"Crocodylus" megarhinus

Species of reptile (fossil) "Crocodylus" megarhinus Early Oligocene, 33.9 28.1 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 10.7717/peerj.12094 34567843 8428266 free "Crocodylus" megarhinus "Crocodylus" megarhinus Andrews, 1905 Crocodylus articeps Andrews, 1906 "Crocodylus" megarhinus is an extinct species of crocodile from the Eocene of Egypt. A partial skull was found by British paleontologist Charles William Andrews in the Fayum Depression. Andrews named Crocodylus megarhinus in 1905 on the basis of the holotype skull. A complete skull was also uncovered from Egypt in 1907 but was not recognized as "C." megarhinus until 1927.Mook C.C. 1927 The skull characters of Crocodilus megarhinus Andrews American Museum Novitates 289 1–8 http://digitallibrary.amnh.org/dspace/bitstream/2246/3158/1/N0289.pdf "C." megarhinus shares many features with living crocodiles like the Nile crocodile (C. niloticus), including a robust triangular skull that is shorter than most other crocodiles. Similarities are also seen in the teeth of the two species. Like living crocodiles, "C." megarhinus has several constricted areas along the upper jaw that provide spaces for the teeth of the lower jaw when the mouth is closed. The proportions of "C." megarhinus and C. niloticus are so similar that American paleontologist Charles C. Mook considered it "very probable that C. megarhinus is a direct ancestor of C. niloticus." A second Fayum crocodilian, "Crocodylus" articeps, was named alongside "C." megarhinus. Andrews distinguished "C." articeps from "C." megarhinus on the basis of its narrower snout, which is more similar to the slender-snouted crocodile than the Nile crocodile. "C." articeps has recently been synonymized with "C." megarhinus, and may represent a less mature form in the species' population.Brochu C. A. 2000 Phylogenetic relationships and divergence timing of Crocodylus based on morphology and the fossil record Copeia 2000 3 657–673 10.1643/0045-8511(2000)000[0657:pradto]2.0.co;2 Although it has traditionally been described as a species of Crocodylus, "C." megarhinus has been placed outside the genus in many recent phylogenetic analyses. A new genus has not yet been erected for the species. "C." megarhinus is usually found to be a basal crocodyline outside the genus but still more closely related to it than the false gharial or mekosuchines. Below is a cladogram modified from Puértolas et al. (2011) showing its phylogenetic placement among crocodiles:Eduardo Puértolas José I. Canudo Penélope Cruzado-Caballero 2011 A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids PLOS ONE 6 6 e20011 10.1371/journal.pone.0020011 21687705 3110596 2011PLoSO...620011P free font-size:85%;line-height:85% Crocodyloidea Prodiplocynodon Asiatosuchus Arenysuchus "Crocodylus" affinis Brachyuranochampsa "Crocodylus" acer Crocodylidae Tomistominae Mekosuchinae "Crocodylus" megarhinus Crocodylus Voay Osteolaemus A 2017 paper by Wu et al. (2017) recovers "Crocodylus" megarhinus as a relative of mekosuchines.Xiao-Chun Wu Chun Li Yan-Yin Wang 2017 Taxonomic reassessment and phylogenetic test of Asiatosuchus nanlingensis Young, 1964 and Eoalligator chunyii Young, 1964 Vertebrata PalAsiatica 56 2 137–146 https://www.researchgate.net/publication/324584171 A 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data established the inter-relationships within Crocodylia,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 10.1098/rspb.2018.1071 30051855 6030529 free which was expanded upon in 2021 by Hekkala et al. using paleogenomics by extracting DNA from the extinct Voay.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 en 4 1 505 10.1038/s42003-021-02017-0 33907305 8079395 2399-3642 free The below cladogram shows the results of the latest study, and how "C." megarhinus may be outside of Crocodylidae, as a basal member of Crocodyloidea (and perhaps the sole additional taxon beyond Crocodylidae): font-size:85%;line-height:85% Crocodylia (crown group) Alligatoroidea (stem group) extinct basal Alligatoroids Alligatoridae (crown group) Caimaninae Caiman 90 px Melanosuchus 120 px Paleosuchus 90 px Alligatorinae Alligator 100 px Longirostres (crown group) Crocodyloidea (stem group) "Crocodylus" megarhinus Crocodylidae (crown group) Crocodylus 90 px Mecistops 90 px Osteolaemus 90 px Gavialoidea (stem group) extinct basal Gavialoids Gavialidae (crown group) Gavialis 110 px Tomistoma 90 px References C. Q5187413 Category:Crocodyloidea Category:Eocene crocodylomorphs Category:Paleogene reptiles of Africa Category:Fossil taxa described in 1905 Category:Articles with quotation marks in the title Category:Taxa named by Charles William Andrews