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Troodontidae

Taxonomy

Troodontidae was named by Gilmore (1924). It was considered monophyletic by Zheng et al. (2009).

It was synonymized subjectively with Pachycephalosauridae by Romer (1956), Romer (1966) and Maryanska and Osmolska (1974).

It was assigned to Ornithopoda by Russell (1930) and Brown and Schlaikjer (1943); to Orthopoda by Gilmore (1924) and Bohlin (1953); to Protoavia by Paul (1988); to Oviraptorosauria by Russell and Dong (1994); to Bullatosauria by Holtz (1994), Nessov (1995) and Holtz and Padian (1995); to Coelurosauria by Currie (1995) and Zinke (1998); to Theropoda by Eberth et al. (2001); to Theropoda by Russell (1948) and Peng et al. (2001); to Saurischia by Pearson et al. (2002) and Sankey et al. (2002); to Arctometatarsalia by Holtz (1995), Holtz (1998) and Senter et al. (2004); to Theropoda by Chure et al. (2006); to Deinonychosauria by Gauthier (1986), Sereno (1997), Sereno (1998), Sereno (1999), Rauhut (2003) and Zheng et al. (2009); to Paraves by Holtz (2000) and Zanno et al. (2011); to Maniraptora by Benton (1990), Osmolska (1990), Chatterjee (1993), Makovicky and Norell (2004), Xu et al. (2011) and Xu et al. (2012); and to Eumaniraptora by Godefroit et al. (2013).

Subtaxa

Archaeornithoides, Borogovia, Byronosaurus, Geminiraptor, Jinfengopteryx, Linhevenator, Mei, Philovenator, Saurornithoides, Sinornithoides, Sinovenator, Sinusonasus, Talos, Tochisaurus, Troodon (syn. Polyodontosaurus, Stenonychosaurus, Pectinodon), Urbacodon, Xixiasaurus, Zanabazar

Sister taxa

Dromaeosauridae

Download authority and opinion data - View classification of included taxa

Synonyms

Saurornithoididae was named by Barsbold (1974). It is not extant.

It was synonymized subjectively with Troodontidae by Gauthier (1986), Osmolska (1990), Nessov (1995) and Makovicky and Norell (2004).

It was assigned to Deinonychosauria by Barsbold (1976), Barsbold (1977), Russell (1984), Gauthier and Padian (1985) and Buffetaut et al. (1986); to Theropoda by Barsbold (1974), Rozhdestvensky (1977) and Carroll (1988); and to Coelurosauria by Barsbold (1983) and Dong (1992).
Bradycneme was named by Harrison and Walker (1975). It is not extant. It is the type genus of Bradycnemidae.

It was considered a nomen dubium by Makovicky and Norell (2004).

It was assigned to Bradycnemidae by Harrison and Walker (1975); to Theropoda by Buffetaut et al. (1986); to Theropoda by Carroll (1988); and to Troodontidae by Paul (1988) and Weishampel et al. (1991).
Heptasteornis was named by Harrison and Walker (1975).

It was synonymized subjectively with Troodon by Paul (1988); it was considered a nomen dubium by Makovicky and Norell (2004) and Martinelli and Vera (2007).

It was assigned to Bradycnemidae by Harrison and Walker (1975); to Theropoda by Buffetaut et al. (1986); to Theropoda by Carroll (1988); and to Troodontidae by Weishampel et al. (1991).
Laelaps laevifrons was named by Cope (1876). Its type specimen is AMNH 3961, a tooth, and it is not a trace fossil.

It was recombined as Dryptosaurus laevifrons by Hay (1902) and Steel (1970); it was recombined as Dromaeosaurus laevifrons by Matthew and Brown (1922) and Russell (1930); it was considered a nomen dubium by Makovicky and Norell (2004).
Euronychodon was named by Antunes and Sigogneau-Russell (1991).

It was considered a nomen dubium by Makovicky and Norell (2004).

It was assigned to Dromaeosauridae by Antunes and Sigogneau-Russell (1991); to Coeluridae by Antunes and Sigogneau (1992); to Troodontidae by Galton (1996); to Theropoda by Nessov (1995) and Currie (2000); and to Coelurosauria by Barco and Ruiz-Omeñaca (2001).
Euronychodon portucalensis was named by Antunes and Sigogneau-Russell (1991). Its type specimen is CEGUNL-TV 20, a tooth, and it is not a trace fossil. Its type locality is "Cerâmica do Mondego" quarry, Taveiro, which is in a Maastrichtian fluvial claystone in the Argilas de Aveiro Formation of Portugal.

It was considered a nomen dubium by Le Loeuff (1998) and Makovicky and Norell (2004).
Laelaps cristatus was named by Cope (1876). Its type specimen is AMNH 3954, a tooth, and it is not a trace fossil.

It was recombined as Dryptosaurus cristatus by Hay (1902) and Steel (1970); it was recombined as Dromaeosaurus cristatus by Matthew and Brown (1922); it was recombined as Troodon cristatus by Olshevsky (2000); it was considered a nomen dubium by Makovicky and Norell (2004).
Bradycneme draculae was named by Harrison and Walker (1975). It is not extant. Its type specimen is BMNH A.1588. Its type locality is Szentpéterfalva, Hateg Basin, which is in a Maastrichtian terrestrial horizon in the Sânpetru Formation of Romania.

It was considered a nomen dubium by Makovicky and Norell (2004).
Heptasteornis andrewsi was named by Harrison and Walker (1975). Its type specimen is BMNH A.4359, a limb element (distal end, left tibiotarsus), and it is a 3D body fossil. Its type locality is Szentpéterfalva, Hateg Basin, which is in a Maastrichtian terrestrial horizon in the Sânpetru Formation of Romania.

It was recombined as Troodon andrewsi by Paul (1988); it was considered a nomen dubium by Makovicky and Norell (2004).
Koparion was named by Chure (1994). It is not extant.

It was considered a nomen dubium by Makovicky and Norell (2004).

It was assigned to Troodontidae by Chure (1994) and Chure et al. (2006).
Koparion douglassi was named by Chure (1994). It is not extant. Its type specimen is DINO 3353. Its type locality is Rainbow Park (DNM 94), which is in a Kimmeridgian/Tithonian wet floodplain horizon in the Morrison Formation of Utah.

It was considered a nomen dubium by Makovicky and Norell (2004).
Euronychodon asiaticus was named by Nessov (1995). Its type specimen is CCMGE 9/12454, a set of teeth, and it is not a trace fossil. Its type locality is CBI-14, Dzharakuduk, which is in a Coniacian terrestrial horizon in the Bissekty Formation of Uzbekistan.

It was considered a nomen dubium by Makovicky and Norell (2004).

Synonymy list

Year	Name and author
1876	Laelaps cristatus Cope p. 344
1876	Laelaps laevifrons Cope p. 344
1877	Laelaps cristatus Cope p. 572
1877	Laelaps laevifrons Cope p. 572
1902	Dryptosaurus cristatus Hay p. 488
1902	Dryptosaurus laevifrons Hay p. 488
1922	Dromaeosaurus cristatus Matthew and Brown p. 376
1922	Dromaeosaurus laevifrons Matthew and Brown p. 376
1924	Troodontidae Gilmore pp. 7-8
1930	Dromaeosaurus laevifrons Russell p. 142
1930	Troodontidae Russell p. 142
1943	Troodontidae Brown and Schlaikjer p. 126
1948	Troodontidae Russell p. 629
1953	Troodontidae Bohlin p. 32
1970	Dryptosaurus cristatus Steel p. 31
1970	Dryptosaurus laevifrons Steel p. 31
1974	Saurornithoididae Barsbold p. 7
1975	Heptasteornis andrewsi Harrison and Walker pp. 399-400 figs. Pl. 65:6-7; Pl. 66:1-7
1975	Bradycneme Harrison and Walker pp. 564-565
1975	Bradycneme draculae Harrison and Walker p. 565 figs. Pl. 65:1-5
1975	Heptasteornis Harrison and Walker p. 566 figs. Pl. 65:6-7; Pl. 66:1-7
1975	Heptasteornis andrewsi Harrison and Walker p. 566 figs. Pl. 65:6-7; Pl. 66:1-7
1976	Saurornithoididae Barsbold p. 74
1977	Saurornithoididae Barsbold p. 50
1977	Saurornithoididae Rozhdestvensky p. 112
1983	Saurornithoididae Barsbold p. 86
1984	Saurornithoididae Russell p. 28
1985	Saurornithoididae Gauthier and Padian p. 190
1986	Bradycneme Buffetaut et al. p. 1395
1986	Bradycneme draculae Buffetaut et al. p. 1395
1986	Heptasteornis Buffetaut et al. p. 1395
1986	Heptasteornis andrewsi Buffetaut et al. p. 1395
1986	Saurornithoididae Buffetaut et al. p. 1395
1986	Troodontidae Gauthier p. 11
1988	Bradycneme Carroll
1988	Heptasteornis Carroll
1988	Saurornithoididae Carroll
1988	Troodontidae Paul p. 394
1988	Troodon andrewsi Paul pp. 399-400
1988	Bradycneme Paul p. 400
1988	Bradycneme draculae Paul p. 400
1990	Troodontidae Benton p. 19
1990	Troodontidae Osmolska p. 150
1991	Euronychodon portucalensis Antunes and Sigogneau-Russell pp. 114, 117
1991	Euronychodon Antunes and Sigogneau-Russell p. 117
1991	Euronychodon portucalensis Antunes and Sigogneau-Russell p. 117
1991	Bradycneme Weishampel et al. p. 209
1991	Bradycneme draculae Weishampel et al. p. 209
1991	Heptasteornis Weishampel et al. p. 209
1991	Heptasteornis andrewsi Weishampel et al. p. 209
1992	Euronychodon Antunes and Sigogneau pp. 54-55
1992	Euronychodon portucalensis Antunes and Sigogneau pp. 54-55
1992	Saurornithoididae Dong p. 164
1993	Troodontidae Chatterjee p. 283
1994	Koparion Chure p. 11
1994	Koparion douglassi Chure p. 11 figs. Pl. 1
1994	Troodontidae Holtz, Jr.
1994	Troodontidae Russell and Dong p. 2125
1995	Troodontidae Currie p. 25A
1995	Troodontidae Holtz, Jr. p. 35A
1995	Troodontidae Holtz, Jr. and Padian p. 35A
1995	Troodontidae Nessov p. 41
1995	Euronychodon Nessov p. 44
1995	Euronychodon asiaticus Nessov p. 44
1995	Euronychodon portucalensis Nessov p. 44
1996	Euronychodon Galton p. 89
1996	Euronychodon portucalensis Galton p. 89
1997	Troodontidae Sereno p. 444
1998	Troodontidae Holtz, Jr. p. 40
1998	Troodontidae Sereno p. 65
1998	Troodontidae Zinke p. 184
1999	Troodontidae Sereno p. 2139 fig. 2
2000	Koparion douglassi Chure p. 2
2000	Euronychodon Currie p. 450
2000	Euronychodon asiaticus Currie p. 450
2000	Troodontidae Holtz, Jr. p. 13 fig. 5
2000	Troodon cristatus Olshevsky p. 97
2001	Euronychodon Barco and Ruiz-Omeñaca p. 243
2001	Troodontidae Eberth et al. p. 56
2001	Troodontidae Peng et al. p. 37
2002	Troodontidae Pearson et al. p. 154
2002	Troodontidae Sankey et al. p. 755
2003	Bradycneme draculae Grigorescu p. 100
2003	Heptasteornis andrewsi Grigorescu p. 100
2003	Troodontidae Rauhut p. 159
2004	Troodontidae Makovicky and Norell p. 185
2004	Troodontidae Senter et al. p. 2 fig. 2
2005	Koparion douglassi Carpenter et al. pp. 24-26
2006	Koparion Chure et al. p. 236
2006	Koparion douglassi Chure et al. p. 236
2006	Troodontidae Chure et al. p. 236
2006	Bradycneme draculae Dalla Vecchia p. 13
2006	Heptasteornis andrewsi Dalla Vecchia p. 13
2006	Euronychodon portucalensis Mateus et al. p. 123
2009	Troodontidae Zheng et al.
2011	Troodontidae Xu et al. p. 2
2011	Troodontidae Zanno et al. p. 3
2012	Troodontidae Xu et al. p. 141
2013	Troodontidae Godefroit et al.

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