Eomesodon

Eomesodon
Temporal range: Early Jurassic
Potential Late Triassic, Middle Jurassic, and Early Cretaceous records
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Pycnodontiformes
Genus: Eomesodon
Woodward, 1918
Type species
Pycnodus liassicus
Egerton, 1854
Other species

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Eomesodon (Greek for "dawn Mesodon", Mesodon being a now-disused pycnodont genus) is an extinct genus of prehistoric marine pycnodont fish.[1][2]

It contains only a single definitive species, E. liassicus (Egerton, 1854) from the Early Jurassic (Hettangian to Sinemurian) of England (Lower Lias), France, and Belgium (Marnes de Jamoigne Formation). The specimen from England is known from a nearly complete skeleton.[2][3] E. liassicus is the only known species of pycnodont known from the earliest Jurassic Europe following the Triassic-Jurassic extinction event, and the group does not see further diversification in Europe until the Toarcian.[4]

In addition to E. liassicus, several other disputed species are known from earlier (Late Triassic) and much later (up to the earliest Cretaceous). However, the status of these species and their placement within Eomesodon is disputed, and later studies refer to them as "Eomesodon". If the Triassic species actually did belong to this genus, then Eomesodon would be the only pycnodont known from both sides of the Triassic-Jurassic boundary.

The following disputed species are known:[5]

  • "E." barnesi (Woodward, 1906) - latest Jurassic (Tithonian)/earliest Cretaceous (Berriasian) of England (Purbeck Group). Nearly complete specimen known.
  • "E." depressus Woodward, 1916 - Tithonian/Berriasian of England (Purbeck Group)

Some studies have found it to be potentially related to the Triassic genus Brembodus, while others have found it to be more basal.[8]

See also

References

  1. ^ Sepkoski, Jack (2002). "A compendium of fossil marine animal genera". Bulletins of American Paleontology. 364: 560. Archived from the original on 2011-07-23. Retrieved 2009-02-27.
  2. ^ a b Woodward, Arthur Smith (1895). Catalogue of the Fossil Fishes in the British Museum (Natural History). Taylor & Francis.
  3. ^ "PBDB Taxon". paleobiodb.org. Retrieved 2025-01-10.
  4. ^ Stumpf, Sebastian; Ansorge, Jörg; Pfaff, Cathrin; Kriwet, Jürgen (2017-07-04). "Early Jurassic diversification of pycnodontiform fishes (Actinopterygii, Neopterygii) after the end-Triassic extinction event: evidence from a new genus and species, Grimmenodon aureum". Journal of Vertebrate Paleontology. 37 (4): e1344679. Bibcode:2017JVPal..37E4679S. doi:10.1080/02724634.2017.1344679. ISSN 0272-4634. PMC 5646184. PMID 29170576.
  5. ^ Palaeontographical Society. Palaeontographical Society. 1918.
  6. ^ "PBDB Taxon". paleobiodb.org. Retrieved 2025-01-10.
  7. ^ Hornung, Thomas; Kogan, Ilja; Moosleitner, Gero; Wolf, Gerhard; van der Wielen, Joop (2019-12-01). "The Norian fish deposits of Wiestal („Seefeld Member", Northern Calcareous Alps, Salzburg, Austria) – taxonomy and palaeoenvironmental implications". Austrian Journal of Earth Sciences. 112 (2): 125–165. doi:10.17738/ajes.2019.0008. ISSN 2072-7151.
  8. ^ Poyato-Ariza, Francisco; Wenz, Sylvie (January 2002). "A new insight into pycnodontiform fishes". Geodiversitas. Retrieved 10 November 2023.