Biology:Urbacodon

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Short description: Extinct genus of dinosaurs


Urbacodon
Temporal range: Late Cretaceous, 95 Ma
Scientific classification edit
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Troodontidae
Subfamily: Troodontinae
Genus: Urbacodon
Averianov & Sues, 2007
Species:
U. itemirensis
Binomial name
Urbacodon itemirensis
Averianov & Sues, 2007

Urbacodon (meaning "URBAC tooth") is a genus of troodontid dinosaur, a type of small carnivore. It lived in Uzbekistan during the early Late Cretaceous Period, about 95 million years ago.

Discovery and naming

On 9 September 2004, a lower jaw of a small theropod was uncovered by Anton Sergeevich Rezwiy near Itemir in the IT-01 quarry.[1]

The type species, Urbacodon itemirensis, was named by Alexandr Averianov and Hans-Dieter Sues in 2007. The first part of the generic name Urbacodon is an acronym, honouring the Uzbek, Russian, British, American and Canadian scientists who participated in its discovery. This acronym was combined with a Greek ὀδών, odon, "tooth". The specific name refers to the provenance from Itemir.[1]

The name was based on the holotype ZIN PH 944/16, a single left dentary with preserved replacement teeth from the Cenomanian Dzharakuduk Formation. Averianov and Sues also identified teeth and other material, earlier described by Lev Nesov, as a Urbacodon sp. from the nearby Turonian Bissekty Formation.[1]

Description

The holotype dentary of U. itemirensis is 79.2 millimetres long (3.12 in) and has 32 tooth positions. It is rather straight in top view. The teeth are closely packed but between the front twenty-four teeth and the rear eight teeth, a distinctive gap is present, a diastema. This is a unique trait but was not formally designated as an autapomorphy because it might be the result of individual variation. Urbacodon resembles Byronosaurus and Mei but differs from most other Troodontidae in that its teeth lack serrations. Urbacodon is distinguished from Byronosaurus by a less vascularized lateral dentary groove and more bulbous anterior tooth crowns, and from Mei by considerably larger size.[1]

Classification

Averianov and Sues viewed Urbacodon as more plesiomorphic than Troodon and Saurornithoides in having a straight dentary with fewer teeth, but did not attempt to place it on a cladogram.[1] In 2010, a cladistic analysis showed it as a close relative of Byronosaurus and Xixiasaurus.[2]

See also

References

  1. 1.0 1.1 1.2 1.3 1.4 Averianov, A.O.; Sues, H.-D. (2007). "A new troodontid (Dinosauria: Theropoda) from the Cenomanian of Uzbekistan, with a review of troodontid records from the territories of the former Soviet Union". Journal of Vertebrate Paleontology 27 (1): 87–98. doi:10.1671/0272-4634(2007)27[87:ANTDTF2.0.CO;2]. 
  2. Lü J.-C, Xu L., Liu Y.-Q., Zhang X.-L., Jia S. & Ji Q., 2010, "A new troodontid (Theropoda: Troodontidae) from the Late Cretaceous of central China, and the radiation of Asian troodontids", Acta Palaeontologica Polonica 55(3): 381-388

Wikidata ☰ Q1950821 entry