Anotodus

Anotodus Temporal range: Burdigalian-Zanclean 20.44–4.5  Ma PreꞒ Ꞓ O S D C P T J K Pg N
Tooth of Anotodus retroflexus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Subclass:	Elasmobranchii
Division:	Selachii
Order:	Lamniformes
Family:	Alopiidae
Genus:	† Anotodus Le Hon, 1871 [1]
Type species
Anotodus agassizii Le Hon, 1871 (Junior Synonym of A. retroflexus) [2]
Species
†A. retroflexus Agassiz, 1838 ( nomen conservadum ) †A. complanatus?Sismonda, 1849[ citation needed ]
Synonyms [ citation needed ]
Oxyrhina retroflexaAgassiz, 1838 Isurus retroflexus(Agassiz, 1838) Oxyrhina complanataSismonda, 1849 Anotodus agassizii? (Le Hon, 1871) Isurus retroflexa(Agassiz, 1838) Oxyrhina agassizii(Agassiz, 1838)

Anotodus (meaning "Tooth without posterior part") is an extinct dubious genus of thresher sharks that lived during the Neogene. The type species, is the A. agassizii, now considered a nomen dubium , why it was described from very fragmentary fossils, and are not sufficient to distinguish it from A. retroflexus, now considered the only valid species if Anotodus is a distinct genus. He has been found in North America, South America, Europe, and Australia. ^{[3] [4]}

A aditional species, the Oxyrhina complanata was recent reclassified in same genus and replaced as A. complanatus or A. complanata.^{[ citation needed ]} Now, recent studies classified Anotodus a invalid taxon, and potencially junior synonym of the Isurus retroflexus , an extinct mako shark. But, a recent studie of Szabó in 2021 suggered that Anotodus is a distinct genus, and very related to Thresher sharks.

Taxonomy

Oxyrhina retroflexa was named by Louis Agassiz in an 1838 illustration, ^[2] which was followed by his text description in 1843. ^{[5] [a]} Its holotype is a tooth of unknown provenance housed in the State Museum of Natural History, Karlsruhe. ^{[2] [5]} In 1871, Henri Le Hon named Anotodus agassizii for teeth from the Pliocene of Belgium, while acknowledging that it could be the same as O. retroflexa. ^[1] The former species is now regarded as a junior synonym of the latter; while some authors consider it to belong to Isurus , ^[7] it is more widely accepted as a distinct genus of alopiid. ^{[3] [4] [8]}

Notes

1. The publication dates are based on Brignon (2014). ^[6]

References

1. Le Hon, H. (1871). Préliminaires d'un mémoire sur les poissons tertiaires de Belgique. Brussels, BE: C. Muquardt. pp.  8–9.
2. Agassiz, J.L.R. (1835–1843). Recherches sur les poissons fossiles. Atlas, Tome III. Neuchâtel, CH: H. Nicolet. p.  tab. 33, fig. 10. doi: 10.5962/bhl.title.4275 .
3. Cappetta, H. (2012). Handbook of Paleoichthyology. Volume 3E. Chondrichthyes. Mesozoic and Cenozoic Elasmobranchii: Teeth. Munich, DE: Verlag Dr. Friedrich Pfeil. pp. 242–243. ISBN   978-3-89937-148-2.
4. Carrillo-Briceño, J.D.; Luz, Z.; Hendy, A.; Kocsis, L.; Aguilera, O.; Vennemann, T. (2019). "Neogene Caribbean elasmobranchs: diversity, paleoecology and paleoenvironmental significance of the Cocinetas Basin assemblage (Guajira Peninsula, Colombia)". Biogeosciences. 16 (1): 33–56. Bibcode:2019BGeo...16...33D. doi: 10.5194/bg-16-33-2019 .
5. Agassiz, J.L.R. (1837–1843). Recherches sur les poissons fossiles. Tome III. Neuchâtel, CH & Soleure, CH: Petitpierre & Jent et Gassmann. p.  281. doi: 10.5962/bhl.title.4275 .
6. Brignon, A. (2014). "The paleoichthyological and geological researches on the Permian deposits of Muse near Autun (Saône-et-Loire, France) at the beginning of the XIXth century". Bulletin de la Société géologique de France. 185 (4): 233–252. doi:10.2113/gssgfbull.185.4.233.
7. Kent, B.W. (2018). "The cartilaginous fishes (chimaeras, sharks, and rays) of Calvert Cliffs, Maryland". In Godfrey, S.J. (ed.). The Geology and Vertebrate Paleontology of Calvert Cliffs, Maryland, USA. Smithsonian Contributions to Paleobiology. Number 100. Washington, DC: Smithsonian Institution Scholarly Press. pp. 45–157. doi: 10.5479/SI.1943-6688.100 .
8. Szabó, M.; Kocsis, L.; Bosnakoff, M.; Sebe, K. (2021). "A diverse Miocene fish assemblage (Chondrichthyes and Osteichthyes) from the Pécs-Danitzpuszta sand pit (Mecsek Mts, Hungary)". Földtani Közlöny. 151 (4): 363–410. doi: 10.23928/foldt.kozl.2021.151.4.363 .

Further reading

• J. Herman. 1977. Les sélaciens des terrains néocrétacés and paléocènes de Belgique and des contrées limitrophes. Eléments d'une biostratigraphie intercontinentale. Mémoires pour Servir a l'Explication des Cartes Géologiques et Minières de la Belgique 15:1-450