Microsuchus

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Microsuchus
Temporal range: Santonian
~85.8–84.9  Ma
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Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Clade: Notosuchia
Genus: Microsuchus
De Saez, 1928
Type species
Microsuchus schilleri
De Saez, 1928

Microsuchus is an extinct genus of mesoeucrocodylians, belonging to Notosuchia. [1] Fossils have been found in the Bajo de la Carpa Formation, dating to the Santonian stage of the Late Cretaceous. [2]

Contents

Classification

Originally classified as a goniopholidid on the basis of the platycoelous vertebral centra, [3] Microsuchus was recently redescribed and recovered as either a neosuchian or notosuchian. Diagnostic features include the presence of a bulge lateral to the prezygapophyses of the second sacral vertebra, elongated posterior zeugopodia, and proximal caudal centra with a triangular cross section. [4] A 2017 cladistic analysis of Razanandrongobe further clarified the phylogenetic position of Microsuchus by recovering it as a primitive notosuchian. [5]

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References

  1. Mook, C. C. (1934). "The evolution and classification of the crocodilia". The Journal of Geology. 42 (3): 295–304. Bibcode:1934JG.....42..295M. doi:10.1086/624165. S2CID   128568052.
  2. Markwick, P. J. (1998). "Crocodilian diversity in space and time: The role of climate in paleoecology and its implication for understanding K/T extinctions". Paleobiology. 24 (4): 470–497. Bibcode:1998Pbio...24..470M. doi:10.1017/S009483730002011X. JSTOR   2401182.
  3. Saez, M. D. d. (1928). "Un nuevo goniofolido Argentino". Anales de la Sociedad Cientifica Argentina, Buenos Aires. 105: 287–290.
  4. Leardi, Juan Martín; Fiorelli, Lucas E.; Gasparini, Zulma (2015). "Redescription and reevaluation of the taxonomical status of Microsuchus schilleri (Crocodyliformes: Mesoeucrocodylia) from the Upper Cretaceous of Neuquén, Argentina". Cretaceous Research. 52: 153–166. Bibcode:2015CrRes..52..153L. doi:10.1016/j.cretres.2014.09.007. hdl: 11336/124599 .
  5. Dal Sasso C, Pasini G, Fleury G, Maganuco S. (2017) Razanandrongobe sakalavae, a gigantic mesoeucrocodylian from the Middle Jurassic of Madagascar, is the oldest known notosuchian. PeerJ 5:e3481 https://doi.org/10.7717/peerj.3481