PBDB Taxon

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

Parksosaurus warreni

Reptilia - Thescelosauridae

Taxonomy

Thescelosaurus warreni was named by Parks (1926). Its type specimen is ROM 804, a partial skeleton, and it is a 3D body fossil. Its type locality is Rumsey Ferry road (100 ft level) [ROM], which is in a Maastrichtian terrestrial sandstone in the Horseshoe Canyon Formation of Canada. It is the type species of Parksosaurus.

It was recombined as Parksosaurus warrenae by Olshevsky (1992), Buchholz (2002); it was recombined as Parksosaurus warreni by Sternberg (1937), Sternberg (1940), Kuhn (1964), Russell (1964), Russell (1966), Russell and Chamney (1967), Lehman (1981), Weishampel and Weishampel (1983), Sues and Norman (1990), Weishampel and Heinrich (1992), Sues (1997), Eberth (1997), Eberth et al. (2001), Norman et al. (2004), Ryan and Evans (2005), Butler et al. (2008), Butler and Galton (2008), Boyd et al. (2009), Butler and Galton (2009), Butler and Sullivan (2009), Brown and Druckenmiller (2011), Han et al. (2012), Brown et al. (2013), Becerra et al. (2016), Herne et al. (2018), Bell et al. (2018), Madzia et al. (2018), Herne et al. (2019), Andrzejewski et al. (2019), Dieudonné et al. (2020), Sues et al. (2022).

Year	Name and author
1926	Thescelosaurus warreni Parks pp. 1-5
1927	Thescelosaurus warreni Huene p. 261
1930	Thescelosaurus warreni Hay p. 207
1930	Thescelosaurus warreni Russell p. 150
1933	Thescelosaurus warreni Russell p. 129
1935	Thescelosaurus warreni Parks p. 194
1936	Thescelosaurus warreni Swinton p. 574
1937	Parksosaurus warreni Sternberg p. 375
1940	Parksosaurus warreni Sternberg pp. 492-493
1964	Parksosaurus warreni Kuhn p. 8
1964	Parksosaurus warreni Russell p. 15
1966	Parksosaurus warreni Russell p. 29
1967	Parksosaurus warreni Russell and Chamney p. 12
1981	Parksosaurus warreni Lehman p. 203
1983	Parksosaurus warreni Weishampel and Weishampel p. 44
1990	Parksosaurus warreni Sues and Norman p. 500
1992	Parksosaurus warrenae Olshevsky p. 224
1992	Parksosaurus warreni Weishampel and Heinrich p. 171
1997	Parksosaurus warreni Eberth p. 201
1997	Parksosaurus warreni Sues p. 357
2001	Parksosaurus warreni Eberth et al. p. 66
2002	Parksosaurus warrenae Buchholz p. 19
2004	Parksosaurus warreni Norman et al. p. 395
2005	Parksosaurus warreni Ryan and Evans p. 329
2008	Parksosaurus warreni Butler and Galton p. 640
2008	Parksosaurus warreni Butler et al. p. 10
2009	Parksosaurus warreni Boyd et al. pp. 765-766
2009	Parksosaurus warreni Butler and Galton p. 640
2009	Parksosaurus warreni Butler and Sullivan p. 27
2011	Parksosaurus warreni Brown and Druckenmiller p. 1347
2012	Parksosaurus warreni Han et al. p. 1391 fig. 14
2013	Parksosaurus warreni Brown et al. p. 504
2016	Parksosaurus warreni Becerra et al. p. 568
2018	Parksosaurus warreni Bell et al. p. 12
2018	Parksosaurus warreni Herne et al. p. 15
2018	Parksosaurus warreni Madzia et al. p. 972
2019	Parksosaurus warreni Andrzejewski et al. p. 9
2019	Parksosaurus warreni Herne et al. p. 573
2020	Parksosaurus warreni Dieudonné et al.
2022	Parksosaurus warreni Sues et al.

Reference	Diagnosis
R. J. Butler et al. 2008	A dorsoventrally broad posterolateral process of the premaxilla and a postorbital process of the jugal that expands posterodorsally.
C. A. Boyd et al. 2009	This species was diagnosed by Galton (1995) as follows: deep posterior process of premaxilla; extensive suturai contact between maxilla and nasal; small, oval antorbital fenestra; squamosal transversely wide; well-enamelled surface of cheek teeth has numerous low, rounded ridges. Further preparation and study of ROM 804 is currently underway by other authors (D. Evans pers. comm.) that will provide more information about the anatomy of this species.
H.-D. Sues et al. 2022	Diagnosed by the following combination of character-states: Premaxilla with dorsoventrally deep posterolateral process. Antorbital fenestra small and teardrop-shaped. Broad contact between maxilla and prefrontal. Lateral surface of jugal devoid of sculpturing. Orbital margin of postorbital not rugose. Lingual surfaces of dentary teeth with 9 or 10 rounded, vertical ridges terminating in apical denticles; central ridge often more pronounced than others, with small, diagonally extending accessory grooves. Scapula without acromial ridge. Suprascapula mineralized or ossified. Dorsal margin of ischium posterodorsally concave at mid-length. Greater and lesser trochanters of the femur not separated by cleft. Chevrons on proximal and mid-caudal vertebrae with greatly expanded distal ends. More distal caudal vertebrae with greatly elongated prezygapophyses and lacking postzygapophyses.