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Pachycephalosaurus wyomingensis

Reptilia - Pachycephalosauridae

Synonyms
Synonymy list
YearName and author
1872Tylosteus ornatus Leidy p. 40
1931Troodon wyomingensis Gilmore pp. 1-6 figs. Pl. 1-5
1936Troodon wyomingensis Gilmore p. 10
1943Pachycephalosaurus grangeri Brown and Schlaikjer pp. 133-141 figs. Pl. 38-41
1943Pachycephalosaurus wyomingensis Brown and Schlaikjer pp. 142-143
1943Pachycephalosaurus reinheimeri Brown and Schlaikjer p. 143 figs. Pl. 42
1953Pachycephalosaurus grangeri Bohlin p. 32
1953Pachycephalosaurus reinheimeri Bohlin p. 32
1953Pachycephalosaurus wyomingensis Bohlin p. 32
1964Pachycephalosaurus grangeri Kuhn p. 30
1964Pachycephalosaurus reinheimeri Kuhn p. 30
1964Pachycephalosaurus wyomingensis Kuhn p. 30
1964Tylosteus ornatus Kuhn p. 44
1965Pachycephalosaurus wyomingensis Ostrom p. 39
1974Pachycephalosaurus grangeri Maryanska and Osmolska p. 47
1979Pachycephalosaurus wyomingensis Wall and Galton p. 1182
1981Pachycephalosaurus wyomingensis McIntosh p. 35
1983Stygimoloch spinifer Galton and Sues p. 463
1983Pachycephalosaurus wyomingensis Galton and Sues pp. 468-469
1985Pachycephalosaurus wyomingensis Breithaupt p. 169
1987Pachycephalosaurus wyomingensis Sues and Galton p. 30
1987Stygimoloch spinifer Sues and Galton p. 33
1988Stenotholus kohleri Giffin et al.
1989Pachycephalosaurus wyomingensis Giffin p. 525
1990Pachycephalosaurus wyomingensis Maryanska p. 566
1990Stygimoloch spinifer Maryanska p. 566
1991Stenotholus kohlerorum Olshevsky p. 22
1997Pachycephalosaurus wyomingensis Sues p. 512
1997Stygimoloch spinifer Sues p. 512
1997Stygimoloch spinifer Vickaryous and Ryan p. 491
1998Stygimoloch spinifer Goodwin et al. p. 363
2003Pachycephalosaurus wyomingensis Sullivan p. 198
2003Stygimoloch spinifer Sullivan p. 199
2003Pachycephalosaurus wyomingensis Williamson and Carr fig. 11
2003Stygimoloch spinifer Williamson and Carr fig. 11
2004Pachycephalosaurus wyomingensis Maryanska et al. p. 465
2004Stygimoloch spinifer Maryanska et al. p. 466
2006Dracorex hogwartsia Bakker et al. pp. 331-332 figs. 1-12
2006Dracorex hogwartsia Sullivan p. 357
2006Pachycephalosaurus wyomingensis Sullivan pp. 357-358
2006Stygimoloch spinifer Sullivan p. 359
2006Stygimoloch spinifer Williamson and Carr p. 325
2008Pachycephalosaurus wyomingensis Butler et al. p. 8
2009Pachycephalosaurus wyomingensis Schott et al. p. 783 fig. 8
2009Stygimoloch spinifer Schott et al. p. 783 fig. 8
2009Pachycephalosaurus wyomingensis Williamson et al. p. 293
2010Stygimoloch spinifer Lehman p. 790
2010Pachycephalosaurus wyomingensis Lehman p. 792
2010Dracorex hogwartsi Longrich et al. p. 280
2010Pachycephalosaurus wyomingensis Longrich et al. p. 280
2010Stygimoloch spinifer Longrich et al. p. 280
2012Pachycephalosaurus wyomingensis Han et al. p. 1370
2015Pachycephalosaurus wyomingensis Mallon et al. p. 426
2016Pachycephalosaurus wyomingensis Goodwin and Evans p. 3

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RankNameAuthor
kingdomAnimalia()
Triploblastica
Nephrozoa
Deuterostomia
phylumChordataHaeckel 1847
OlfactoresJefferies 1991
subphylumVertebrata
Gnathostomata()
Osteichthyes()
Sarcopterygii
subclassDipnotetrapodomorpha(Nelson 2006)
subclassTetrapodomorpha()
Tetrapoda()
Reptiliomorpha
Anthracosauria
Batrachosauria()
Cotylosauria()
Amniota
Sauropsida
classReptilia
subclassEureptilia()
Romeriida
Diapsida()
RankNameAuthor
Eosuchia()
Neodiapsida
SauriaGauthier 1984
Archosauromorpha(Huene 1946)
Crocopoda
ArchosauriformesGauthier 1986
Eucrocopoda
Archosauria()
informalAvemetatarsalia
Ornithodira
Dinosauromorpha
Dinosauriformes
Dinosauria()
Ornithischia()
Neornithischia()
Clypeodonta
Cerapoda
Marginocephalia
Pachycephalosauria()
familyPachycephalosauridae
Pachycephalosaurini
genusPachycephalosaurus
specieswyomingensis(Gilmore 1931)

If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.

Diagnosis
ReferenceDiagnosis
B. Brown and E. M. Schlaikjer 1943 (Pachycephalosaurus reinheimeri)Frontoparietal area very low, broad, and shallow. Prominent parietosquamosal shelf, with the posterior margin nodose and medially deeply notched. Frontals low and narrow where in contact with the nasals.
R. T. Bakker et al. 2006 (Dracorex hogwartsia)Most similar to Pachycephalosaurus and Stygimoloch, particularly in the long snout, two half-rings of pyramidal spikes on the snout, and strong cheek node. Differs from Pachycephalosaurus wyomingensis and Stygimoloch spinifer in lacking a dome; differs from S. spinifer in possessing four smaller spikes, not three massive spikes, on the squamosal, and lacking a dome. Differs from all other pachycephalosaurids in the extremely large supratemporal fenestrae, with the origin of the mandibular adductor muscles expanded anteriorly onto the dorsal surface of the parietal. Differs from the other monospecific genera (Homalocephale, Goyocephale, Wannanosaurus, and Stegoceras) with fenestrated skull tables, by having a long snout, two spike-half rings on the snout, parietal excluded from the posterior squamosal shelf, large cheek nodes, strong squamosal spike cluster on each side, generally strong accessory rugosities and longer snout.