Arstanosaurus

Arstanosaurus Temporal range: Late Cretaceous, 85–84  Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Hypothetical life reconstruction
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	† Ornithischia
Clade:	† Ornithopoda
Superfamily:	† Hadrosauroidea
Genus:	† Arstanosaurus Shilin & Suslov, 1982
Species:	†A. akkurganensis
Binomial name
†Arstanosaurus akkurganensis Shilin & Suslov, 1982

Arstanosaurus (meaning "Arstan lizard" after the Arstan well) is a genus of hadrosauroid dinosaur from the Santonian-Campanian-age Upper Cretaceous Bostobe Formation, Kazakhstan. It has had a confusing history, being considered both a hadrosaurid and a ceratopsid, or both at the same time (chimeric).

History

The genus was based on a partial left maxilla (holotype AAIZ 1/1 or IZ AN KSSR 1/1), with the lower end of a left femur (AAIZ 1/2) possibly referable. Both were found at Akkurgan-Boltyk near Qyzylorda and were named and described as Arstanosaurus akkurganensis in 1982. ^[1] This is not much material for naming a new genus, and it was largely ignored until the mid-1990s, when the hypothesis that it was really a ceratopsid appeared. ^[2] Shortly thereafter, a new revision appeared that showed that the characteristics listed as unusual for Arstanosaurus were really based on perspective, and that the maxilla was from an animal like Bactrosaurus , albeit indeterminate (a dubious name). The femur was uninformative. ^[3] It was regarded as an indeterminate hadrosaurid in the most recent review. ^[4]

Diagnostic hadrosauroid remains from the same area have in 2012 been named as Batyrosaurus . ^[5]

A hadrosauroid from the Bayan Shireh Formation (informally called "Gadolosaurus") has at times been identified as Arstanosaurus, but is clearly a distinct genus. ^{[6] [7] [8]}

Paleobiology

As a hadrosaurid, Arstanosaurus would have been a bipedal/quadrupedal herbivore, eating plants with sets of ever-replacing teeth stacked on each other. ^[4]

See also

• Dinosaurs portal

• Timeline of hadrosaur research

References

1. Shilin, F.V., and Suslov, Y.V. (1982). A hadrosaur from the northeastern Aral Region. Paleontological Journal1982(1):132-136 [translated version].
2. Nesov, L.A. (1995). Dinozavri severnoi Yevrasii: Novye dannye o sostave kompleksov, ekologii i paleobiogeografii [Dinosaurs of Northern Eurasia: new data about assemblages, ecology and paleobiogeography]. Scientific Research Institute of the Earth's Crust. St. Petersburg State University:St. Petersburg, Russia, 156 pp. + 14 pl. [Russian].
3. Norman, D.B., and Kurzanov, S.M. (1982). On Asian ornithopods (Dinosauria: Ornithischia). 2. Arstanaosaurus akkurganensis Shilin and Suslov, 1982. Proceedings of Geologists' Association108(3):191-199.
4. Horner, J.R., Weishampel, D.B., and Forster, C.A. (2004). Hadrosauridae. In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). The Dinosauria (second edition). University of California Press:Berkeley, 438-463. ISBN   0-520-06727-4.
5. Pascal Godefroit, François Escuillié, Yuri L. Bolotsky & Pascaline Lauters, 2012, "A New Basal Hadrosauroid Dinosaur from the Upper Cretaceous of Kazakhstan". In: Godefroit, P. (eds). Bernissart Dinosaurs and Early Cretaceous Terrestrial Ecosystems. Indiana University Press. pp. 335–362
6. Lambert, David; the Diagram Group (1990). The Dinosaur Data Book. New York: Avon Books. p. 63. ISBN   0-380-75896-2.
7. Norman, David B.; Sues, Hans-Dieter (2000). "Ornithopods from Kazakhstan, Mongolia and Siberia". In Benton, Michael J.; Shishkin, Mikhail A.; Unwin, David M.; Kurochkin, Evgenii N. The Age of Dinosaurs in Russia and Mongolia. Cambridge: Cambridge University Press. pp. 462–479. ISBN   0-521-55476-4.
8. Tsogtbaatar, K., D. Weishampel, D. C. Evans, and M. Watabe. (In review). A New Hadrosauroid (Dinosauria: Ornithopoda) from the Late Cretaceous Baynshire Formation of the Gobi Desert (Mongolia). PLOS ONE