Basic info Taxonomic history Classification Relationships
Morphology Ecology and taphonomy External Literature Search Age range and collections

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 pp. 1180-1181
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

Is something missing? Join the Paleobiology Database and enter the data

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.
Measurements
No measurements are available
Composition: hydroxyapatiteo
Entire body: yeso
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: 10 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: 2004-12-14 12:50:52
Modified: 2004-12-14 14:50:52
Source: g = genus, o = order
References: Kiessling 2004, Peczkis 1995, Marsh 1875

Age range: base of the Cenomanian to the top of the Lancian or 100.50000 to 66.00000 Ma

Collections (139 total)


Time interval Ma Country or state Original ID and collection number
Cenomanian - Turonian100.5 - 89.8Mongolia (Omnogov) Pachycephalosauria indet. (127666)
Late/Upper Santonian85.8 - 83.5Canada (Alberta) Acrotholus audeti (125521) Stegoceras sp. (68656)
Campanian83.6 - 72.1USA (New Mexico) Stegoceras novomexicanum (144518 144519)
Campanian83.6 - 72.1Canada (Alberta) Pachycephalosauridae indet. (45819 45821) Psalisauridae indet. (64647 64657 64662) Stegoceras brevis (64649 64650 64651) Stegoceras sp. (64661) Stegoceras validus (64646 64652 64658 64660) Troodon sternbergi (64648 64656) Troodon validus (64659 64663 64665)
Campanian83.6 - 72.1USA (Montana) Pachycephalosauridae indet. (22691 59373)
Campanian83.6 - 72.1Mongolia (Omnogov) Pachycephalosauridae indet. (181419)
Campanian - Maastrichtian83.6 - 66.0China (Nei Mongol) Troodon bexelli (50733)
Campanian - Maastrichtian83.6 - 66.0Mongolia (Omnogov) Pachycephalosauridae indet. (37019 180706)
Early/Lower Campanian83.5 - 70.6Canada (Alberta) Pachycephalosauridae indet. (181024)
Judithian83.5 - 70.6USA (Texas) Troodon sp. (14488 14489)
Late/Upper Campanian83.5 - 70.6USA (New Mexico) Pachycephalosauridae indet. (36541 53517) Prenocephale sp. (47821) Sphaerotholus goodwini (53514 53515) Stegoceras novomexicanum (144520) Stegoceras validum, Stegoceras novomexicanum (76714)
Late/Upper Campanian83.5 - 70.6USA (Alaska) Pachycephalosaurinae indet. (53494)
Late/Upper Campanian83.5 - 70.6Canada (Alberta) Ornatotholus browni (47629 48619) Pachycephalosauridae indet. (22697 45261 45262 45264 45671 45898 45899 47816 67871 67873 89605) Pachycephalosaurus sp. (59222) Stegoceras brevis, Stegoceras validus (60877) Stegoceras browni (48618) Stegoceras validus (60876) Stygimoloch sp. (76752) Troodon validus (53976 59107)
Late/Upper Campanian83.5 - 70.6USA (Texas) Pachycephalosauridae indet. (68001 68003 96599 96600 96601) Texacephale langstoni (22709)
Middle Campanian83.5 - 70.6Canada (Alberta) Gravitholus albertae (72144) Pachycephalosauridae indet. (45240 45560 45564 45566 45567 47794 47795 47809 67884) Stegoceras sp. (59378 59379) Troodon sp. (64654)
Middle Campanian - Late/Upper Campanian83.5 - 70.6Canada (Saskatchewan) Stegoceras sp. (14494)
Middle Campanian - Late/Upper Campanian83.5 - 70.6USA (Montana) Ornatotholus browni (50829) Pachycephalosauridae indet. (50830) Stegoceras sp. (14437 48620 50828 50906 50907) Stegoceras validum (14470 14491 50825 50826 50827 61452) Stegoceras validus (14446)
Late/Upper Campanian - Early/Lower Maastrichtian83.5 - 66.0USA (Texas) Texacephale langstoni (94373)
Late/Upper Campanian - Early/Lower Maastrichtian83.5 - 66.0Canada (Alberta) Pachycephalosauridae indet. (162136)
Late/Upper Campanian - Maastrichtian83.5 - 66.0Canada (Alberta) Troodon edmontonensis (64653)
Maastrichtian72.1 - 66.0USA (Montana) Pachycephalosauridae indet. (13142 85498 85499) Pachycephalosaurus grangeri (47627) Pachycephalosaurus sp. (88987 88988 183110) Pachycephalosaurus wyomingensis (52904) Predentata indet. (48848) Stegoceras edmontonense (53516) Stegoceras sp. (52903 72143) Stenotholus kohleri (12977) Stygimoloch spinifer (47626 48844 48845 48846) Tylosteus ornatus (91359)
Maastrichtian72.1 - 66.0USA (Wyoming) Pachycephalosauridae indet. (22638) Pachycephalosaurus wyomingensis (64644) Triceratops sp. (64645) Troodon wyomingensis (52106)
Maastrichtian72.1 - 66.0USA (South Dakota) Dracorex hogwartsia (58813) Pachycephalosaurus wyomingensis, Pachycephalosaurus reinheimeri (47628)
Maastrichtian72.1 - 66.0Canada (Saskatchewan) Sphaerotholus buccholtzae (170675)
Maastrichtian72.1 - 66.0Mongolia (Omnogov) Pachycephalosauridae indet. (127681)
Maastrichtian72.1 - 66.0USA (Colorado) Pachycephalosaurus sp. (49539)
Maastrichtian72.1 - 66.0USA (North Dakota) Stygimoloch spinifer (48843)
Lancian70.6 - 66.0Canada (Alberta) Pachycephalosaurus sp. (14569)
Lancian70.6 - 66.0USA (South Dakota) Pachycephalosauridae indet. (14537 192251)
Lancian70.6 - 66.0USA (North Dakota) Pachycephalosauridae indet. (137712 137715)
Lancian70.6 - 66.0USA (Wyoming) Pachycephalosaurus sp. (72145) Stygimoloch spinifer (14544)
Lancian70.6 - 66.0USA (Montana) Pachycephalosaurus sp. (14616) Stygimoloch spinifer (14550)
Late/Upper Maastrichtian70.6 - 66.0Canada (Alberta) Pachycephalosaurus sp. (168404)
Late/Upper Maastrichtian70.6 - 66.0Canada (Saskatchewan) Pachycephalosauridae indet. (54105)
Late/Upper Maastrichtian70.6 - 66.0USA (Montana) Pachycephalosaurus wyomingensis (152397 161171)
Late/Upper Maastrichtian70.6 - 66.0USA (Wyoming) Pachycephalosaurus grangeri (14585)