Khurendukhosaurus
| Khurendukhosaurus Temporal range: Early Cretaceous | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Sauropsida |
| Subclass: | Diapsida |
| Infraclass: | Archosauromorpha? |
| Order: | Choristodera |
| Genus: | Khurendukhosaurus Sigogneau–Russell & Efimov, 1984 |
| Species | |
| |
Khurendukhosaurus is a genus of choristodere, a type of amphibious reptile. It is known from Lower Cretaceous rocks of Mongolia and Russia. Two species have been named. The type species, K. orlovi, was named in 1984 by Sigogneau–Russell and Efimov for the fragmentary postcranial skeleton PIN 3386/3. This specimen was discovered in the Aptian-age Lower Cretaceous Hühteeg Svita Formation at Hüren Dukh, central Mongolia. The lake deposits at this site also contain fossils of the choristoderes Irenosaurus and Tchoiria.[1] Other postcranial bones of K. orlovi have been found at this site as well.[1][2]
Second species K. bajkalensis was named by Efimov in 1996 for PIN 2234/201, consisting of a scapulocoracoid and a rib.[1] These bones were found in the Lower Cretaceous Murtoi Formation at Lake Gusinoye, Buryatia, Russia.[3] The first Russian choristodere, Efimov and Storrs (2000) found it difficult to distinguish from K. orlovi based on the small amount of material.[1] Skutschas (2008) reported on additional material which supported the placement of the Russian taxon within Khurendukhosaurus, but found the species K. bajkalensis to be dubious within the genus.[3]
Khurendukhosaurus was a small choristodere, approximately 1 metre (3.3 ft) long at most. Efimov and Storrs regarded it as a basal member of Choristodera,[1] but Skutschas was unable to confirm this in a phylogenetic analysis.[3] It may have been related to the hyphalosaurids, a group of long–necked choristoderes.[2] The neural spines of the tail are elongate, suggesting that it swam by using a tall tail.[2]
References
- 1 2 3 4 5 Efimov, Mikhail B.; Storrs, Glenn W. (2000). "Choristodera from the Lower Cretaceous of northern Asia". 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. 390–401. ISBN 0-521-55476-4.
- 1 2 3 Matsumoto, Ryoko; Suzuki, Shigeru; Tsogtbaatar, Khisigjav; Evans, Susan E. (2009). "New material of the enigmatic reptile Khurendukhosaurus (Diapsida: Choristodera) from Mongolia". Naturwissenschaften. 96 (2): 233–242. doi:10.1007/s00114-008-0469-6. PMID 19034405.
- 1 2 3 Skutschas, Pavel P. (2008). "A choristoderan reptile from the Lower Cretaceous of Transbaikalia, Russia". Neues Jahrbuch für Geologie und Paläontologie Abhandlungen. 247 (1): 63–78. doi:10.1127/0077-7749/2008/0247-0063.