found around an Albian aged deposit in France. There are 6 species which can be differentiated by distinct features in their teeth. Some species show some level of heterodonty, for example Protosqualus barringtonensis shows a rather high level of heterodonty within its teeth. The oldest specimens are from the Speeton Clay Formation. Protosqualus teeth are quite common in the Grey Chalk deposit of England. The genus went extinct at the end of the Cretaceous during the Cretaceous–Paleogene extinction event, with the last species in the genus being Protosqualus argentinensis from southern Argentina as well as possibly being from earlier deposits in India.

References

  1. Mikael Siverson; Marcin Machalski (2017). "Late late Albian (Early Cretaceous) shark teeth from Annopol, Poland". Alcheringa: An Australasian Journal of Palaeontology. 41 (4): 433–463. Bibcode:2017Alch...41..433S. doi:10.1080/03115518.2017.1282981. S2CID   133123002.
  2. Page 148, Dinosaurs in Australia: Mesozoic Life from the Southern Continent, by Benjamin Kear, Robert Hamilton-Bruce. Csiro Publishing, 2011. ISBN   0643102310/ ISBN   9780643102316
  3. Siverson, M. 1999. A new large lamniform shark from the uppermost Gearle Siltstone (Cenomanian, Late Cretaceous) of Western Australia. Transactions of the Royal Society of Edinburgh: Earth Sciences 90: 49–66.
  4. Hermann, J., 1977. Les Sélaciens des terrains néocrétacés & paléocènes de Belgique & des contrées limitrophes. Eléments d'une biostratigraphie intercontinentale. Toelicht. Verhand. Geologische en Mijnkaarten van België, n°15, 450 pp.
  5. Zhelezko, V.I. [Železko, V.I.] 2000. The evolution teeth system of sharks of Pseudoisurus Gluckman, 1957 genus—the biggest pelagic sharks of Eurasia [in Russian]. In: B.I. Čuvašov (ed.), Materialy po stratigrafii i paleontologii Urala 4, 136–141. Izdatel'stvo Uralskogo Otdeleniâ Rossijskoj Akademii Nauk, Ekanterinburg.
  6. C. J. Underwood, A. Goswami, G. V. R. Prasad, O. Verma, and J. J. Flynn. 2011. Marine vertebrates from the ‘Middle’ Cretaceous (Early Cenomanian) of South India. Journal of Vertebrate Paleontology 31(3):539-552