Egertonodus

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Egertonodus
Temporal range: Oxfordian - Albian, 161–100  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Order: Hybodontiformes
Family: Hybodontidae
Genus: Egertonodus
Maisey, 1987
Species
  • Egertonodus basanus
  • Egertonodus duffini
  • Egertonodus fraasi?
Skeleton of "Egertonodus" fraasi from the Late Jurassic of Germany, whose placement in the genus has been doubted. Hybodus fraasi (fossil).jpg
Skeleton of "Egertonodus" fraasi from the Late Jurassic of Germany, whose placement in the genus has been doubted.

Egertonodus is an extinct genus of shark-like hybodont fish. It includes E. basanus from the Jurassic of Europe and North Africa and Cretaceous of North America, North Africa and Europe, and E. duffini from the Middle Jurassic of England. [1] [2] Indeterminate remains of the genus have been reported from the Early Cretaceous of Asia. [3] E. basanus is known from preserved skull material, [4] while E. duffini is only known from teeth. The genus is distinguished from Hybodus sensu stricto by characters of the skull and teeth. [5] E. basanus, the most common species, is thought to have reached 1.5 m (4 ft 11in) in length. [6] E. fraasi from the Late Jurassic of Germany, known from a poorly preserved full body fossil, was placed in Egertonodus in one study, but this has been subsequently questioned by other authors, due to strong differences in tooth morphology from the type species. [7] Fossils have been found in freshwater and lagoonal environments. [8] [3] [9]

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<span class="mw-page-title-main">Synechodontiformes</span> Extinct order of sharks

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References

  1. "†Egertonodus basanus Egerton 1845 (elasmobranch)". fossilworks.org. Retrieved 28 August 2023.
  2. "Egertonodus duffini Rees & Underwood, 2008". shark-references.com. Retrieved 28 August 2023.
  3. 1 2 Teng, Yu He; Sone, Masatoshi; Hirayama, Ren; Yoshida, Masataka; Komatsu, Toshifumi; Khamha, Suchada; Cuny, Gilles (2019-01-02). "First Cretaceous fish fauna from Malaysia". Journal of Vertebrate Paleontology. 39 (1): e1573735. Bibcode:2019JVPal..39E3735T. doi:10.1080/02724634.2019.1573735. ISSN   0272-4634. S2CID   155143419.
  4. Lane, Jennifer A. (2010-03-04). "Morphology of the Braincase in the Cretaceous Hybodont Shark Tribodus limae (Chondrichthyes: Elasmobranchii), Based on CT Scanning". American Museum Novitates (3681): 1–70. doi:10.1206/681.1. ISSN   0003-0082. S2CID   83939893.
  5. Rees, Jan; Underwood, Charlie J. (17 January 2008). "Hybodont Sharks of the English Bathonian and Callovian (Middle Jurassic)". Palaeontology. 51 (1): 117–147. Bibcode:2008Palgy..51..117R. doi: 10.1111/j.1475-4983.2007.00737.x . ISSN   0031-0239. S2CID   48229914.
  6. "Have you seen the 120 million year old shark fossil yet? See it at Dinosaur Isle". onthewight.com. 7 January 2015. Retrieved 28 August 2023.
  7. Villalobos-Segura, Eduardo; Stumpf, Sebastian; Türtscher, Julia; Jambura, Patrick L.; Begat, Arnaud; López-Romero, Faviel A.; Fischer, Jan; Kriwet, Jürgen (March 2023). "A Synoptic Review of the Cartilaginous Fishes (Chondrichthyes: Holocephali, Elasmobranchii) from the Upper Jurassic Konservat-Lagerstätten of Southern Germany: Taxonomy, Diversity, and Faunal Relationships". Diversity. 15 (3): 386. doi: 10.3390/d15030386 . ISSN   1424-2818. PMC   7614348 . PMID   36950327.
  8. Bermúdez-Rochas, David Didier (November 2009). "New hybodont shark assemblage from the Early Cretaceous of the Basque-Cantabrian Basin". Geobios. 42 (6): 675–686. Bibcode:2009Geobi..42..675B. doi:10.1016/j.geobios.2009.06.004.
  9. Turmine-Juhel, Pernelle; Wilks, Richard; Brockhurst, David; Austen, Peter A.; Duffin, Christopher J.; Benton, Michael J. (December 2019). "Microvertebrates from the Wadhurst Clay Formation (Lower Cretaceous) of Ashdown Brickworks, East Sussex, UK". Proceedings of the Geologists' Association. 130 (6): 752–769. Bibcode:2019PrGA..130..752T. doi:10.1016/j.pgeola.2019.08.003. S2CID   202904040.