Caenagnathasia

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Caenagnathasia
Temporal range: Turonian-Maastrichtian, 93–70.6 Ma
Illustration of the lower jaw
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: Caenagnathidae
Subfamily: Elmisaurinae
Genus: Caenagnathasia
Currie et al., 1994
Species:
C. martinsoni
Binomial name
Caenagnathasia martinsoni
Currie et al., 1994

Caenagnathasia ('recent jaw from Asia') is a small caenagnathid oviraptorosaurian theropod from the Late Cretaceous of Uzbekistan.

Discovery[edit]

The type species Caenagnathasia martinsoni was named and described in 1994 by Philip J. Currie, Stephen Godfrey and Lev Nesov. The generic name is a combination of a reference to the species' placement in the Caenagnathidae, with Asia, the continent of its provenance. The specific name honours Gerbert Genrikhovich Martinson. The genus is based on holotype N 401/12457, a pair of fused dentaries of the lower jaws. The specimen was found near Dzharakuduk in layers of the Bissekty Formation, dating to the Turonian-Coniacian, around 90 mya, making it the oldest known caenagnathoid. A second specimen was referred to the species, N 402/12457, a right dentary of a slightly smaller individual. Both individuals were adult.[1] In 2015, new material of Caenagnathasia was described. From the same site as the holotype, the material includes various vertebrae, a dentary, and a femur.[2]

Description[edit]

Caenagnathasia is the smallest known oviraptorosaur and one of the smallest non-avian dinosaurs. The jaw fragments are only a few centimetres long and total skull length has been estimated at 3 inches (7.6 cm). A 2010 estimate by Gregory S. Paul gave it a length of 2 feet (0.61 m) and a weight of 3 pounds (1.4 kg).[3] Caenagnathasia would presumably have resembled other oviraptorosaurs, which were feathered, bird-like dinosaurs with beaked skulls, long necks, and long limbs. Recent studies suggest it was one of the more primitive members of the Caenagnathidae.

Classification[edit]

Caenagnathasia was originally assigned to the Caenagnathidae. It was even included in the definition of that clade published by Hans-Dieter Sues.[4] It has been suggested however, that it might have a more basal position in the Oviraptorosauria, outside of the Caenagnathoidea.[5] In 2015 after the description of new material, it was found that Caenagnathasia could confidently be referred to Caenagnathidae.[2]

Life restoration with purely hypothetical ecology

The below cladogram is based on that resolved in the description of Anzu.[6]

Caenagnathoidea
Caenagnathidae

Microvenator celer

Gigantoraptor erlianensis

Caenagnathasia martinsoni

Alberta dentary morph 3

Leptorhynchos gaddisi

"Caenagnathus" sternbergi

Oviraptoridae

See also[edit]

References[edit]

  1. ^ Currie, P.J.; Godfrey, S.J.; Nessov, L. (1994). "New caenagnathid (Dinosauria, Theropoda) specimens from the Upper Cretaceous of North America and Asia". Canadian Journal of Earth Sciences. 30 (10–11): 2255–2272. doi:10.1139/e93-196.
  2. ^ a b Sues, H.-D.; Averianov, A. (2015). "New material of Caenagnathasia martinsoni (Dinosauria: Theropoda: Oviraptorosauria) from the Bissekty Formation (Upper Cretaceous: Turonian) of Uzbekistan". Cretaceous Research. 54: 50–59. doi:10.1016/j.cretres.2014.12.001.
  3. ^ Paul, G.S., 2010, The Princeton Field Guide to Dinosaurs, Princeton University Press p. 152
  4. ^ Sues, Hans-Dieter (1997). "On Chirostenotes, a Late Cretaceous oviraptorosaur (Dinosauria: Theropoda) from western North America". Journal of Vertebrate Paleontology. 17 (4): 698–716.
  5. ^ Holtz, Thomas R. Jr. (2010) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages, Winter 2010 Appendix.
  6. ^ Lamanna, M. C.; Sues, H. D.; Schachner, E. R.; Lyson, T. R. (2014). "A New Large-Bodied Oviraptorosaurian Theropod Dinosaur from the Latest Cretaceous of Western North America". PLOS ONE. 9 (3): e92022. Bibcode:2014PLoSO...992022L. doi:10.1371/journal.pone.0092022. PMC 3960162. PMID 24647078.

External links[edit]