Pseudhesperosuchus

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Pseudhesperosuchus
Temporal range: Norian
Pseudhesperosuchus.jpg
Restored skeleton
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Crocodylomorpha
Genus: Pseudhesperosuchus
Bonaparte 1969
Species

Pseudhesperosuchus (meaning "false Hesperosuchus ") is a genus of sphenosuchian, a type of basal crocodylomorph, the clade that comprises the crocodilians and their closest kin. It is known from a partial skeleton and skull found in rocks of the Late Triassic (Norian-age) Los Colorados Formation of the Ischigualasto-Villa Unión Basin in northwestern Argentina.

History and description

Pseudhesperosuchus is based on PVL  3830. This specimen consists of a skull and lower jaws, most of the vertebral column, the shoulder girdle, and parts of the arms and legs. The genus was named by José Bonaparte in 1969. The type species is P. jachaleri. [1] The skull, though nearly complete, is poorly preserved, and some of its bones and sutures have been misidentified over the years. [2] A 2002 phylogenetic analysis of sphenosuchians performed by James Clark and Hans–Dieter Sues found Pseudhesperosuchus to have an unresolved position along with several other sphenosuchians, neither closer to true crocodiles or to Sphenosuchus . [3] The genus is sometimes misspelled Pseudohesperosuchus, as in Carroll (1988). [4]

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References

  1. Bonaparte, José F. (1969). "Dos nuevos "faunas" de reptiles triásicos de Argentina". Gondwana Stratigraphy. Paris: UNESCO. pp. 283–306.
  2. Clark, James M., James M.; Sues, Hans–Dieter; Berman, Davd S. (2000). "A new specimen of Hesperosuchus agilis from the Upper Triassic of New Mexico and the interrelationships of basal crocodylomorph archosaurs". Journal of Vertebrate Paleontology. 20 (4): 683–704. doi:10.1671/0272-4634(2000)020[0683:ANSOHA]2.0.CO;2.
  3. Clark, James M.; Sues, Hans-Dieter (2002). "Two new species of basal crocodylomorphs and the status of the Sphenosuchia". Zoological Journal of the Linnean Society. 136 (1): 77–96. doi: 10.1046/j.1096-3642.2002.00026.x .
  4. Carroll, Robert L. (1988). Vertebrate Paleontology and Evolution . W.H. Freeman & Co. ISBN   0-7167-1822-7.