Alaskacephale
Alaskacephale was a genus of pachycephalosaurid dinosaur from the Prince Creek Formation, that lived in the early Maastrichtian stages of the Late Cretaceous (around 71 to 69 million years ago).
| Alaskacephale Temporal range: Early Maastrichtian, | |
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Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Order: | †Ornithischia |
| Suborder: | †Pachycephalosauria |
| Family: | †Pachycephalosauridae |
| Genus: | †Alaskacephale Sullivan, 2006 |
| Species: | †A. gangloffi |
| Binomial name | |
| †Alaskacephale gangloffi Sullivan, 2006 | |
Discovery
Alaskacephale was named by Robert Sullivan in 2006.[1] The genus name refers to Alaska, where the holotype was discovered, combined with the Greek kephale, meaning head. The species name, gangloffi, honors paleontologist Roland Gangloff. The only known specimen of A. gangloffi is the holotype UAM AK-493-V-001, found in 1999, a nearly complete left squamosal with a characteristic array of polygonal nodes. The dimensions of this bone suggest that A. gangloffi was about half the size of Pachycephalosaurus wyomingensis or three quarters the size of Prenocephale, and about the same size as Sphaerotholus edmontonensis and Foraminacephale.[2]
The specimen was previously described by Gangloff et al. (2005) as an unnamed pachycephalosaurid, possibly a Pachycephalosaurus. Gangloff et al. described the squamosal as having an interdigitated suture with the quadrate, a feature previously described only in Pachycephalosaurus. Sullivan (2006) opined that this "suture" is instead a breakage point in both Alaskacephale and Pachycephalosaurus, so it could not be used to unite the two taxa.
Classification
Within the tribe Pachycephalosaurini, Alaskacephale is very closely related to Pachycephalosaurus wyomingensis. Below is a cladogram from Evans et al., 2021.[3]
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References
- Sullivan, RM (2006). "A taxonomic review of the Pachycephalosauridae (Dinosauria: Ornithischia)". New Mexico Museum of Natural History and Science Bulletin (35): 347–365.
- Gangloff, R.A.; A.R. Fiorillo; D.W. Norton (2005). "The first pachycephalosaurine (Dinosauria) from the Paleo-Arctic of Alaska and its paleogeographic implications". Journal of Paleontology. 79 (5): 997–1001. doi:10.1666/0022-3360(2005)079[0997:tfpdft]2.0.co;2. S2CID 130669713.
- Evans, David; Brown, Caleb M.; You, Hailu; Campione, Nicolás E. (2021). "Description and revised diagnosis of Asia's first recorded pachycephalosaurid, Sinocephale bexelli gen. nov., from the Upper Cretaceous of Inner Mongolia, China". Canadian Journal of Earth Sciences. 58 (10): 981–992. Bibcode:2021CaJES..58..981E. doi:10.1139/cjes-2020-0190. S2CID 244227050.
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