Extinct genus of reptiles
Paratomistoma Tomistoma extinct monospecific genus ofgavialoid crocodylian . It is based on theholotype specimenCGM 42188, a partialposterior skull and lower jaw discovered atWadi Hitan ,Egypt , inMiddle Eocene -age rocks of theGehannam Formation . The skull is unfused but consideredmorphologically mature.Paratomistoma was named in 2000 by Christopher Brochu andPhilip Gingerich ; thetype species isP. courti in honor of Nicholas Court, who found CGM 42188. They performed aphylogenetic analysis and foundParatomistoma to be aderived member ofTomistominae , related to thefalse gharial . It may have been a marine or coastal crocodilian.[ 2]
Below is acladogram basedmorphological studies comparing skeletal features that showsParatomistoma as a member of Tomistominae:[ 3]
Based on morphological studies ofextinct taxa , the tomistomines were long thought to be classified ascrocodiles and not closely related togavialoids .[ 4] DNA sequencing have consistently indicated that thefalse gharial (Tomistoma ) (and by inference other related extinct forms inTomistominae ) actually belong toGavialoidea (andGavialidae ).[ 5] [ 6] [ 7] [ 8] [ 9] [ 10] [ 11]
Below is acladogram from a 2018tip dating study by Lee & Yates simultaneously usingmorphological , molecular (DNA sequencing ), andstratigraphic (fossil age) data that showsParatomistoma as an early-diverginggavialoid , morebasal than thelast common ancestor to both thegharial and thefalse gharial :[ 10]
^ Rio, Jonathan P.; Mannion, Philip D. (6 September 2021)."Phylogenetic analysis of a new morphological dataset elucidates the evolutionary history of Crocodylia and resolves the long-standing gharial problem" .PeerJ 9 e12094.doi :10.7717/peerj.12094 PMC 8428266 PMID 34567843 . ^ Brochu, Christopher A.; Gingerich, Philip D. (2000)."New tomistomine crocodylian from the Middle Eocene (Bartonian) of Wadi Hitan, Fayum Province, Egypt" (PDF) .Contributions from the Museum of Paleontology .30 (10):251– 268. ^ Iijima, Masaya; Momohara, Arata; Kobayashi, Yoshitsugu; Hayashi, Shoji; Ikeda, Tadahiro; Taruno, Hiroyuki; Watanabe, Katsunori; Tanimoto, Masahiro; Furui, Sora (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 .496 :346– 360.Bibcode :2018PPP...496..346I .doi :10.1016/j.palaeo.2018.02.002 .ISSN 0031-0182 . ^ Brochu, C.A.; Gingerich, P.D. (2000). "New tomistomine crocodylian from the Middle Eocene (Bartonian) of Wadi Hitan, Fayum Province, Egypt".University of Michigan Contributions from the Museum of Paleontology .30 (10):251– 268. ^ Harshman, J.; Huddleston, C. J.; Bollback, J. P.; Parsons, T. J.; Braun, M. J. (2003)."True and false gharials: A nuclear gene phylogeny of crocodylia" (PDF) .Systematic Biology .52 (3):386– 402.doi :10.1080/10635150309323 PMID 12775527 . Archived fromthe original (PDF) on 2022-10-09. Retrieved2021-06-30 . ^ Gatesy, Jorge; Amato, G.; Norell, M.; DeSalle, R.; Hayashi, C. (2003)."Combined support for wholesale taxic atavism in gavialine crocodylians" (PDF) .Systematic Biology .52 (3):403– 422.doi :10.1080/10635150309329 PMID 12775528 . ^ Willis, R. E.; McAliley, L. R.; Neeley, E. D.; Densmore Ld, L. D. (June 2007). "Evidence for placing the false gharial (Tomistoma schlegelii ) into the family Gavialidae: Inferences from nuclear gene sequences".Molecular Phylogenetics and Evolution .43 (3):787– 794.doi :10.1016/j.ympev.2007.02.005 .PMID 17433721 . ^ Gatesy, J.; Amato, G. (2008). "The rapid accumulation of consistent molecular support for intergeneric crocodylian relationships".Molecular Phylogenetics and Evolution 48 (3):1232– 1237.doi :10.1016/j.ympev.2008.02.009 .PMID 18372192 . ^ Erickson, G. M.; Gignac, P. M.; Steppan, S. J.; Lappin, A. K.; Vliet, K. A.; Brueggen, J. A.; Inouye, B. D.; Kledzik, D.; Webb, G. J. W. (2012). Claessens, Leon (ed.)."Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation" .PLOS ONE .7 (3) e31781.Bibcode :2012PLoSO...731781E .doi :10.1371/journal.pone.0031781 PMC 3303775 PMID 22431965 . ^a b Michael S. Y. Lee; Adam M. Yates (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 285 (1881).doi :10.1098/rspb.2018.1071 PMC 6030529 PMID 30051855 . ^ Hekkala, E.; Gatesy, J.; Narechania, A.; Meredith, R.; Russello, M.; Aardema, M. L.; Jensen, E.; Montanari, S.; Brochu, C.; Norell, M.; Amato, G. (2021-04-27)."Paleogenomics illuminates the evolutionary history of the extinct Holocene "horned" crocodile of Madagascar, Voay robustus" .Communications Biology .4 (1): 505.doi :10.1038/s42003-021-02017-0 ISSN 2399-3642 .PMC 8079395 PMID 33907305 .
Paratomistoma Paratomistoma courti
