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Pachycephalosaurus

Reptilia

Synonyms
Synonymy list
YearName and author
1872Tylosteus Leidy p. 40
1873Tylosteus Leidy p. 285
1890Tylosteus Zittel p. 610
1902Tylosteus Hay p. 477
1930Tylosteus Hay p. 239
1943Pachycephalosaurus Brown and Schlaikjer pp. 132-133
1945Pachycephalosaurus Sternberg p. 535
1956Pachycephalosaurus Romer p. 632
1964Pachycephalosaurus Estes p. 144
1964Pachycephalosaurus Kuhn p. 30
1964Tylosteus Kuhn p. 44
1964Pachycephalosaurus Tatarinov p. 589
1965Pachycephalosaurus Ostrom p. 39
1966Pachycephalosaurus Romer p. 370
1967Pachycephalosaurus Charig p. 716
1970Pachycephalosaurus Swinton p. 231
1974Pachycephalosaurus Galton p. 1064 fig. 6
1974Pachycephalosaurus Maryańska and Osmólska p. 47
1974Pachycephalosaurus Thulborn p. 173
1978Pachycephalosaurus Bonaparte p. 569
1978Pachycephalosaurus Dong p. 227
1979Pachycephalosaurus Wall and Galton p. 1183
1981Pachycephalosaurus McIntosh p. 35
1983Pachycephalosaurus Dodson p. 95
1983Stygimoloch Galton and Sues
1984Pachycephalosaurus Russell p. 27
1984Stygimoloch Russell p. 27
1985Pachycephalosaurus Breithaupt p. 169
1986Pachycephalosaurus Clemens p. 80
1986Stygimoloch Clemens p. 80
1986Pachycephalosaurus Sereno
1987Pachycephalosaurus Russell p. 10
1987Stygimoloch Sues and Galton
1987Pachycephalosaurus Sues and Galton p. 30
1988Pachycephalosaurus Carroll
1988Stygimoloch Carroll
1988Stenotholus Giffin et al.
1990Pachycephalosaurus Maryanska p. 566
1990Stygimoloch Maryanska p. 566
1994Pachycephalosaurus Olshevsky and Ford p. 91
1994Stygimoloch Olshevsky and Ford p. 91
1997Pachycephalosaurus Eberth p. 202
1997Pachycephalosaurus Sereno p. 440 fig. 2
1997Pachycephalosaurus Sues p. 512
1997Stygimoloch Sues p. 512
1998Stygimoloch Goodwin et al. p. 363
1998Pachycephalosaurus Goodwin et al. p. 371
1998Pachycephalosaurus Sereno p. 62
1999Pachycephalosaurus Sereno p. 2138 fig. 2
1999Stygimoloch Sereno p. 2138 fig. 2
2000Pachycephalosaurus Sereno pp. 500-501 fig. 25.8
2000Stygimoloch Sereno pp. 500-501 fig. 25.8
2001Pachycephalosaurus Eberth et al. p. 66
2003Pachycephalosaurus Sullivan p. 198
2003Stygimoloch Sullivan p. 199
2003Pachycephalosaurus Williamson and Carr fig. 11
2003Stygimoloch Williamson and Carr fig. 11
2004Pachycephalosaurus Maryanska et al. p. 465
2004Stygimoloch Maryanska et al. p. 466
2006Dracorex Bakker et al. pp. 331-332 figs. 1-12
2006Dracorex Sullivan p. 357
2006Pachycephalosaurus Sullivan p. 357
2006Stygimoloch Sullivan p. 359
2006Pachycephalosaurus Williamson and Carr p. 323
2006Stygimoloch Williamson and Carr p. 323
2008Pachycephalosaurus Butler et al. p. 8
2009Stygimoloch Schott et al. p. 781 fig. 8
2009Pachycephalosaurus Schott et al. p. 783 fig. 8
2009Pachycephalosaurus Williamson et al. p. 291
2016Pachycephalosaurus Goodwin and Evans p. 3
2020Pachycephalosaurus Dieudonné et al.
2021Dracorex Woodruff et al. p. 588 fig. 14
2021Pachycephalosaurus Woodruff et al. p. 588 fig. 14
2021Stygimoloch Woodruff et al. p. 588 fig. 14

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RankNameAuthor
kingdomAnimalia()
Bilateria
EubilateriaAx 1987
Life
Deuterostomia
phylumChordataHaeckel 1874
subphylumVertebrata
superclassGnathostomata
Osteichthyes()
subclassSarcopterygii()
subclassDipnotetrapodomorpha(Nelson 2006)
subclassTetrapodomorpha()
Tetrapoda
Reptiliomorpha
Anthracosauria
subclassAmphibiosauriaKuhn 1967
Cotylosauria()
Amniota
Sauropsida
classReptilia
RankNameAuthor
subclassEureptilia()
Romeriida
Diapsida()
Archosauromorpha(Huene 1946)
Crocopoda
ArchosauriformesGauthier 1986
Eucrocopoda
Archosauria()
informalAvemetatarsalia
Ornithodira
Dinosauromorpha
Dinosauriformes
Dinosauria()
Ornithischia()
Genasauria
Cerapoda
Marginocephalia
Pachycephalosauria()
Eupachycephalosauria
genusPachycephalosaurus

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.

G. †Pachycephalosaurus Brown and Schlaikjer 1943
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Invalid names: Dracorex hogwartsia Bakker et al. 2006 [synonym], Pachycephalosaurus grangeri Brown and Schlaikjer 1943 [synonym], Pachycephalosaurus reinheimeri Brown and Schlaikjer 1943 [synonym], Stygimoloch spinifer Galton and Sues 1983 [synonym], Tylosteus ornatus Leidy 1872 [synonym]
Invalid names: Dracorex Bakker et al. 2006 [synonym], Stygimoloch Galton and Sues 1983 [synonym], Tylosteus Leidy 1872 [synonym]
Diagnosis
No diagnoses are available
Measurements
No measurements are available
Composition: hydroxyapatiteo
Entire body: yesg
Adult length: 10 to < 100o
Adult width: 1.0 to < 10o
Adult height: 1.0 to < 10o
Maximum body mass: 1000 kgg
Minimum body mass: 30 kgg
Architecture: compact or denseo
Ontogeny: accretion, modification of partso
Grouping: gregariouso
Environment: terrestrialo
Locomotion: actively mobileo
Life habit: ground dwellingo
Diet: herbivoreo
Reproduction: oviparouso
Dispersal: direct/internalo
Dispersal 2: mobileo
Created: 2005-08-25 05:50:23
Modified: 2005-08-25 07:50:23
Source: g = genus, o = order
References: Peczkis 1995, Marsh 1875

Age range: base of the Maastrichtian to the top of the Lancian or 72.10000 to 66.00000 Ma

Collections (30 total)


Time interval Ma Country or state Original ID and collection number
Late/Upper Campanian83.5 - 70.6Canada (Alberta) P. sp. (59222)
Maastrichtian72.1 - 66.0USA (Montana) P. grangeri (47627) P. sp. (88987 88988) Predentata indet. (48848) Stenotholus kohleri (12977) Stygimoloch spinifer (47626 48844 48845 48846)
Maastrichtian72.1 - 66.0USA (North Dakota) Stygimoloch spinifer (48843)
Maastrichtian72.1 - 66.0USA (South Dakota) Dracorex hogwartsia (58813)
Lancian70.6 - 66.0USA (Montana) P. sp. (14616) Stygimoloch spinifer (14550)
Lancian70.6 - 66.0USA (Wyoming) P. sp. (72145) Stygimoloch spinifer (14544)
Late/Upper Maastrichtian70.6 - 66.0USA (Montana) P. sp. (183110) P. wyomingensis (52904 152397 161171) Tylosteus ornatus (91359)
Late/Upper Maastrichtian70.6 - 66.0USA (Wyoming) P. grangeri (14585) P. sp. (26760) P. wyomingensis (64644) Triceratops sp. (64645) Troodon wyomingensis (52106)
Late/Upper Maastrichtian70.6 - 66.0USA (South Dakota) P. sp., Dracorex hogwartsia (224484) P. wyomingensis, P. reinheimeri (47628)
Late/Upper Maastrichtian70.6 - 66.0USA (Colorado) P. sp. (49539)
Late/Upper Maastrichtian70.6 - 66.0Canada (Alberta) P. sp. (168404)