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Pachycephalosauridae

Reptilia - Pachycephalosauridae

Synonyms
Synonymy list
YearName and author
1945Pachycephalosauridae Sternberg pp. 535-536
1953Troodon bexelli Bohlin p. 32
1956Pachycephalosauridae Romer p. 631
1963Pachycephalosauridae Parsch p. 4
1964Pachycephalosauridae Estes p. 144
1964Pachycephalosauridae Kuhn p. 30
1964Stegoceras bexelli Kuhn p. 32
1964Pachycephalosauridae Tatarinov p. 588
1966Pachycephalosauridae Romer p. 370
1970Pachycephalosauridae Swinton p. 200
1971Pachycephalosauridae Galton p. 40
1974Pachycephalosauridae Galton p. 1064 fig. 6
1974Pachycephalosauridae Maryanska and Osmolska p. 50
1974Pachycephalosauridae Thulborn p. 173
1977Pachycephalosauridae Rozhdestvensky p. 114
1977Pachycephalosauridae Thulborn p. 726 fig. 1
1978Pachycephalosauridae Bonaparte p. 331
1978Pachycephalosauridae Dong p. 225
1979Pachycephalosauridae Benton p. 143
1979Pachycephalosauridae Sues and Taquet
1979Gravitholus Wall and Galton p. 1180
1979Pachycephalosauridae Wall and Galton p. 1185
1980Pachycephalosauridae Bonaparte p. 82
1980Troodon bexell Chao
1980Gravitholus Currie pp. 29-30
1980Pachycephalosauridae Ostrom p. 22
1981Pachycephalosauridae McIntosh p. 35
1983Gravitholus Dodson p. 95
1983Pachycephalosauridae Zhao p. 301
1984Pachycephalosauridae Norman pp. 160-162 fig. 2
1984Gravitholus Russell p. 25
1984Pachycephalosauridae Russell p. 29
1985Pachycephalosauridae Cooper p. 291
1986Pachycephalosauridae Bakker p. 461
1986Gravitholus Clemens p. 80
1986Tholocephalidae Sereno
1986Stegoceras bexell Zhao p. 71
1987Gravitholus Sues and Galton
1987Pachycephalosauridae Sues and Galton
1988Gravitholus Carroll
1988Pachycephalosauridae Carroll
1990Gravitholus Maryanska p. 566
1990Pachycephalosauridae Maryanska p. 566
1992Pachycephalosauridae Dong p. 166
1997Troodon bexelli Mateer p. 662
1997Pachycephalosauridae Sereno p. 443
1997Pachycephalosauridae Sues p. 512
1998Pachycephalosauridae Goodwin et al. p. 363
1998Pachycephalosauridae Sereno p. 62
1999Pachycephalosauridae Sereno p. 2138 fig. 2
2000Pachycephalosauridae Sereno p. 482
2001Pachycephalosauridae Eberth et al. p. 57
2001Pachycephalosauridae Peng et al. p. 36
2003Pachycephalosauridae Williamson and Carr fig. 11
2004Gravitholus Maryanska et al. p. 465
2004Pachycephalosauridae Maryanska et al. p. 465
2006Pachycephalosauridae Sullivan p. 349
2008Pachycephalosauridae Butler et al. pp. 22-23 figs. 2-4
2010Texacephale Longrich et al.
2010Texacephale langstoni Longrich et al. p. 276 figs. 3-5
2011Pachycephalosauridae Jasinski and Sullivan p. 202
2011Pachycephalosauridae Watabe et al. p. 490
2012Pachycephalosauridae Han et al. p. 1391 fig. 14
2013Pachycephalosauridae Evans et al. p. 2
2013Texacephale langstoni Longrich et al. p. 24

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RankNameAuthor
kingdomAnimalia()
Triploblastica
Nephrozoa
Deuterostomia
phylumChordataHaeckel 1847
subphylumVertebrata
superclassGnathostomata
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
familyPachycephalosauridae

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
T. Maryanska and H. Osmolska 1974Bipedal, highly specialized ornithischians, small to moderate in size. Pubis does not take part in formation of acetabulum. Skull roof thickened, flat to dome-like. Supratemporal fenestra usually closed in highly domed forms. Antorbital fenestra occasionally present. Maxilla penetrated by extensive intramaxillary sinus. Epipterygoid present and being in contact with the prootic. Orbits anteriorly and medially closed by accessory sphenethmoidal ossifications. Quadrate with tendency to oblique po sition ofits dorsal portion. Jugal excluded from posterior boundary ofinfratemporal fenestra and together with quadratojugal strongly expanded ventrally to level ofarticular surface ofquadrate. Basicranial region strongly shortened (sag.), nearly completely separated from palatal and suborbital regions by extension of quadrate and pterygoid and by juncture of basisphenoid and prootic with quadrate wing of the pterygoid. Basal tubera thin, plate-like. Occipital and basicranial regions usually placed almost in the same vertical plane. Premaxillary dentition present, heterodonty more or less pronounced. Dentition weak, teeth arranged in one row, enameled on both sides. External skull bones strongly ornamented. Dorsal vertebrae mostly with tongue and groove articulation of zygapophyses. Caudal ribs strongly developed on anterior caudals. Tibia shorter or equal in length to femur. Pes tetradactyl.
R. M. Sullivan 2006Ornithischian dinosaurs with thickened, fully-flat or incipiently to fully-domed frontoparietals, broad and flattened postorbital-squamosal bar; supratemporal fenestrae absent to well-developed; broad exposure of the occiput; quadrate and ventral surface of squamosal (occipital plate) directed anteroventrally; squamosals developed into deep plates on the occiput with greatly enlarged upper-outer corners; two supraorbital elements lateral to the frontal; arched premaxillary-maxillary diastema; broad postorbital-jugal bar, plate-shaped basal tubera, variably developed nodes on the squamosal (either in rows or clusters), nasals and other parts of the skull.