Tadzhikosuchus

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Tadzhikosuchus
Temporal range: TuronianSantonian
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Pseudosuchia
Superorder: Crocodylomorpha
Clade: Neosuchia
Genus: Tadzhikosuchus
Efimov, 1982
Type species
Tadzhikosuchus macrodentis
Efimov, 1982

Tadzhikosuchus is an extinct genus of neosuchian crocodyliform from the Late Cretaceous of Tajikistan. Three species have been named: the type species T. macrodentis, described by Efimov in 1982 from the lower Santonian-age Upper Cretaceous Ialovachsk Formation of Kansai, Tajikistan, in the Fergana Basin of Tajikistan; T. neutralis from the same location, by Efimov in 1988; and T. kizylkumensis from Turonian-age rocks of the Upper Cretaceous Bissekty Formation of Dzharakhuduk, Uzbekistan, by Nesov and colleagues in 1989. However, a 2000 review by Glenn Storrs and Mikhail Efimov could not differentiate between the species based on their type material, and recommended grouping the specimens of all three species under T. macrodentis. They also could not determine how Tadzhikosuchus and the contemporaneous Zhyrasuchus were related, or even if they were synonyms, due to the poor fossils available. [1] The name of the Tadzhikosuchus is derived from the Russian spelling of the name of the former Soviet republic of Tajikistan.

To date, Tadzhikosuchus is mostly known from partial dentaries, which were initially considered to have been very similar to Prodiplocynodon (a crocodyloid) by Efimov. However, since dentaries are not known for Prodiplocynodon, this conclusion was considered questionable by Jeremy Martin and Massimo Delfino in 2010. They instead suggested that it may have belonged to the Paralligatoridae, which was common in Asia at the time. [2]

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References

  1. Storrs, Glenn W.; Efimov, Mikhail B. (2000). "Mesozoic crocodyliforms of north-central Eurasia". In Benton, Michael J.; Shishkin, Mikhail A.; Unwin, David M.; Kurochkin, Evgenii N. (eds.). The Age of Dinosaurs in Russia and Mongolia. Cambridge: Cambridge University Press. pp. 402–419. ISBN   0-521-55476-4.
  2. Martin, J.E.; Delfino, M. (2010). "Recent advances in the comprehension of the biogeography of Cretaceous European eusuchians". Palaeogeography, Palaeoclimatology, Palaeoecology. 293 (3): 406–418. Bibcode:2010PPP...293..406M. doi:10.1016/j.palaeo.2009.10.021.