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Stegoceras validum

Reptilia - Pachycephalosauridae

Synonyms
Synonymy list
YearName and author
1902Stegoceras validus Lambe p. 68
1905Stegoceras validus Lambe p. 24
1914Stegoceras validus Brown p. 378
1915Stegoceras validus Hennig p. 14
1918Stegoceras validus Lambe p. 25
1924Troodon validus Gilmore pp. 9-11
1924Troodon validus Parks p. 383
1927Troodon validus Huene p. 261
1930Troodon validus Hay
1930Troodon validus Russell p. 148
1931Troodon validus Gilmore pp. 4-5
1943Troodon validus Brown and Schlaikjer p. 128
1945Stegoceras validus Sternberg p. 536
1946Stegoceras validus Russell p. 171
1953Troodon validus Bohlin p. 32
1964Stegoceras validus Kuhn p. 31
1964Stegoceras validus Russell p. 12
1964Stegoceras validus Tatarinov p. 589
1966Stegoceras validus Russell p. 21
1974Stegoceras validus Maryanska and Osmolska p. 47
1979Stegoceras validus Wall and Galton p. 1177
1979Stegoceras browni Wall and Galton p. 1178
1980Stegoceras validus Wolberg p. 50
1983Ornatotholus browni Galton and Sues p. 469
1987Ornatotholus browni Sues and Galton
1987Stegoceras validum Sues and Galton p. 32
1989Stegoceras validum Giffin p. 528
1990Stegoceras validum Goodwin p. 191
1990Ornatotholus browni Maryanska p. 566
1990Stegoceras validum Maryanska p. 566
1997Stegoceras validus Eberth p. 201
1997Ornatotholus browni Sues p. 512
1997Stegoceras validum Sues p. 512
1997Stegoceras validum Vickaryous and Ryan p. 491
2001Stegoceras validum Eberth et al. p. 57
2001Stegoceras validum Horner et al. p. 10
2003Stegoceras validum Sullivan p. 185
2003Stegoceras validum Williamson and Carr fig. 11
2004Stegoceras validum Horner et al. p. 461
2004Ornatotholus browni Maryanska et al. p. 465
2004Stegoceras validum Maryanska et al. p. 465
2005Ornatotholus browni Currie p. 5
2005Stegoceras validum Currie p. 6
2005Stegoceras validum Ryan and Evans p. 319
2006Stegoceras validum Sullivan p. 357
2006Stegoceras validum Sullivan and Lucas p. 329
2008Stegoceras validum Longrich p. 994
2009Stegoceras validum Butler and Sullivan p. 29
2009Stegoceras validum Butler and Zhao p. 66
2009Stegoceras validum Schott et al. pp. 771-772
2009Stegoceras validum Williamson et al. p. 291
2010Stegoceras validum Lehman p. 788
2010Stegoceras validum Longrich et al. p. 280
2011Stegoceras validum Jasinski and Sullivan p. 203
2015Stegoceras validum Mallon et al. p. 429
2016Stegoceras validum Goodwin and Evans p. 6

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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
genusStegoceras
speciesvalidum()

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 1943A rather small species. Frontoparietal area relatively narrow and quadrangular in outline when viewed from above; low and gently arched in the immature stage, but strongly arched and deep in the adult. Prominent parieto-squamosal shelf behind the arched portion of the parietal. Frontals narrow where in contact with the nasals.
R. M. Sullivan 2003Differs from all other pachycephalosaurs in having a pronounced parietosquamosal shelf with an incipient frontoparietal dome; nasals inflated; postorbital situated posterolaterally on the dome; ornamentation consisting of numerous minute tubercles on lateral and posterior sides of squamosals with a prominent dorsal row of up to six tubercles on each squamosal and as many as two nodes on the medial posterior projection of the parietal.
S. E. Jasinski and R. M. Sullivan 2011Differs from Stegoceras novomexicanum in having a posterior extension of the parietal that is trapexoidal in shape; supratemporal fenestrae small, or absent, and, where open, located more laterally from the midline; squamosal sutural surface contacts splayed; robust and larger size.