Khaan(/ˈkɑːn/;from Mongol[χaːŋ]'lord') is an extinct genus ofoviraptoriddinosaurknown from remains found in theDjadochta FormationofMongolia,dating to theLate Cretaceous(Campanian,75-71million years ago).[1]
| Khaan Temporal range:Late Cretaceous,
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| Holotype IGM 100/1127 | |
Scientific classification
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | Saurischia |
| Clade: | Theropoda |
| Family: | †Oviraptoridae |
| Subfamily: | †Heyuanninae |
| Genus: | †Khaan Clark, Norell &Barsbold,2001 |
| Species: | †K. mckennai
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| Binomial name | |
| †Khaan mckennai Clark, Norell, & Barsbold, 2001
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Description
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Khaandid not differ much from other oviraptorids. At first, its remains were assigned to "Ingenia",but theKhaanmanual structure, lacking the expansion of the upper thirdmetacarpal,was considered to differ sufficiently from that of "Ingenia" for it to be assigned to its own genus.
The oviraptorid diet is disputed, with plants and molluscs having been suggested. Like other oviraptorids,Khaanwas probably at least partially a meat eater, feeding on smallvertebrateslikemammals,lizardsand possibly other small dinosaurs. It was also probably feathered.
Discovery
editThetype speciesKhaan mckennaiwas named byJames M. Clarket al.in 2001. The genus name is derived fromMongolkhaan,"lord" or "ruler". Thespecific namehonours thepaleontologistMalcolm Carnegie McKenna.
TheholotypeIGM 100/1127 consists of an almost complete skeleton found together with another specimen, IGM 100/1002. Together they were informally referred to as "Romeo and Juliet". These individuals are about four feet long. A third, considerably larger, specimen, IGM 100/973, was referred to the species.
Classification
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Khaanwas by Clark assigned to theOviraptoridae.Among oviraptorids, it was probably more closely related toConchoraptor.
Thecladogrambelow follows an analysis by Fantiet al.,2012.[2]
| Oviraptoridae |
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Paleobiology
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According to a 2014 study published inNature,Khaanwas possiblysexually dimorphic.Two specimens, the holotype MPC-D 100/1127 and referred specimen MPC-D 100/1002, were analyzed, the dimorphic feature being in the anteriorchevrons.Both specimens were of the same size and build, and thus were likely the same age, ruling outontogeny.In MPC-D 100/1127, the anterior chevrons showed great similarity to those of other theropods, with no great expansion on the distal end. However, in the other individual, the chevrons had a "heel" -like expansion above the distal end, which increased in size along the sequence. The study ruled out a possibly pathologic explanation, finding sexual dimorphism to have more support. It was thought that the reduced spines were a female characteristic, because they would increase space for laying eggs. Also, the larger spines could be for male muscle attachments, which would support a tail fan.[3]
A 2022 study of the bite force ofKhaanand comparisons with other oviraptorosaurs such asIncisivosaurus,Citipati,andConchoraptorsuggests thatKhaanhad a very strong bite force. The moderate jaw gape seen in oviraptorosaurs is indicative of herbivory in the majority of the group, but it is clear they were likely feeding on much tougher or more types of vegetation than other herbivorous theropods in their environment, such as ornithomimosaurs and therizinosaurs were able to. The examinations suggest oviraptorosaurs may have been powerful-biting generalists or specialists that partook of niche partitioning both in body size and cranial function.[4]
See also
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References
edit- ^Clark, J. M.; Norell, M. A.; Barsbold, R. (2001). "Two new oviraptorids (Theropoda: Oviraptorosauria), Upper Cretaceous Djadokhta Formation, Ukhaa Tolgod, Mongolia".Journal of Vertebrate Paleontology.21(2): 209.doi:10.1671/0272-4634(2001)021[0209:TNOTOU]2.0.CO;2.S2CID86076568.
- ^Fanti, F; Currie, PJ; Badamgarav, D (2012)."New Specimens ofNemegtomaiafrom the Baruungoyot and Nemegt Formations (Late Cretaceous) of Mongolia ".PLOS ONE.7(2): e31330.Bibcode:2012PLoSO...731330F.doi:10.1371/journal.pone.0031330.PMC3275628.PMID22347465.
- ^Iv, W. S. P.; Funston, G. F.; Currie, P. J.; Norell, M. A. (2015)."A possible instance of sexual dimorphism in the tails of two oviraptorosaur dinosaurs".Scientific Reports.5:9472.Bibcode:2015NatSR...5E9472P.doi:10.1038/srep09472.PMC4379468.PMID25824625.
- ^Meade, Luke E.; Ma, Waisum (22 February 2022)."Cranial muscle reconstructions quantify adaptation for high bite forces in Oviraptorosauria".Scientific Reports.12(1): 3010.Bibcode:2022NatSR..12.3010M.doi:10.1038/s41598-022-06910-4.PMC8863891.PMID35194096.