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Triceratops utahensis

Reptilia - Ceratopsidae

Taxonomy
Arrhinoceratops utahensis was named by Gilmore (1946). Its type specimen is USNM 15583. Its type locality is west side, North Horn Mountain, which is in a Maastrichtian terrestrial horizon in the North Horn Formation of Utah.

It was synonymized subjectively with Arrhinoceratops brachyops by Kuhn (1964); it was recombined as Torosaurus utahensis by Lawson (1976), Tyson (1981), Tokaryk (1986), Lehman (1987), Wu et al. (2007), Hunt and Lehman (2008), Farke (2011) and Longrich and Field (2012); it was synonymized subjectively with Torosaurus latus by Dodson and Currie (1990), Lehman (1990), Hunt and Lucas (1992) and Dodson et al. (2004); it was recombined as Triceratops utahensis by Longrich (2014).

Synonymy list
YearName and author
1946Arrhinoceratops utahensis Gilmore pp. 42-47 fig. 12
1976Torosaurus utahensis Lawson p. 162
1981Torosaurus utahensis Tyson p. 1247
1986Torosaurus utahensis Tokaryk p. 195
1987Torosaurus utahensis Lehman p. 206
2007Torosaurus utahensis Wu et al. p. 1260
2008Torosaurus utahensis Hunt and Lehman pp. 1128-1129
2011Torosaurus utahensis Farke p. 6
2012Torosaurus utahensis Longrich and Field p. 5
2014Triceratops utahensis Longrich p. 303 fig. 8

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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()
Eosuchia()
Neodiapsida
RankNameAuthor
SauriaGauthier 1984
Archosauromorpha(Huene 1946)
Crocopoda
ArchosauriformesGauthier 1986
Eucrocopoda
Archosauria()
informalAvemetatarsalia
Ornithodira
Dinosauromorpha
Dinosauriformes
Dinosauria()
Ornithischia()
Neornithischia()
Clypeodonta
Cerapoda
Marginocephalia
Ceratopsia()
infraorderNeoceratopsia
Coronosauria
familyCeratopsidae
subfamilyChasmosaurinae
Triceratopsini
genusTriceratops
speciesutahensis()

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
R. K. Hunt and T. M. Lehman 2008Torosaurus utahensis differs from T. latus in having a squamosal without a thickened medial bar along the parietal suture and having a parietal with an epiparietal on the midline (modified from Farke, 2007).
Body mass estimates
estimateequationreference
 7.23 tons Ceratopsidae femur circumferenceAnderson et al. 1985
 2.19 tons Ceratopsidae humerus circumferenceAnderson et al. 1985
mean: 3.98 tons
Measurements
partNmean
femur circumference1376.0
humerus circumference1274.0

Composition: hydroxyapatiteo
Entire body: yesg
Adult length: 10 to < 100o
Adult width: 1.0 to < 10o
Adult height: 1.0 to < 10o
Architecture: compact or denseo
Ontogeny: accretion, modification of partso
Grouping: gregariouso
Environment: terrestrialsubo
Locomotion: actively mobileo
Life habit: ground dwellingsubo
Diet: herbivoresubo
Reproduction: oviparouso
Dispersal: direct/internalo
Dispersal 2: mobileo
Created: 2005-08-25 05:45:07
Modified: 2005-08-25 07:45:07
Source: g = genus, subo = suborder, o = order
References: Kiessling 2004, Peczkis 1995, Norman and Weishampel 1991, Marsh 1875

Age range: Maastrichtian or 72.10000 to 66.00000 Ma

Collections (3 total)


Time interval Ma Country or state Original ID and collection number
Maastrichtian72.1 - 66.0USA (Utah) Ceratopsia indet. (type locality: 45719)
Maastrichtian72.1 - 66.0USA (Texas) Torosaurus utahensis (69211 85188)