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

Troodon formosus

Reptilia - Troodontidae

Taxonomy
Troodon formosus was named by Leidy (1856). Its type specimen is ANSP 9259, a tooth, and it is a 3D body fossil. Its type locality is Judith River badlands (USGS), which is in a Campanian/Campanian terrestrial horizon in the Judith River Formation of Montana. It was considered monophyletic by Currie (2000).

It was synonymized subjectively with Saurornithoides inequalis by Carpenter (1982); it was considered a nomen vanum by Sues (1977).

Synonymy list
YearName and author
1856Troodon formosus Leidy p. 72
1857Troodon formosus Leidy p. 90
1860Troodon formosus Leidy p. 147
1870Troodon formosus Cope p. 120
1874Troodon formosus Cope p. 26
1875Troodon formosus Cope p. 248
1877Troodon formosus Cope p. 572
1902Troodon formosus Hay p. 490
1902Troodon formosus Lambe p. 47
1905Troodon formosus Lambe p. 25
1908Troodon formosus Brown p. 192
1914Troodon formosus Brown p. 378
1915Troodon formosus Hennig p. 14
1924Troodon formosus Gilmore p. 8
1927Troodon formosus Huene p. 261
1930Troodon formosus Hay p. 208
1930Troodon formosus Russell p. 142
1931Troodon formosus Gilmore p. 5
1943Troodon formosus Brown and Schlaikjer p. 127
1945Troodon formosus Sternberg p. 534
1946Troodon formosus Russell p. 171
1948Troodon formosus Russell p. 629
1951Troodon formosus Sternberg p. 257
1964Troodon formosus Russell p. 10
1970Troodon formosus Steel p. 17
1970Troodon formosus Swinton p. 229
1980Troodon formosus Wolberg p. 50
1986Troodon formosus Gauthier p. 11
1987Troodon formosus Currie
1988Troodon formosus Paul p. 397
1990Troodon formosus Currie et al. p. 113
1991Troodon formosus Kurzanov and Osmólska p. 70
1992Troodon formosus Currie p. 238
1994Troodon formosus Chure p. 14
1994Troodon formosus Currie and Peng p. 2226
1994Troodon formosus Currie and Zhao p. 2233
1994Troodon formosus Derstler p. 142
1994Troodon formosus Rauhut and Kriwet p. 181
1994Troodon formosus Russell and Dong p. 2166
1997Troodon formosus Eberth p. 201
1997Troodon formosus Erickson p. 5
1997Troodon formosus Hernández-Rivera p. 434
1997Troodon formosus Norell and Makovicky p. 20
1997Troodon formosus Ryan and Vickaryous p. 170
1997Troodon formosus Varricchio p. 749
1998Troodon formosus Makovicky and Norell p. 3
1999Troodon formosus Breithaupt p. 60
2000Troodon formosus Currie p. 276
2000Troodon formosus Norell et al. p. 9
2000Troodon formosus Zelenitsky et al. p. 130
2001Troodon formosus Currie and Dong p. 1753
2001Troodon formosus Eberth et al. p. 58
2001Troodon formosus Horner et al. p. 8
2001Troodon formosus Larsson p. 23
2001Troodon formosus Peng et al. p. 37
2002Troodon formosus Sankey et al. p. 755
2002Troodon formosus Varricchio
2002Troodon formosus Varricchio et al. p. 564
2003Troodon formosus Makovicky et al. p. 25 fig. 21
2003Troodon formosus Rauhut p. 42
2004Troodon formosus Makovicky and Norell p. 185
2004Troodon formosus Senter et al. p. 5
2005Troodon formosus Buffetaut et al. p. 480
2006Troodon formosus Johnson et al. p. 579
2007Troodon formosus Averianov and Sues p. 94
2007Troodon formosus Turner et al. p. 3
2008Troodon formosus Cooper et al.
2008Troodon formosus Fiorillo p. 323
2009Troodon formosus Bever and Norell p. 3
2009Troodon formosus Fiorillo et al. p. 181
2009Troodon formosus Godefroit et al.
2009Troodon formosus Norell et al. p. 5
2009Troodon formosus van der Lubbe et al. p. 406
2010Troodon formosus Jackson et al. p. 255
2010Troodon formosus Lü et al. p. 381
2010Troodon formosus Paulina Carabajal and Canale p. 249
2010Troodon formosus Zanno et al. p. 180
2011Troodon formosus Brown and Druckenmiller p. 1343
2011Troodon formosus Genise and Sarzetti p. 820
2011Troodon formosus Goianechini and Apesteguía p. 166
2011Troodon formosus Martin and Varricchio p. 15
2011Troodon formosus Porfiri et al. p. 112
2011Troodon formosus Turner et al. p. 7
2011Troodon formosus Zanno et al. p. 2
2012Troodon formosus Gao et al. p. 5
2012Troodon formosus Prieto-Marquez et al. p. 122
2012Troodon formosus Xu et al. p. 144
2013Troodon formosus Araújo et al. p. 7
2013Troodon formosus Larson and Currie p. 9
2013Troodon formosus Zanno et al. p. 518
2014Troodon formosus Hendrickx and Mateus p. 19
2014Troodon formosus Moreno-Azanza et al. p. 850
2014Troodon formosus Rivera-Sylva and Carpenter p. 148
2014Troodon formosus Williamson and Brusatte p. 17
2015Troodon formosus Currie and Koppelhus p. 626
2015Troodon formosus Peecook and Sidor p. 9
2015Troodon formosus Varricchio et al. p. 3
2016Troodon formosus Lee p. 1
2016Troodon formosus Mallon et al. p. 33
2018Troodon formosus Norell et al. p. 38
2021Troodon formosus Sellés et al. p. 8

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

RankNameAuthor
kingdomAnimalia()
—Bilateria
—EubilateriaAx 1987
—Deuterostomia
phylumChordataHaeckel 1874
subphylumVertebrata
superclassGnathostomata
—Osteichthyes()
subclassSarcopterygii()
subclassDipnotetrapodomorpha(Nelson 2006)
subclassTetrapodomorpha()
—Tetrapoda
—Reptiliomorpha
—Anthracosauria
subclassAmphibiosauriaKuhn 1967
—Cotylosauria()
—Amniota
—Sauropsida
classReptilia
subclassEureptilia()
—Romeriida
—Diapsida()
RankNameAuthor
—Archosauromorpha(Huene 1946)
—Crocopoda
—ArchosauriformesGauthier 1986
—Eucrocopoda
—Archosauria()
informalAvemetatarsalia
—Ornithodira
—Dinosauromorpha
—Dinosauriformes
—Dinosauria()
—Theropoda()
—Neotheropoda
—AverostraPaul 2002
—Tetanurae
—Coelurosauria()
—Maniraptora
—Paraves
infraorderDeinonychosauria
familyTroodontidae
subfamilyTroodontinae
genusTroodon
speciesformosus

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.

†Troodon formosus Leidy 1856
show all | hide all
Diagnosis
ReferenceDiagnosis
B. Brown and E. M. Schlaikjer 1943Premaxillary tooth with smoothly curved conves central area of the outer side. Marginal denticulations strong and clearly defined.
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
Architecture: compact or denseo
Ontogeny: accretion, modification of partso
Grouping: solitaryo
Environment: terrestrialf
Locomotion: actively mobileo
Life habit: ground dwellingf
Diet: carnivoref
Diet 2: omnivoref
Reproduction: oviparousf
Dispersal: direct/internalo
Dispersal 2: mobileo
Created: 2005-08-24 13:19:43
Modified: 2005-08-24 15:19:43
Source: g = genus, f = family, o = order
References: Marsh 1875, Peczkis 1995, Holtz et al. 2000

Age range: base of the Late/Upper Campanian to the top of the Lancian or 83.50000 to 66.00000 Ma

Collections (54 total)


Time interval Ma Country or state Original ID and collection number
Campanian83.6 - 72.1Canada (Alberta) Troodon formosus (58808)
Late/Upper Campanian83.5 - 70.6Canada (Alberta) Stenonychosaurus inequalis (184041) Troodon formosus (22659 22695 22697 22698 34307 34309 45264 45671 45892 45893 45897 45898 47784 47807 47811 47812 53050 64325 64326 76030) Troodontidae indet. (52991)
Late/Upper Campanian83.5 - 70.6USA (Montana) Troodon formosus (22689 59373) Troodon sp. (25658)
Middle Campanian83.5 - 70.6USA (Montana) Hypsilophodontidae indet. (13281) Troodon formosus (14437) Troodon formosus, Theropoda indet. (14453)
Middle Campanian83.5 - 70.6Canada (Alberta) Saurornithoididae indet. (61470) Troodon formosus (45240 47795 47809)
Middle Campanian - Late/Upper Campanian83.5 - 70.6USA (Montana) Troodon formosus (14446 14457 14490 50907 59217 64643 type locality: 69213) Troodon sp. (14462)
Middle Campanian - Late/Upper Campanian83.5 - 70.6Canada (Alberta) Troodon formosus (45821)
Early/Lower Maastrichtian70.6 - 66.0Canada (Alberta) Troodon formosus (64324)
Early/Lower Maastrichtian70.6 - 66.0USA (Alaska) Troodon formosus (51889 51892 51893 88975) Troodon sp. (51890)
Lancian70.6 - 66.0USA (Wyoming) Troodon formosus (14542 14543 75298 75435 75442)
Late/Upper Maastrichtian70.6 - 66.0Russian Federation (Chukot) Troodon sp. (59386)