Characters and Character-States

1.Premaxilla, width at oral margin:

Weishampel et al. 1993: char. 1 modified; Head 1998: char. 1 modified; Norman 1998: char. 1 modified; Norman 2002: char. 1 and 2 modified; Kobayashi & Azuma 2003: char. 1 modified; You et al. 2003: char. 7 modified; Godefroit et al. 2004a: char. 11 modified; Godefroit et al. 2004b: char. 9 modified; Horner et al. 2004: char. 20 modified; Suzuki et al. 2004: char. 1 modified; Prieto-Marquez et al. 2006a: char. 14 modified; Prieto-Marquez etal. 2006b: char. 63 modified; Gates & Sampson 2007: char. 22 modified; Godefroit et al. 2008: char. 9.

0.narrow, expanded laterally less than two times width at narrowest point (postoral constriction), margin oriented nearly vertically

1.expanded transversely to more than two times postoral constriction, margin flared laterally into more horizontal orientation

2.Premaxilla, reflected rim:

Weishampel et al. 1993: char. 3; Norman 1998: char. 4 modified; Norman 2002: char. 3 modified; Godefroit et al. 2004a: char. 12 modified; Horner et al., 2004: char. 21 modified; Prieto-Marquez, 2005: char. 15 modified; Prieto-Marquez et al. 2006a: char. 15 modified; Prieto-Marquez et al. 2006b: char. 64 modified; Gates & Sampson 2007: char. 23 modified; Godefroit et al. 2008: char. 10 modified.

0.absent

1.deflected at anterolateral corner and posteriorly reflected

2.reflected along entire rim

3.Premaxilla, anterior bill margin shape:

Horner et al. 2004: char. 22; Prieto-Marquez et al. 2006a: char. 16; Evans & Reisz 2007: char. 2; Gates & Sampson 2007: char. 24.

0.horseshoe-shaped, forming continuous semicircle that curves smoothly to postoral constriction

1.broadly arcuate across anterior margin, constricts abruptly behind oral margin

4.Premaxillary foramen ventral to anterior margin of external nares that opens onto the palate and connected by a canal to the narial fossa:

Weishampel et al. 1993: char. 4 modified; Head1998: char. 2; Godefroit et al. 2004b: char. 7 modified; Horner et al. 2004: char. 23; Suzuki et al. 2004: char. 2 modified; Prieto-Marquez2005: char. 16; Prieto-Marquez et al. 2006a: char. 17; Prieto-Marquez et al. 2006b: char. 67; Gates Sampson 2007: char. 25.

0.absent

1.present

5.Premaxilla, accessory foramen entering premaxilla in outer narial fossa, located anterior to premaxillary foramen:

Horner et al. 2004: char. 24; Prieto-Marquez et al. 2006a: char. 18; Prieto-Marquez et al. 2006b: char. 69; Gates & Sampson 2007: char. 26.

0.absent

1.present, empties into common chamber with premaxillary foramen, then onto palate

6.Premaxilla, oral margin with a "double layer" structure consisting of an external denticle-bearing layer seen externally and an internal palatal layer of thickened bone set back slightly from the oral margin and separated from the denticulate layer:

You et al. 2003: char. 11; Horner et al. 2004: char. 25; Prieto-Marquez et al. 2006a: char. 19; Prieto-Marquez et al. 2006b: char. 71; Evans & Reisz 2007: char. 1; Gates & Sampson 2007: char. 27.

0.absent

1.present

7.Premaxilla, outer (accessory) narial fossa anterior to circumnarial fossa:

Horner et al. 2004: char. 26; Prieto-Marquez 2005: char. 17 modified; Prieto-Marquez et al. 2006a: char. 20; Prieto-Marquez et al. 2006b: char. 65 and 66; Gates & Sampson 2007: char. 28; Godefroit et al. 2008: char. 12 modified.

0.absent

1.present, separated from circumnarial fossa by strong ridge

8.Premaxilla, posterior processes (PM1, PM2) and construction of nasal passages:

Horner et al. 2004: char. 27 modified; Prieto-Marquez 2005: char. 18 modified; Prieto-Marquez et al. 2006a: char. 21 modified; Godefroit et al. 2008: char. 13 modified; Evans Reisz 2007: char. 3; Gates & Sampson 2007: char. 30.

0.posterodorsal premaxillary process short, posterodorsal and posteroventral processes do not meet posterior to external nares, nasal passages not enclosed ventrally, external nares exposed in lateral view

1.posteroventral and posterodorsal processes elongate and join behind external opening of narial passages to exclude nasals, nasal vestibule completely enclosed by tubular premaxillae, left nasal passage divided from right passage

9.Premaxilla, lateral process:

Godefroit et al. 2003: char. 8; Godefroit et al. 2004b: char. 9; Evans & Reisz 2007: char. 6 modified; Godefroit et al. 2008: char. 14.

0.stopping anterior to or at level of lacrimal

1.extending further backward above skull roof

10.Nasal-frontal contact:

Godefroit et al. 2004: char. 18 modified.

0.relatively wide

1.very narrow

2.nasal displaced above frontal

11.Nasal cavity, position:

Weishampel et al. 1993: char. 10 and 12 modified; Norman 2002: char. 8 modified; Godefroit et al. 2003: char. 10 modified; Godefroit et al. 2004a: char. 9, 17 and 19 modified; Godefroit et al. 2004b: char. 13 modified; Horner et al. 2004: char. 33 modified; Suzuki etal. 2004: char. 8 modified; Evans & Reisz 2007: char. 7; Gates & Sampson 2007: char. 38 modified; Godefroit et al. 2008: char. 18 modified.

0.nasals flat posterodorsally and restricted to area anterior to braincase, nasal cavity anteromedial to orbits

1.premaxilla extended posteriorly and nasals retracted posteriorly to lie over braincase in adults resulting in convoluted, complex narial passage and hollow crest that extends above orbit

12.Nasal vestibule, s-loop in the enclosed premaxillary passages anterior to dorsal process of maxilla:

Evans & Reisz 2007: char. 8

0.absent

1.present

13.External naris, surrounding bones:

Weishampel et al. 1993: char. 6 modified; Norman 1998: char. 5; Norman2002: char. 6; Godefroit et al.2003: char. 9; Godefroit et al. 2004a: char. 10 modified; Godefroit et al. 2004b: char. 11 modified; Horner et al. 2004: char. 29; Suzuki et al. 2004: char. 6 modified; Prieto-Marquez 2005: char. 19; Evans & Reisz 2007: char. 4 modified; Godefroit et al. 2008: char. 11 modified.

0.surrounded by both nasal and premaxilla

1.completely surrounded by premaxilla

14.External naris length to basal skull length ratio:

Weishampel et al. 1993: char. 5 modified; Norman 1998: char. 2 modified; You et al. 2003: char. 3 modified; Godefroit et al. 2004a: char. 13 modified; Godefroit et al. 2004b: char. 10 modified; Bolotsky Godefroit 2004: char. 7 modified; Horner et al. 2004: char. 28; Prieto-Marquez et al. 2006a: char. 22a; Prieto-Marquez et al. 2006b: char. 51 modified; Gates & Sampson 2007: char. 32; Godefroit et al. 2008: char. 15.

0.20% or less

1.30% or more

15.External nares, shape of posterior margin:

Horner et al. 2004: char. 41; Prieto-Marquez et al. 2006a: char. 35; Gates & Sampson 2007: char. 43.

0.lunate

1.V-shaped

16.Circumnarial fossa, posterior margin:

Weishampel et al. 1993: char. 7 modified; Norman 1998: char. 6 modified; Godefroit et al. 2004a: char. 14 modified; Godefroit et al. 2004b: char. 12 modified; Bolotsky & Godefroit 2004: char. 6 modified; Horner et al. 2004: char. 31; Prieto-Marquez et al. 2006a: char. 25; Prieto-Marquez et al. 2006b: char. 53 modified; Gates & Sampson 2007: char. 36.

0.absent

1.present

17.Circumnarial fossa, posterior margin structure:

Bolotsky & Godefroit 2004: char. 17 modified; Godefroit et al. 2004a: char. 15 modified; Horner et al. 2004: char. 32; Prieto-Marquez 2005: char. 21; Prieto-Marquez et al. 2006a: char. 26; Prieto-Marquez et al. 2006b: char. 54 modified; Gates & Sampson 2007: char. 37; Godefroit et al. 2008: char. 17 modified.

0.circumnarial fossa absent

1.present, lightly incised into nasals and premaxilla, often poorly demarcated

2.present, well demarcated, deeply incised, and usually invaginated

18.Circumnarial fossa, posterior end position:

Bolotsky & Godefroit 2004: char. 19; Godefroit et al. 2004a: char. 16.

0.circumnarial fossa absent

1.located anterior to anterior end of orbit

2.located above or posterior to anterior end of orbit

19.Hollow nasal crest, shape:

Horner et al. 2004: char. 36; Prieto-Marquez et al. 2006a: char. 30; Prieto-Marquez et al. 2006b: char. 57 and 60 modified; Evans & Reisz 2007: char. 9 and 10 modified.

0.absent

1.present, tubular and elongate

2.present, raised into a large, vertical fan

20.Hollow nasal crest, nasal-posterodorsal process of premaxilla (PM1) contact:

Horner et al. 2004: char. 34; Prieto-Marquez et al. 2006a: char. 28; Prieto-Marquez et al. 2006b: char. 58 modified; Evans & Reisz 2007: char. 17.

0.absent

1.present, anterior end of nasal fits along ventral edge of premaxilla

2.present, premaxilla and nasal meet in a complex, W-shaped interfingering suture

21.Hollow nasal crest, composition of posterior margin of crest:

Weishampel et al. 1993: char. 11 modified; Godefroit et al. 2001: char. 7 modified; Godefroit et al. 2004a: char. 20 modified; Godefroit et al. 2004b: char. 14 modified; Horner et al. 2004: char. 37; Prieto-Marquez et al. 2006a: char. 31; Prieto-Marquez et al. 2006b: char. 61; Evans & Reisz 2007: char. 11 and 16 modified; Godefroit et al. 2008: char. 19 modified.

0.absent

1.present, composed of premaxilla posterodorsal process (PM1)

2.present, composed of nasal

22.Solid nasal crest over snout or braincase (not housing portion of nasal passage):

Weishampel et al. 1993: char. 8 and 9 modified; Bolotsky & Godefroit 2004: char. 15 and 18 modified; Horner et al. 2004: char. 38; Prieto-Marquez 2005: char. 24; Prieto-Marquez et al. 2006a: char. 32; Prieto-Marquez et al. 2006b: char. 55; Gates Sampson, 2007: char. 39.

0.absent

1.present

23.Solid nasal crest, association with posterior margin of circumnarial fossa:

Horner et al. 2004: char. 39; Prieto-Marquez 2005: char. 25; Prieto-Marquez et al. 2006a: char. 33; Gates & Sampson 2007: char. 40; Godefroit et al. 2008: char. 20.

0.absent

1.solid crest present but circumnarial fossa does not excavate side of crest, fossa terminates anterior to solid crest

2.solid crest present, excavated laterally by circumnarial fossa

24.Solid nasal crest, composition:

Horner et al. 2004: char. 40; Prieto-Marquez 2005: char. 26; Prieto-Marquez et al. 2006a: char. 34; Prieto-Marquez et al. 2006b: char. 56 modified; Gates & Sampson 2007: char. 41.

0.absent

1.solid crest present, composed of nasals

2.solid crest present, composed of frontals and nasals

25.Frontal-nasal fontanelle in adults:

New

0.absent

1.present

26.Prefrontal, shape:

Horner et al. 2004: char. 50; Prieto-Marquez et al. 2006a: char. 43; Prieto-Marquez et al. 2006b: char. 33; Gates & Sampson 2007: char. 54.

0.smoothly curved laterally

1.anteriorly broad with square anteromedial corner

27.Prefrontal shape at anterodorsal orbital rim:

Horner et al. 2004: char. 49; Prieto-Marquez et al. 2006a: char. 42; Prieto-Marquez et al. 2006b: char. 34; Gates & Sampson 2007: char. 53.

0.prefrontal lies flush with surrounding elements

1.prefrontal flares dorsolaterally to form thin, everted, wing-like rim around anterodorsal orbital margin

28.Prefrontal, dorsal crest:

Prieto-Marquez et al. 2006b: char. 32.

0.absent

1.present

29.Prefrontal, posterior portion:

Godefroit et al. 2000: char. 7 modified; Godefroit et al.2001: char. 8; Godefroit et al. 2003: char. 13; Godefroit et al. 2004a: char. 22; Godefroit et al. 2004b: char. 16; Godefroit et al. 2008: char. 22; Evans & Reisz 2007: char. 32 modified.

0.oriented horizontally

1.participating in ventrolateral border of hollow crest

30.Prefrontal, medial flange extending posteriorly over dorsal surface of frontal and above prefrontal-postorbital joint in lateral view in adults:

Evans & Reisz 2007: char. 33.

0.absent

1.present

31.Frontal, shape of ectocranial surface:

Godefroit et al. 2003: char. 6 modified; Godefroit et al. 2004a: char. 6 modified; Godefroit et al. 2004b: char. 6 modified; Evans & Reisz 2007: char. 42; Godefroit et al. 2008: char. 7 modified.

0.elongate with ectocranial length/width more than 0.8

1.relatively short, with length/width less than 0.8

2.greatly shortened, length/width ratio less than 0.4

32.Frontal at orbital margin:

Godefroit et al.2000: char. 6; Godefroit et al. 2001: char. 5; Norman 2002: char. 19; Godefroit et al. 2003: char. 3; Bolotsky & Godefroit 2004: char. 21; Godefroit et al. 2004a: char. 3; Godefroit et al. 2004b: char. 5; Horner et al. 2004: char. 57; Suzuki et al. 2004: char. 27; Prieto-Marquez 2005: char. 35; Prieto-Marquez et al. 2006a: char. 50; Prieto-Marquez etal. 2006b: char. 49 modified; Evans & Reisz 2007: char. 39; Gates & Sampson 2007: char. 66; Godefroit et al. 2008: char. 5.

0.forming part of margin

1.excluded by prefrontal-postorbital contact

33.Frontal platform:

Godefroit et al.2000: char. 5; Godefroit et al.2001: char. 5; Godefroit et al. 2003: char. 5; Bolotsky & Godefroit 2004: char. 10; Godefroit et al. 2004a: char. 7; Godefroit et al. 2004b: char. 4; Evans & Reisz 2007: char. 40 and 41 modified; Godefroit et al. 2008: char. 8.

0.deeply excavated frontal platform absent

1.occupying anterior part of frontal in adult

2.extending above anterior portion of supratemporal fenestra

34.Frontals, upward doming over braincase in adults:

Horner et al. 2004: char. 58; Suzuki et al. 2004: char. 25; Prieto-Marquez et al. 2006a: char. 51; Prieto-Marquez et al. 2006b: char. 47; Evans & Reisz 2007: char. 38; Gates & Sampson 2007: char. 67.

0.absent

1.present

35.Supraorbital articulation:

Norman 2002: char. 13 modified; Godefroit et al. 2003: char. 12; You et al. 2003: char. 17; Godefroit et al. 2004a: char. 21; Godefroit et al. 2004b: char. 15; Horner et al. 2004: char. 59; Suzuki et al. 2004: char. 19; Evans & Reisz 2007: char. 34; Gates & Sampson 2007: char. 68; Godefroit et al. 2008: char. 21.

0.freely articulating on orbital rim

1.fused to orbital rim or absent

36.Postorbital, dorsal surface:

Godefroit et al. 2004a: char. 26; Godefroit et al. 2004b: char. 17; Evans & Reisz 2007: char. 37; Godefroit et al. 2008: char. 28.

0.flat

1.thickened to form dorsal promontorium

37.Postorbital, length of squamosal process:

Prieto-Marquez et al. 2006b: char. 37.

0.short, postorbital-squamosal joint reaches point at mid-length of supratemporal fenestra

1.long, postorbital-squamosal joint near level of posterior border of supratemporal fenestra

38.Parietal, shape:

Weishampel et al. 1993: char. 23 modified; Godefroit et al. 2000: char. 3 modified; Godefroit et al. 2001: char. 4 modified; Godefroit et al. 2003: char. 2 modified; Godefroit etal. 2004a: char. 2 modified; Godefroit et al. 2004b: char. 2 modified; Evans & Reisz 2007: char. 46 modified.

0.long, length/minimum width ratio greater than 2

1.less than 2

39.Parietal, sagittal crest:

Horner et al. 2004: char. 69 modified; Prieto-Marquez et al. 2006a: char. 58 modified; Prieto-Marquez et al. 2006b: char. 91 modified; Evans & Reisz 2007: char. 44; Gates Sampson 2007: char. 83 modified; Godefroit et al. 2008: char. 4 modified.

0.straight and level with skull roof or slightly down-warped along length

1.sagittal crest deepens posteriorly (strongly down-warped)

40.Parietal sagittal crest, length:

Horner et al. 2004: char. 70 modified; Prieto-Marquez et al. 2006a: char. 59 modified; Prieto-Marquez et al. 2006b: char. 92 modified; Evans & Reisz 2007: char. 45 modified; Gates & Sampson 2007: char. 84 modified; Godefroit et al. 2008: char. 3.

0.short, less than 2/3 length of parietal

1.long, more than 2/3 length of parietal

41.Squamosals, separationon skull roof:

Horner et al. 2004: char. 63; Suzuki et al. 2004: char. 33 modified; Prieto-Marquez 2005: char. 36; Prieto-Marquez et al. 2006a: char. 54; Prieto-Marquez et al. 2006b: char. 43; Gates & Sampson 2007: char. 73.

0.widely separated

1.squamosals approaching midline, separated by narrow band of parietal

2.squamosals in broad contact with each other

42.Squamosal, medial ramus:

Godefroit et al. 2008: char. 23.

0.lower than paroccipital process

1.higher than paroccipital process

43.Squamosal, height above quadrate cotylus:

Godefroitet al. 2000: char. 8 modified; Godefroit et al. 2001: char. 9 modified; Bolotsky & Godefroit 2004: char. 12 modified; Godefroit et al. 2004b: char. 18 modified; Evans & Reisz 2007: char. 49; Godefroit et al. 2008: char. 23 modified.

0.lateral side relatively low

1.markedly expanded dorsally above cotylus

44.Squamosal, separation of squamosals in posterior view:

Suzuki et al. 2004: char. 33; Evans & Reisz 2007: char. 47.

0.completely separated by parietal

1.extensive Contact between squamosals present at midline

45.Squamosal, shape of posteroventral surface:

Horner et al. 2004: char. 64; Prieto-Marquez 2005: char. 37 modified; Prieto-Marquez et al. 2006a: char. 55; Prieto-Marquez et al. 2006b: char. 42; Evans & Reisz 2007: char. 48; Gates & Sampson 2007: char. 74.

0.shallow exposure in posterior view

1.forming deep, nearly vertical, well-exposed face in posterior view

46.Antorbital fenestra, external opening:

Norman 1998: char. 13; Godefroit et al. 2000: char. 12 modified; Godefroit et al.2001: char. 13 modified; Norman 2002: char. 10 modified; Godefroit et al. 2003: char. 17 modified; You et al. 2003: char. 4; Bolotsky & Godefroit 2004: char. 2 modified; Godefroit et al. 2004a: char. 32 modified; Godefroit et al. 2004b: char. 21 modified; Horner et al. 2004: char. 43; Gates & Sampson 2007: char. 46.

0.present

1.absent

47.Maxilla, number and arrangement of lateral foramina:

Prieto-Marquez et al. 2006b: char. 21.

0.four or more foramina arranged in a subhorizontal row along lateral wall of maxilla

1.three or four foramina variously arranged

48.Maxilla, anterodorsal process:

Weishampel et al. 1993: char. 19 modified; Head 1998: char. 4 modified; Godefroit et al. 2003: char. 19 modified; Bolotsky & Godefroit 2004: char. 9 modified; Godefroit et al. 2004a: char. 34; Godefroit et al. 2004b: char. 23; Horner et al. 2004: char. 42; Suzuki et al. 2004: char. 13 modified; Prieto-Marquez 2005: char. 27; Prieto-Marquez et al. 2006a: char. 36; Prieto-Marquez et al. 2006b: char. 17; Evans & Reisz 2007: char. 19; Gates & Sampson 2007: char. 44; Godefroit et al. 2008: char. 35.

0.separate anterior process that extends medial to posteroventral process of premaxilla to form part of medial floor of external naris

1.anterior process absent, anterodorsal margin of maxilla forming sloping shelf that underlies premaxilla

49.Maxilla, location of large anterior maxillary foramen:

Horner et al. 2004: char. 44; Suzuki et al. 2004: char. 14 modified; Prieto-Marquez 2005: char. 28; Prieto-Marquez et al. 2006a: char. 37; Evans & Reisz 2007: char. 22; Gates & Sampson 2007: char. 47; Godefroit et al. 2008: char. 33.

0.opens on anterolateral body of maxilla, exposed in lateral view

1.opens on dorsal surface of maxilla along maxilla-premaxilla suture

50.Maxilla-lacrimal contact:

Horner et al. 2004: char. 45; Prieto-Marquez 2005: char. 29 modified; Prieto-Marquez et al. 2006a: char. 38; Evans & Reisz 2007: char. 23; Gates Sampson 2007: char. 48.

0.present externally

1.largely covered externally by jugal-premaxilla contact

51.Maxilla-jugal contact:

Norman 1998: char. 10 modified; Kobayashi & Azuma 2003: char. 3 modified; You et al. 2003: char. 15 modified; Horner et al. 2004: char. 46; Prieto-Marquez et al. 2006a: char. 39; Prieto-Marquez et al. 2006b: char. 27; Gates & Sampson 2007: char. 49.

0.restricted to finger-like jugal process on posterior margin of maxilla

1.jugal process of maxilla reduced to short projection but retaining a distinct facet

2.jugal process of maxilla absent, anterior jugal has extensive vertical contact with maxilla anterior to orbit

52.Maxilla, location of apex in lateral exposure:

Godefroit et al. 2000: char. 13 modified; Godefroit et al. 2001: char. 14 modified; Godefroit et al. 2003: char. 18 modified; You et al. 2003: char. 12; Bolotsky Godefroit 2004: char. 8 modified; Godefroit et al. 2004a: char. 31 modified; Godefroit et al. 2004b: char. 22 modified; Horner et al. 2004: char. 47; Prieto-Marquez 2005: char. 30; Prieto-Marquez et al. 2006a: char. 40; Evans & Reisz 2007: char. 21; Gates & Sampson 2007: char. 50; Godefroit et al. 2008: char. 32 modified.

0.well anterior to center

1.at or anterior to center

53.Maxilla, shape of apex in lateral view:

Weishampel et al. 1993: char. 20 modified; Head 1998: char. 3 modified; Kobayashi & Azuma 2003: char. 4 modified; Horner et al. 2004: char. 48 modified; Prieto-Marquez 2005: char. 31 modified; Prieto-Marquez et al. 2006a: char. 41 modified; Prieto-Marquez et al. 2006b: char. 18 modified; Evans & Reisz 2007: char. 20; Gates Sampson, 2007: char. 51.

0.tall and sharply peaked

1.low and gently rounded

54.Maxilla, ectopterygoid ridge on lateral side:

Godefroit et al. 2000: char. 14; Godefroit et al. 2001: char. 15; Godefroit et al. 2003: char. 20; Bolotsky Godefroit 2004: char. 3; Godefroit et al. 2004a: char. 33; Godefroit et al. 2004b: char. 24; Prieto-Marquez et al. 2006b: char. 22; Evans & Reisz 2007: char. 24; Godefroit et al. 2008: char. 34.

0.anteroposteriorly short, ending at half or less length of posterior region of maxilla

1.well developed into lateral and well demarcated border continuous along posterior region of maxilla

55.Maxilla, location of line of alveolar ("special") foramina on medial side:

Prieto-Marquez et al. 2006b: char. 25 modified.

0.located ventral to mid-height of maxilla

1.located dorsal to mid-height of maxilla

56.Ectopterygoid-jugal contact:

Head1998: char. 6; Godefroit et al. 2000: char. 11; Godefroit et al. 2001: char. 12; Norman 2002: char. 17; Kobayashi & Azuma 2003: char. 6; You et al. 2003: char. 20; Horner et al. 2004: char. 51; Suzuki et al. 2004: char. 23; Prieto-Marquez et al. 2006a: char. 44; Evans Reisz 2007: char. 25; Gates & Sampson 2007: char. 55.

0.present

1.absent, palatine-jugal contact enhanced

57.Lacrimal-nasal contact:

Norman 2002: char. 12; Suzuki et al. 2004: char. 16; Evans & Reisz 2007: char. 26.

0.present

1.absent

58.Jugal, expansion of anterior end below lacrimal:

Weishampel et al. 1993: char. 15 modified; Head 1998: char. 5 modified; Norman 1998: char. 9 modified; Norman 2002: char. 14 modified; Kobayashi & Azuma 2003: char. 5 modified; You et al. 2003: char. 19 modified; Bolotsky & Godefroit 2004: char. 1 modified; Godefroit et al. 2004a: char. 27 modified; Godefroit et al. 2004b: char. 19 modified; Horner et al. 2004: char. 52; Suzuki et al. 2004: char. 20 modified; Prieto-Marquez et al. 2006a: char. 45; Evans & Reisz 2007: char. 27; Gates & Sampson 2007: char. 56.

0.dorsoventrally narrow, forms little of the anterior orbital rim

1.expanded dorsoventrally in front of orbit, lacrimal pushed dorsally to lie completely above the level of the maxilla, jugal forms lower portion of orbital rim

59.Jugal, anterior end shape:

Weishampel et al. 1993: char. 14 and 16 modified; Head 1998: char. 7 modified; Godefroit et al. 2000: char. 10 modified; Godefroit et al. 2001: char. 10 and 11 modified; Godefroit etal. 2003: char. 15 and 16 modified; Bolotsky Godefroit 2004: char. 13 modified; Godefroit et al. 2004a: char. 28 modified; Godefroit et al. 2004b: char. 20 modified; Horner et al. 2004: char. 53 and 54 modified; Prieto-Marquez 2005: char. 32; Prieto-Marquez et al. 2006a: char. 46; Gates Sampson, 2007: char. 57; Godefroit et al. 2008: char. 29 modified.

0.with distinct, anteriorly pointed process fitting between maxilla and lacrimal

1.truncated, rounded anterior margin

60.Jugal, development of free ventral flange:

Horner et al. 2004: char. 55; Prieto-Marquez 2005: char. 34 modified; Prieto-Marquez et al. 2006a: char. 48; Evans & Reisz 2007: char. 30; Gates & Sampson 2007: char. 61; Godefroit et al. 2008: char. 31 modified.

0.absent, jugal expands gradually below infratemporal fenestra to meet quadratojugal-quadrate

1.present, jugal dorsoventrally constricted beneath infratemporal fenestra to set off flange anterior to constriction

61.Jugal, ventral flange shape:

Suzuki et al. 2004: char. 21 modified; Evans & Reisz 2007: char. 31 modified.

0.flange absent

1.rounded or lobate