Kentisuchus

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Extinct genus of reptiles

title: "Kentisuchus" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["gavialoidea", "eocene-crocodylomorphs", "eocene-reptiles-of-europe", "prehistoric-pseudosuchian-genera"] description: "Extinct genus of reptiles" topic_path: "general/gavialoidea" source: "https://en.wikipedia.org/wiki/Kentisuchus" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Extinct genus of reptiles ::

| fossil_range = Early Eocene,

| image = Crocodylus spenceri fossil, Tellus Science Museum.jpg | image_upright = 1.15 | image_caption = K. spenceri fossil at the Tellus Science Museum | taxon = Kentisuchus | authority = Mook, 1955 | subdivision_ranks = Species | subdivision = *K. astrei Jouve, 2016

  • K. spenceri (Buckland, 1836) [originally Crocodylus spenceri] (type) | synonyms = *Crocodylus spenceri Buckland, 1836

Kentisuchus is an extinct genus of gavialoid crocodylian, traditionally regarded as a member of the subfamily Tomistominae. Fossils have been found from England and France that date back to the early Eocene. The genus has also been recorded from Ukraine, but it unclear whether specimens from Ukraine are referable to Kentisuchus.

Species

::figure[src="https://upload.wikimedia.org/wikipedia/commons/2/26/Kentisuchus.jpg" caption="''K. spenceri'' skull"] ::

The genus Kentisuchus was erected by Charles Mook in 1955 for the species "Crocodylus" toliapicus, described by Richard Owen, in 1849. William Buckland named "Crocodylus" spenceri on the basis of a partial skull found from the Isle of Sheppey in Kent, England. In 1888 Richard Lydekker considered "C." toliapicus synonymous with "C." champsoides and "C." arduini, named by De Zigno, and reapplied the name "C." spenceri to all of these species.Lydekker, R. (1888). Catalogue of the fossil Reptilia in the British Museum. London, pp. 60-63.

The genus name Kentisuchus was constructed only after it was realized that these specimens were clearly distinct from the genus Crocodylus and that some specimens originally assigned to "C." spenceri belonged to entirely different genera and species. "C." arduini was reassigned to the new genus Megadontosuchus in the same paper that Kentisuchus was first described in. A 2007 review of European Eocene tomistomines synonymized K. toliapicus and K. champsoides with K. spenceri.

Phylogenetics

::figure[src="https://upload.wikimedia.org/wikipedia/commons/3/37/Kentisuchus_champsoides.jpg" caption="''K. spenceri'' skull in multiple views"] ::

K. spenceri is closely related to Megadontosuchus and Dollosuchoides. An apparent close relationship between K. spenceri and Eosuchus lerichei has been used to imply that the latter species was a tomistomine, while it is now thought that Eosuchus is a basal eusuchian that lies outside the crocodilian crown group.

Below is a cladogram based morphological studies comparing skeletal features that shows Kentisuchus as a member of Tomistominae, related to the false gharial: |label1=Crocodylidae |1={{clade |1=Crocodylinae |label2=Tomistominae |2={{clade |1=Xaymacachampsa |2=Megadontosuchus |3=Kentisuchus |4=Maroccosuchus |5={{clade |1=Dollosuchoides |2={{clade |1={{clade |1=Thecachampsa |2={{clade |1=Penghusuchus |2=Toyotamaphimeia }} }} |2={{clade |1=Tomistoma cairense |2={{clade |1=Maomingosuchus |2=Tomistoma schlegelii False gharial |3={{clade |1=Gavialosuchus |2=Tomistoma lusitanicum }} |4={{clade |1=Paratomistoma |2=Tomistoma coppensi }} }} }} }} }} }} }} }}

Based on morphological studies of extinct taxa, the tomistomines (including the living false gharial) were long thought to be classified as crocodiles and not closely related to gavialoids. However, recent molecular studies using DNA sequencing have consistently indicated that the false gharial (Tomistoma) (and by inference other related extinct forms in Tomistominae) actually belong to Gavialoidea (and Gavialidae).

Below is a cladogram from a 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data that shows Kentisuchus as a gavialoid, more basal than the last common ancestor to both the gharial and the false gharial: |label1=Gavialoidea |sublabel1=(total group) |1={{clade |1={{clade |1={{clade |1={{clade |label1=Gavialidae |sublabel1=(crown group) |1={{clade |1={{clade |1={{clade |1={{clade |1={{clade |1={{clade |1={{clade |1={{clade |1=Gavialis gangeticus Gharial |2=Gavialis bengawanicus }} |2=Gavialis browni }} |2=Gryposuchus colombianus }} |2=Ikanogavialis }} |2={{clade |1=Gryposuchus pachakamue |2=Piscogavialis }} }} |2=Harpacochampsa }} |2={{clade |1={{clade |1=Toyotamaphimeia |2=Penghusuchus }} |2=Gavialosuchus }} }} |2={{clade |1=Tomistoma lusitanicum |2=Tomistoma schlegelii False gharial }} }} |2=Tomistoma cairense }} |2=Dollosuchoides }} |2={{clade |1=Maroccosuchus |2=Paratomistoma }} }} |2=Kentisuchus }} }}

Paleobiology

The close relation of Kentisuchus and Dollosuchoides, which are known from European localities that were on the mainland during the early Eocene, to Megadontosuchus, which is known from Italian localities that were once part of a Tethysian archipelago, suggests that it came to these islands after a dispersal event south from mainland Europe rather than north from Africa.

References

References

  1. (6 September 2021). "Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem". [[PeerJ]].
  2. Stéphane Jouve (2016). "A new basal tomistomine (Crocodylia, Crocodyloidea) from Issel (Middle Eocene; France): palaeobiogeography of basal tomistomines and palaeogeographic consequences". Zoological Journal of the Linnean Society 177 (1): 165–182. doi:10.1111/zoj.12357.
  3. Efimov, M. B. (1993). The Eocene crocodiles of the GUS — a history of development. ''Kaupia'' '''3''':23–25.
  4. (2011). "On a tomistomine crocodile (Crocodylidae, Tomistominae) from the Middle Eocene of Ukraine". Paleontological Journal.
  5. Mook, C. C. (1955). Two new genera of Eocene crocodilians. ''American Museum Novitates'' '''1727''':1-4.
  6. Buckland, W. (1836). ''Geology and Mineralogy Considered with Reference to Natural Theology''. 618 pp. Pickering, London.
  7. OWEN, R. 1850. Monograph on the fossil Reptilia of the London Clay, and of the Bracklesham and other Tertiary beds, part II: Crocodilia (Crocodilus, etc.). Monograph of the Palaeontographical Society, London, 50 pp.
  8. De Zigno, A. (1880). Sopra un cranio di coccodrillo scoperto nel terreno Eoceno del Veronese. ''Mem. R. Accad. Lincei, ser. 3, Cl. Sci. Fip., Mat., Nat., vol. 5'', pp. 65-72.
  9. Brochu, C. A. (2007). Systematics and taxonomy of Eocene tomistomine crocodylians from Britain and Northern Europe. ''[[Palaeontology (journal). Palaeontology]]'' '''50'''(4):917-928
  10. Piras, P., Delfino, M., Del Favero, L., and Kotsakis, T. (2007). Phylogenetic position of the crocodylian ''Megadontosuchus arduini'' and tomistomine palaeobiogeography. ''Acta Palaeontologica Polonica'' '''52'''(2):315–328.
  11. Jouve, S. (2004). ''Etude des crocodyliformes fini Crétace−Paléogène du Bassin de Oulad Abdoun (Maroc) et comparaison avec les faunes africaines contemporaines: systématique, phylogénie et paléobiogéographie.'' Ph.D. thesis. 652 pp. Muséum National d'Histoire Naturelle de Paris, Paris.
  12. Delfino, M., Piras, P., and Smith, T. (2005). Anatomy and phylogeny of the gavialoid crocodylian ''Eosuchus lerichei'' from the Paleocene of Europe. ''Acta Palaeontologica Polonica'' '''50''':565–580.
  13. (2018-05-01). "Toyotamaphimeia cf. machikanensis (Crocodylia, Tomistominae) from the Middle Pleistocene of Osaka, Japan, and crocodylian survivorship through the Pliocene-Pleistocene climatic oscillations". Palaeogeography, Palaeoclimatology, Palaeoecology.
  14. Brochu, C.A.. (2000). "New tomistomine crocodylian from the Middle Eocene (Bartonian) of Wadi Hitan, Fayum Province, Egypt". University of Michigan Contributions from the Museum of Paleontology.
  15. (2003). "True and false gharials: A nuclear gene phylogeny of crocodylia". Systematic Biology.
  16. Gatesy, Jorge. (2003). "Combined support for wholesale taxic atavism in gavialine crocodylians". Systematic Biology.
  17. (June 2007). "Evidence for placing the false gharial (''Tomistoma schlegelii'') into the family Gavialidae: Inferences from nuclear gene sequences". Molecular Phylogenetics and Evolution.
  18. (2008). "The rapid accumulation of consistent molecular support for intergeneric crocodylian relationships". [[Molecular Phylogenetics and Evolution]].
  19. Erickson, G. M.. (2012). "Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation". PLOS ONE.
  20. Michael S. Y. Lee. (27 June 2018). "Tip-dating and homoplasy: reconciling the shallow molecular divergences of modern gharials with their long fossil". [[Proceedings of the Royal Society B]].
  21. (2021-04-27). "Paleogenomics illuminates the evolutionary history of the extinct Holocene "horned" crocodile of Madagascar, Voay robustus". Communications Biology.
  22. Kotsakis, T., Delfino, M., and Piras, P. (2004). Italian Cenozoic crocodilians: taxa, timing and palaeobiogeographic implications. ''Palaeogeography, Palaeoclimatology, Palaeoecology'' '''210'''(1):67-87.

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gavialoideaeocene-crocodylomorphseocene-reptiles-of-europeprehistoric-pseudosuchian-genera