Paratomistoma

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Extinct genus of reptiles

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

::summary Extinct genus of reptiles ::

| taxon = Paratomistoma | fossil_range = Middle Eocene, | authority = Brochu & Gingerich, 2000 | type_species = Paratomistoma courti | type_species_authority = Brochu & Gingerich, 2000

Paratomistoma (meaning "next to or near Tomistoma") is an extinct monospecific genus of gavialoid crocodylian. It is based on the holotype specimen CGM 42188, a partial posterior skull and lower jaw discovered at Wadi Hitan, Egypt, in Middle Eocene-age rocks of the Gehannam Formation. The skull is unfused but considered morphologically mature. Paratomistoma was named in 2000 by Christopher Brochu and Philip Gingerich; the type species is P. courti in honor of Nicholas Court, who found CGM 42188. They performed a phylogenetic analysis and found Paratomistoma to be a derived member of Tomistominae, related to the false gharial. It may have been a marine or coastal crocodilian.

Below is a cladogram based morphological studies comparing skeletal features that shows Paratomistoma as a member of Tomistominae: |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 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 Paratomistoma as an early-diverging 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 }} }}

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. Brochu, Christopher A.. (2000). "New tomistomine crocodylian from the Middle Eocene (Bartonian) of Wadi Hitan, Fayum Province, Egypt". Contributions from the Museum of Paleontology.
  3. (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.
  4. 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.
  5. (2003). "True and false gharials: A nuclear gene phylogeny of crocodylia". Systematic Biology.
  6. Gatesy, Jorge. (2003). "Combined support for wholesale taxic atavism in gavialine crocodylians". Systematic Biology.
  7. (June 2007). "Evidence for placing the false gharial (''Tomistoma schlegelii'') into the family Gavialidae: Inferences from nuclear gene sequences". Molecular Phylogenetics and Evolution.
  8. (2008). "The rapid accumulation of consistent molecular support for intergeneric crocodylian relationships". [[Molecular Phylogenetics and Evolution]].
  9. Erickson, G. M.. (2012). "Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation". PLOS ONE.
  10. 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]].
  11. (2021-04-27). "Paleogenomics illuminates the evolutionary history of the extinct Holocene "horned" crocodile of Madagascar, Voay robustus". Communications Biology.

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gavialoideaeocene-crocodylomorphspaleogene-reptiles-of-africaprehistoric-pseudosuchian-generataxa-named-by-philip-d.-gingerich