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TABLE 1. List of unambiguous dental synapomorphies in 40 theropod clades illustrated in Figures 3 and 4 and based on a data matrix of 145 dental characters coded in 97 saurischian taxa.

Clade Unambiguous dental synapomorphy
1. Eoraptor + Theropoda Character 4: partial overlap of the first and second premaxillary alveoli in palatal view
2. Dracovenator + Neotheropoda Characters 15, 120: slightly constricted premaxillary tooth row in palatal view; braided oriented enamel surface texture not clearly visible with light
3. Liliensternus + Dilophosaurus + Averostra Character 31: first dentary tooth/alveolus substantially smaller than second and third dentary teeth/alveoli
4. Dilophosaurus + Averostra Characters 56: 14 to 19 mid-crown denticles per five millimeters on the distal carina (DC) of mesial teeth in subadults/adults
5. Averostra Character 15: unconstricted premaxillary tooth row in palatal view
6. Abelisauroidea Characters 8, 9, 45, 46, 51: mesial and distal premaxillary teeth subequal in size than the first six mesial maxillary teeth (or alveoli); salinon-shaped outline of basal cross-section of the crown in the mesialmost tooth; concave surfaces adjacent to the mesial distal carina on the lingual side of the mesial teeth; mesial carina extends to the cervix or just above it in mesial teeth
7. Ceratosauridae Characters 5, 69, 94: overlap of the second and third premaxillary alveoli in palatal view; largest crown in subadults/adults higher than six centimeters; subquadrangular mesial denticles at two-thirds of the crown in lateral teeth
8. Noasauridae Characters 31, 40: first dentary tooth/alveolus subequal size in than second and third dentary alveoli; largest crown in subadults/adults shorter than one centimeter
9. Abelisauridae Characters 3, 4, 13, 25, 91, 99: premaxillary alveoli all mesio-distally oriented; no overlap of the first and second premaxillary alveoli in palatal view; subrectangular premaxillary and maxillary alveoli; distal denticles hooked and apically inclined from distal margin in lateral teeth
10. Megalosauroidea Character 82: mesial carina extending to base of crown or slightly above the cervix in lateral teeth
11. Piatnitzkysauridae Characters 19, 104, 108, 112, 113: 18 to 19 maxillary teeth/ alveoli; distal denticles larger than mesial ones in lateral crowns (DSDI > 1.2); short and poorly developed interdenticular sulci between mid-crown denticles on the distal carina in lateral teeth; tenuous and numerous transverse undulations on the crown surface of lateral teeth
12. Megalosauria Character 53: mesial carina facing labially in mesialmost teeth
13. Megalosauridae Character 28: fewer than 15 dentary teeth/alveoli
14. Megalosauridae more derived than Sciurumimus Characters 5, 56, 108, 109: overlap of the second and third premaxillary alveoli in palatal view; nine to 13 denticles per five millimeters on the distal carina at mid-crown in mesial teeth; short and poorly developed interdenticular sulci between basal and mid-crown denticles on the distal carina in lateral teeth
15. Spinosauridae Characters 2, 7, 8, 11, 12, 14, 15, 22, 23, 25, 30, 33, 45, 51, 63, 70, 76, 82, 110, 141, 142: more than six premaxillary teeth; distal premaxillary teeth smaller than mesial premaxillary teeth; mesial premaxillary and maxillary teeth subequal in size; second premaxillary tooth/alveolus significantly smaller than third and fourth tooth/alveolus; distalmost premaxillary tooth significantly smaller than more mesial teeth; premaxillary teeth anterior to external naris; strongly lateromedially constricted premaxillary tooth rows; first maxillary tooth/alveolus significantly smaller than second tooth/alveolus; procumbent mesial maxillary teeth; subcircular maxillary alveoli; mesialmost dentary teeth significantly larger than more distal ones; terminal rosette of the dentary bearing four teeth; outline of the basal cross-section of mesial teeth subcircular; mesial carina extending well-beneath the cervix in mesial teeth and to the base of crown or slightly above the cervix in lateral teeth; flutes present on the lingual surface of mesial teeth; distal margin of lateral teeth convex, with apex centrally positioned; CBR > 0.75 in lateral teeth; subcircular cross-sectional outline of lateral teeth; flutes on both lingual and labial sides of lateral teeth; root strongly tapered apically and oval to subcircular in cross-section at mid-root
16. Avetheropoda Characters 41, 50, 51: labiolingual compression of the crown weak (0.75 < CBR < 1.2, tooth subcircular) in mesial teeth; mesial carina of mesial teeth slightly twisted, curves onto the mesiolingual surface; mesial carina extends to the cervix or slightly above it in mesial teeth
17. Allosauroidea Characters 5, 46, 55, 56, 87, 94, 108, 112: overlap of the second and third premaxillary alveoli in palatal view; concave surface on the labial and lingual surfaces adjacent to the distal and mesial and distal carinae, respectively, in mesial teeth; nine to 13 mesial and distal denticles per five millimeters in mesial teeth, and nine to 15 in the mesial carina of lateral teeth; subquadrangular mesial denticles at two-thirds height of crown in lateral teeth; short and poorly developed interdenticular sulci between distal denticles at mid-crown in lateral teeth; tenuous or well-visible transverse undulations on the crown surface of lateral teeth
18. Metriacanthosauridae Characters 74, 120: surface centrally positioned on the labial surface of the crown roughly flattened in lateral teeth; irregular and non-oriented enamel surface texture
19. Allosauria Characters 9, 109: distal premaxillary teeth/alveoli subequal in size than the first six mesial maxillary teeth/alveoli; short and poorly developed interdenticular sulci in basal denticles of the distal carina
20. Neovenatoridae Characters 22, 74, 75: first maxillary tooth significantly smaller than second maxillary tooth; surface centrally positioned on the labial surface of the crown roughly flattened in lateral teeth; concave surface adjacent to the distal carina on the labial and lingual surfaces, in lateral teeth
21. Carcharodontosauridae Characters 45, 46, 97: subcircular, ovoid or elliptical outline of basal cross-section of the crown in the mesialmost tooth; concave surface adjacent to the carina absent in mesial teeth; biconvex mesial denticles
22. Coelurosauria Characters 56, 87, 104: more than 20 distal denticles at mid-crown and more than 30 mesial denticles at two-thirds height of the crown in mesial and lateral teeth, respectively; distal denticles larger than mesial ones in lateral crowns (DSDI > 1.2)
23. Tyrannosauroidea + Neocoelurosauria Character 95: mid-crown denticles (DC) on distal carina as long mediodistally as apicobasally, subquadrangular, in lateral teeth
24. Tyrannosauroidea Characters 5, 6, 30, 50, 52, 54: overlap of the second and third as well as third and fourth premaxillary alveoli in palatal view; mesialmost dentary teeth significantly smaller than mid- and distal dentary teeth; mesial carina of mesial teeth strongly twisted, curving onto the lingual surface; distal carina of mesial teeth strongly labially deflected and facing mostly lingually
25. Pantyrannosauria Characters 3, 42, 45, 50, 56, 87: all premaxillary alveoli labio-lingually oriented; important baso-apical elongation of the crown (2.5 < CHR ≤ 3) in mesial teeth; U-shaped outline of basal cross-section of the crown in the mesialmost tooth; mesial carina almost straight and strongly lingually deflected in mesial teeth; fewer than 20 distal denticles per five millimeters at mid-crown in the mesial dentition of subadults/adults, and fewer than 30 mesial denticles per five millimeters at two-thirds height in the lateral dentition
26. Tyrannosauridae Character 4: overlap of the first and second premaxillary alveoli in palatal view almost complete
27. Neocoelurosauria Characters 49, 84: unserrated distal carina in mesial teeth; distal carina extends well-above the cervix in lateral teeth
28. Compsognathidae + Maniraptoriformes Characters 45, 120: subcircular outline of basal cross-section of the crown in the mesialmost tooth; smooth or irregular non-oriented enamel surface texture of the crown
29. Compsognathidae Characters 22, 43, 140: First maxillary tooth significantly smaller than second maxillary tooth; strongly distally recurved mesial teeth; root with convex mesial and distal margins, root significantly larger than base crown
30. Maniraptoriformes Characters 19, 44, 70, 72, 76: more than 19 maxillary teeth; distal margin of the mesial crowns straight in lateral view; weak (i.e., CBR > 0.75) labiodistal compression of the lateral crowns; margin of crown convex, so that the crown apex of lateral teeth is centrally positioned; subcircular cross-sectional outline at the base crown in lateral teeth
31. Ornithomimosauria Characters 18, 25, 26, 73: maxillary teeth absent in the anteriormost and/or most of the posterior portion of the maxilla; maxillary alveoli merged to form an open groove; distalmost maxillary tooth aligned to the anteroventral rim of the antorbital fenestra; mesial margin of lateral teeth slightly convex, almost straight
32. Alvarezsauroidea + Maniraptora Character 32: mid-dentary teeth/alveoli subequal in size than mesial maxillary teeth/alveoli
33. Maniraptora Character 140: root with convex margins, root significantly larger than crown base
34. Therizinosauria Characters 67, 77, 101, 103: important constriction at the cervix in lateral teeth, base of crown occupying 85% or less of largest crown width; mesial carina present in lateral teeth; lower number of denticles apically than at the mid-crown on the mesial and distal carinae in lateral teeth
35. Pennaraptora Characters 19, 25, 142: fewer than 19 maxillary teeth/alveoli; oval to lenticular maxillary alveoli; 8-shaped outline of mid-root in cross-section
36. Oviraptorosauria Character 27: teeth absent in the anteriormost portion of the dentary
37. Paraves Character 72: distal margin of lateral crown slightly concave, roughly straight, or straight, apex positioned at the same level as distal profile
38. Dromaeosauridae Characters 45, 67, 72: D-shaped or J-shaped cross-sectional outline of the base crown in mesial teeth; constriction between crown and root absent in lateral teeth; distal margin of lateral crown strongly concave
39. Troodontidae Characters 20, 29, 39: mesial maxillary teeth significantly smaller than distal maxillary teeth; dentary alveoli merged to form an open groove; constriction between crown and root present in all lateral teeth
40. Avialae Characters 8, 19, 28: mesial premaxillary teeth subequal in size than the first six mesial maxillary teeth; fewer than ten maxillary teeth; fewer than 15 dentary teeth

 

 

 

 

TABLE  2. p-values of the t-test and Mann-Whitney U-test (M-W) for CI and RI values between dental and no-dental characters in five datasets of the theropod skeleton. Significantly similar values between dental and non-dental sets of characters are bolded.

Dataset Clade t-test, ci t-test, ri M-W, ci M-W, ri
Brusatte et al. (2014) Non-avian Coelurosauria 2.14E-10 4.67E-14 6.77E-10 2.26E-15
Carrano et al. (2012) Non-coelurosaur Tetanurae 2.29E-09 5.42E-13 4.61E-10 1.03E-12
Choiniere et al. (2014a) Non-avian Theropoda 0.22025 7.31E-07 0.4483 2.01E-07
Foth and Rauhut (2017) Non-avian Coelurosauria 0.001355 1.66E-07 0.006778 1.69E-07
Lee et al. (2014a) Non-avian Theropoda 0.014723 2.43E-08 0.096904 2.71E-08
Rauhut and Carrano (2016) Ceratosauria 5.47E-09 1.99E-10 4.15E-08 5.93E-10
Tortosa et al. (2014) Ceratosauria 0.015288 0.0088158 0.018854 0.0077152
Wang et al. (2017a) Non-avian Theropoda 0.0027452 9.99E-08 0.0005687 2.19E-08

 

 

 

 

 

TABLE 3. Distribution of dental features in non-avian theropods and their hypothetical functionality, adaptation or causes.

Dental feature Distribution Possible functionality, adaptation or causes
Ziphodonty Ornitholestes, non-alvarezsaurid Alvarezsauroidea, Dromaeosauridae, and non-maniraptoriform theropods other than Allosaurus, Austroraptor, Spinosauridae and Tyrannosauridae Slashing, cutting flesh and defleshing (carnivory)
Folidonty Pelecanimimus and all other Maniraptoriformes other than Ornitholestes, Aorun, Haplocheirus, Ornithomimosauria and Dromaeosauridae Puncturing, tearing apart and shredding fibrous plant fodder and/or small prey (herbivory/omnivory or carnivory)
Pachydonty Allosaurus and mature Tyrannosauridae Bone-crunching (hypercarnivory)
Conidonty Spinosauridae, Ornithomimosauria (Pelecanimimus excluded), Caudipteridae and Austroraptor Piercing and impaling slippery prey (piscivory), or raking vegetation (herbivory); precursor of a rhamphotheca
Basal constriction Chilesaurus, Pelecanimimus and non-dromaeosaurid Maniraptora, with the exclusion of non-alvarezsaurid Alvarezsauroidea, Oviraptorosauria and some Therizinosauria such as Falcarius and Erlikosaurus for the whole dentition; Masiakasaurus, Majungasaurus, Chenanisaurus, Proceratosaurus, Ornitholestes and Halszkaraptor for mesial teeth; Carcharodontosaurinae, Microraptor, Fukuivenator, Falcarius, Erlikosaurus, Incisivosaurus / Protarchaeopteryx and possibly Scansoriopterygidae for lateral teeth  
CBR > 0.75 Spinosauridae, Allosauridae, Tyrannosauridae, Ornithomimosauria, Alvarezsauroidea, Therizinosauria, and Troodontidae for both mesial and lateral teeth Crown strength (resisting higher stresses in different directions)
CHR > 60mm Non-neocoelurosaur Averostra with the exclusion of Abelisauroidea, Piatnitzkysauridae and possibly Baryonychinae, Neovenatoridae and Proceratosauridae Allometric feature
Unserrated crown Limusaurus, Spinosaurinae and Maniraptoriformes other than non-alvarezsaurid Alvarezsauroidea, Therizinosauria, Incisivosaurus, derived Troodontidae, Microraptorinae, Eudromaeosauria and possibly Epidexipteryx for the whole dentition; Sciurumimus, some Coelophysoidea, basal Tyrannosauroidea and Microraptorinae, and most Compsognathidae for mesial teeth; Aorun, Ornitholestes and some Compsognathidae and Dromaeosauridae for lateral teeth Crown simplification
Unserrated mesial carina, serrated distal carina Many theropods from most clades for mesial teeth; Sciurumimus, some megaraptorans, Ornitholestes, Compsognathidae, basal Alvarezsauroidea, a few Dromaeosauridae and many derived Troodontidae for lateral teeth Crown simplification
Concave surface adjacent to carinae Abelisauroidea, Allosaurus, Tyrannosauroidea and many Paraves for mesial teeth; some non-neotheropod Saurischia, Ceratosauridae, non-spinosaurid Megalosauroidea, Metriacanthosauridae, Neovenatoridae and Therizinosauria for lateral teeth Increase in enamel surface, better penetration and withdrawal
J-shaped cross-section Abelisauroidea, basal Tyrannosauroidea, most non-carcharodontosaurid Allosauroidea, and some Eudromaeosauria for mesial teeth; Masiakasaurus and some Troodontidae for lateral teeth Crown strength with linguodistal cutting edges
Salinon-shaped cross-section Abelisauroidea, Allosauridae and some Troodontidae for mesial teeth; some Troodontidae for lateral teeth Crown strength with mesiodistal cutting edges
D-shaped cross-section Metriacanthosauridae, Allosauridae, some Noasauridae, Abelisauridae and Megaraptora, Ornitholestes, Pelecanimimus, Halszkaraptor ? and some Troodontidae for mesial teeth Crown strength with mesiodistal cutting edges
U-shaped cross-section Zuolong, Ornitholestes and most Pantyrannosauria for mesial teeth Crown strength with lingual cutting edges
Figure-8-shaped cross-section Berberosaurus, Metriacanthosauridae, some Megaraptora, Tyrannosauroidea and Troodontidae, and most Dromaeosauridae Crown strength, better penetration and withdrawal?
Mesial carina reaching the cervix In some, if not all, mesial and/or lateral teeth of non-averostran Saurischia, Ceratosauria, Piatnitzkysaurus, Torvosaurus, Spinosauridae, Allosauroidea (excluding most Neovenatoridae), Pantyrannosauria, Eudromaeosauria and Troodon Crown cutting along the whole crown height leading to deeper wounds
Twisted mesial carina Dilophosaurus, Masiakasaurus, Allosauroidea, basal Tyrannosauroidea, and some Abelisauridae and Dromaeosauridae for mesial teeth only; Piatnitzkysaurus, Allosauridae, and some Tyrannosauroidea, Therizinosauria and Dromaeosauridae for lateral teeth Slicing flesh on the crown width causing wide cuts and open wounds (predatory lifestyle?)
Split carina Allosauroidea, Tyrannosauroidea, Segnosaurus, and Dromaeosauridae Trauma, aberrant tooth replacement or genetic factors
Distal carina strongly deflected labially Ceratosauridae, Masiakasaurus, Allosaurus, Sinraptor, Tyrannosauroidea and Dromaeosaurus for the mesial and some lateral teeth; Monolophosaurus, Deinonychus, Richardoestesia and several basal Saurischia, Carcharodontosauria and Dromaeosauridae for mesial teeth; Saltriosaurus, Berberosaurus, Arcovenator, Piatnitzkysauridae and Neovenatoridae for some lateral teeth Causing wide cuts and open wounds, possibly gripping function (predatory lifestyle?)
Hooked denticles Eoraptor, Gojirasaurus, Abelisauroidea, Therizinosauroidea, Eudromaeosauria, Troodontidae (including Anchiornithinae) Slicing flesh, gripping function, possibly removing feather/fur
Small number of large denticles on the carina Therizinosauroidea, Troodontidae, Incisivosaurus, Microraptor and Paronychodon Slicing through resistant structures such as fibrous material (herbivory/omnivory)
Large number of minute denticles on the carina Baryonychinae Tooth simplification, precursor of unserrated crown
Sporadic variation of denticle size Baryonychinae, Nuthetes, Segnosaurus and Richardoestesia Denticle reduction due to tooth simplification
Bilobate denticles Abelisauridae, Megalosauridae, Erectopus, Carcharodontosauridae, Tyrannosauridae Trauma or genetic factor?
Distal denticles larger than mesial denticles Non-averostran theropods, Ceratosaurus, Noasauridae, Abelisauridae, Piatnitzkysauridae, Baryonychinae, Allosaurus, Acrocanthosaurus, basal Coelurosauria, non-tyrannosaurid Tyrannosauroidea, juvenile Tyrannosauridae, non-unenlagiine Dromaeosauridae, and Troodontinae Piercing or slicing function?
Convex distal profile of the crown Abelisauridae, Ceratosaurus, Spinosaurinae, Ornithomimosauria, Alvarezsauroidea, Therizinosauria, and Oviraptorosauria Crown strength
Fluted crowns Tawa, Coelophysis (juveniles), Masiakasaurus, Spinosauridae, an undescribed metriacanthosaurid and Austroraptor for most of/all the dentition; Ceratosaurus, Scipionyx and Velociraptor for the mesial dentition; Sinosaurus, Dilong and most Microraptorinae for the lateral dentition Piercing, gripping and keeping slippery prey
Transverse undulations Eodromaeus, Dracovenator, non-neocoelurosaur Averostra, Falcarius, many eudromaeosaurians and a few derived troodontids; non-neocoelurosaur Averostra when numerous and covering most of the crown Suction minimization, crown strength, or byproduct of growth
Marginal undulations Ceratosaurus, Abelisauridae, non-neocoelurosaur Tetanurae Suction minimization, crown strength, or byproduct of growth
Interdenticular sulci Tawa, non-neocoelurosaur Averostra, Falcarius, many eudromaeosaurians and a few derived troodontids Distributing stresses and/or preventing suction, possibly hosting septic bacteria or helping entrance of venom
Longitudinal ridges Allosaurus, Tyrannosauroidea, Microraptorinae for mesial teeth; Orkoraptor, Alvarezsauroidea, Therizinosauria and Paraves for lateral teeth Crown strength, venom delivery system?
Longitudinal groove Abelisauridae, Paraves Crown strength, venom delivery system?
Basal striations Herrerasauridae, Proceratosaurus Crown strength, byproduct of growth?
Irregular enamel texture Herrerasauridae, Eoraptor, Liliensternus, Sinosaurus, Abelisauroidea (Masiakasaurus excluded), Erectopus, Irritator, Allosaurus, Metriacanthosauridae, Tyrannosaurinae and most of non-dromaeosaurid Neocoelurosauria Crown strength
Braided enamel texture Non-abelisaurid Ceratosauria, non-spinosaurid Megalosauroidea, Carcharodontosauria, Aorun, Segnosaurus and most non-averostran Theropoda, non-neocoelurosaur Coelurosauria and Eudromaeosauria Crown strength
Veined and anastomosed enamel texture Incisivosaurus for the premaxillary dentition; Spinosauridae for the whole dentition Crown strength for particularly high stresses
Procumbent premaxillary teeth Daemonosaurus, Masiakasaurus, Chilesaurus, Similicaudipteryx, Ornitholestes, Epidexipteryx, Archaeopteryx Procumbency: prehension of small to medium-sized prey and/or vegetation (possibly branch raking/stripping)
Procumbent maxillary teeth Dracovenator, Coelophysoidea, Dilophosaurus, Masiakasaurus, Spinosauridae, and Scipionyx for mesial maxillary teeth; Similicaudipteryx, Epidexipteryx, Archaeopteryx and possibly Chilesaurus and Nqwebasaurus for the whole maxillary dentition
Procumbent dentary teeth Herrerasaurus, Daemonosaurus, Daliansaurus, Megapnosaurus, Masiakasaurus, Duriavenator, Spinosaurus, Ornitholestes, Haplocheirus, Incisivosaurus, and some Tyrannosauroidea and Dromaeosauridae for mesial dentary teeth; Chilesaurus, Shenzhousaurus, Similicaudipteryx and Epidexipteryx for the whole dentary dentition
Laterocumbent and retrocumbent teeth Spinosaurinae (laterocumbent teeth); Eoraptor, some Coelophysoidea and basalmost Neotheropoda, and juvenile Limusaurus (retrocumbent premaxillary teeth); Panguraptor, Sciurumimus and several Dromaeosauridae (retrocumbent maxillary teeth) Hold and keep struggling and/or slippery prey, or keep an immobile bite
Partial/complete premaxillary edentulism Partial: Limusaurus (juvenile), Caudipteryx; Complete: Therizinosauroidea, Caenagnathoidea, and Ornithomimosauria more derived than Pelecanimimus Edentulism: paralleled with the development of a rhamphotheca and gastric mill, weight saving demands, abandon of carnivory (herbivory or omnivory)
Partial/complete maxillary edentulism Partial/anteriormost portion of the maxilla: Limusaurus (juvenile) and Erlikosaurus; Partial/posterior portion of the maxilla: Limusaurus (juvenile), basalmost ornithomimosaurs (i.e., Nqwebasaurus, Pelecanimimus), Shuvuuia, Erlikosaurus, Similicaudipteryx, many troodontids, and Epidexipteryx; Complete: Caudipteryx + Caenagnathoidea, and Ornithomimosauria more derived than Pelecanimimus  
Partial/complete dentary edentulism Partial/anteriormost portion of the dentary: Limusaurus (juvenile), Therizinosauroidea, and non-caenagnathoid Oviraptorosauria; Partial/posterior portion of the dentary: Limusaurus (juvenile), non-ornithomimoid ornithomimosaurs more derived than Pelecanimimus, Similicaudipteryx, and possibly Protarchaeopteryx and all Scansoriopterygidae; Complete: Caudipteryx + Caenagnathoidea, Ornithomimoidea  
Complete edentulism All theropods more derived than Eodromaeus for the pterygoid; Limusaurus, Ornithomimoidea and Caenagnathoidea for the whole skull  

 

 

TABLE 4. Most conspicuous dental features in 31 theropod clades. Dental features for important subclades and taxa are also provided in brackets. *small crowns in comparison to the upper and lower jaws’ height.

Clade Dental features
Non-neotheropod Theropoda Small to medium-sized ziphodont dentition; subcircular cross-section of mesial crowns; mesial carina of mesialmost crowns, when present, facing labially and not reaching the cervix; dentary teeth weakly to strongly procumbent; mesial carina, when present, straight and reaching the cervix in some lateral teeth; mesialmost basal striations on the crown (Herrerasaurus); procumbent premaxillary teeth (Daemonosaurus); fluted mesial and lateral teeth (Tawa)
Coelophysoidea Mesialmost teeth unserrated or with unserrated mesial carina; mesial dentition and mesial maxillary dentition with slender, elongated and strongly recurved (i.e., strongly concave distal profile) teeth; diastema between premaxillary and maxillary teeth; constricted tooth-row between premaxilla and maxilla; retrocumbent premaxillary teeth; procumbent mesial maxillary teeth; procumbent mesial dentary teeth (Megapnosaurus and some Coelophysis specimens); fluted mesial and lateral teeth (juvenile Coelophysis)
Non-averostran Neotheropoda (Liliensternus, Zupaysaurus, Sinosaurus, Dracovenator, and Dilophosaurus) Mesial dentary teeth significantly larger than mid- and posterior dentary teeth; terminal rosette of dentary with four to five teeth; mesial carina of mesial teeth denticulated, facing labially and extending basally well-above the cervix; mesial carina of mesial teeth centrally positioned or slightly labially deflected from the mesial margin of the crown; retrocumbent premaxillary teeth; procumbent mesial maxillary teeth; mesial carina of mesial teeth reaching the cervix in some lateral teeth; DSDI>1.2 (Dracovenator and Dilophosaurus)
Non-abelisauroid Ceratosauria  (Berberosaurus, Saltriovenator, and Ceratosauridae) Mesial carina of mesial teeth restricted to the apical portion of the crown and facing labially in mesialmost teeth; lateral dentition with a few strongly labiolingually compressed crown (CBR<0.4); mid-maxillary teeth taller than the dentary height; mesial and lateral crowns with a strongly labially deflected distal carina; labial surface of the crown weakly convex, almost flat, in some lateral teeth; mesial carina of lateral teeth extends to the cervix or slightly above it; concave surface(s) on the lingual and/or labial sides and adjacent to the mesial and/or distal carinae in some crowns; mesial teeth with fluted lingual surfaces (Ceratosaurus)
Abelisauridae Mesial carina reaching the cervix in mesial and lateral teeth; distal profile of crown weakly concave, straight or convex; lateral teeth with mesial and distal carinae on the mid-line of the mesial and distal profile, respectively; irregular enamel surface texture; subrectangular premaxillary and maxillary alveoli; Salinon to J-shaped cross-sectional outline of mesial teeth in most taxa; apically hooked distal denticles in some taxa
Noasauridae Crown height lower than 2 cm; irregular enamel surface texture; mesial carina of lateral teeth reaching the cervix, DSDI>1.2 (Noasaurinae); procumbent mesial dentition, mesial dentary teeth basally constricted, fluted and with a salinon-shaped cross-sectional outline (Masiakasaurus, possibly in Noasaurinae); flutes, hooked distal denticles and constriction between crown and root in some lateral teeth (Masiakasaurus); unserrated teeth and partial edentulism in juveniles, complete edentulism in adults (Limusaurus, possibly in Elaphrosaurinae)
Piatnitzkysauridae Mesial teeth mesiodistally short and elongated, with a lenticular cross-sectional outline at the cervix; mesialmost teeth with a mesial carina facing labially; DSDI>1.2; mesial carina extending above the cervix in mesial and most lateral teeth; distal carina strongly deflected labially, enamel undulations and short to well-developed interdenticular sulci between distal denticles in some teeth; braided enamel texture; hooked distal denticles and mesial carina spiraling mesiolingually and reaching the root in some lateral crowns (Piatnitzkysaurus)
Megalosauridae Mesial teeth mesiodistally short and elongated, with a lenticular cross-sectional outline at the cervix; mesialmost teeth with a mesial carina facing labially; mesial carina extending well-above the cervix in mesial and lateral teeth; short to well-developed interdenticular sulci in between distal denticles in some teeth; braided enamel texture; transverse/marginal undulations in some teeth in most taxa; bilobate mesial denticles and well-visible transverse undulations in some lateral crowns (Megalosaurinae)
Spinosauridae Conidont dentition; strong allometric heterodonty along the premaxillary, maxillary and dentary dentitions, with the largest crowns bore mesially; more than 5 premaxillary teeth; procumbent mesial maxillary teeth; terminal rosette of dentary with four to five teeth; mesial carina reaching the cervix, and extending on part of the root, in most/all teeth; fluted mesial and lateral teeth; veined/anastomosed enamel surface texture; enamel curving basally adjacent to the carinae; large number of minute denticles changing sporadically in size along the carinae (Baryonychinae); unserrated and beaded carinae, laterocumbent teeth, and distal profile of crowns weakly concave, straight or convex (Spinosaurinae)
Metriacanthosauridae Mesial and distal crowns with denticulated mesial and distal carinae extending to the root; D- to salinon-shaped cross-sectional outline at the crown-base in mesialmost teeth; mesial crowns with mesial carinae spiraling mesiolingually and lingually positioned longitudinal groove adjacent to the mesial carina; lateral teeth with flat to concave labial depressions at the crown-base (8-shaped cross-sectional outline of some lateral teeth); short to well-developed interdenticular sulci between distal denticles; irregular enamel surface texture
Allosauridae Pachydont dentition; mesial and distal crowns with denticulated mesial and distal carinae extending to the root, and well-beneath the cervix in some teeth; mesial crowns with lingually positioned longitudinal groove adjacent to the mesial carina; D- to J- and salinon-shaped cross-sectional outline at the crown-base in mesialmost teeth; mesial teeth and mesial maxillary crowns with mesial carinae spiraling mesiolingually; mesial and most lateral teeth with strongly labially deflected distal carina; marginal and transverse undulations well-visible on some crowns; short to well-developed interdenticular sulci in lateral teeth; dentition with a combination of irregular and braided enamel surface texture
Neovenatoridae (with Megaraptora) J-shaped cross-section of mesial teeth with concave surface adjacent to mesial carina on the lingual surface of the crown; concave surfaces on the labial/lingual surfaces and adjacent to the distal carina in some lateral crowns; braided enamel surface texture; mesial carina absent and figure-8-shaped cross-section of lateral crowns (Megaraptor and Orkoraptor)
Carcharodontosauridae Subcircular cross-section in mesialmost teeth; mesial carina of mesial teeth facing labially and not reaching the cervix; mesialmost teeth with strongly labially displaced distal carina; lateral crowns higher than 6 cm; DSDI<0.9 in lateral teeth; mesial carina reaching the cervix in some/most lateral crowns; well-visible marginal and/or transverse undulations in some lateral teeth; short to well-developed interdenticular sulci in lateral teeth; braided enamel surface texture; bilobate mesial denticles in many taxa; weakly sigmoid distal profile with basal half concave and apical half convex (Carcharodontosauridae more derived than Acrocanthosaurus); weak constriction between crown and root in some lateral teeth (Carcharodontosaurinae) ; pronounced marginal undulations adjacent to mesial and distal carinae in lateral teeth (Carcharodontosaurus saharicus)
Non-tyrannosaurid Tyrannosauroidea Mesial teeth significantly smaller than lateral teeth; J- to U-shaped cross-sectional outline of mesial teeth; concave surface adjacent to mesial carina in mesial teeth; DSDI>1.2 in most taxa; some lateral crowns with a strongly labially deflected distal carina and a mesial carina extending above the cervix; interdenticular sulci between distal denticles in some lateral crowns; braided enamel surface texture; basal striations in mesial teeth (Proceratosaurus)
Tyrannosauridae Pachydont dentition; mesial teeth with U-shaped cross-sectional outline and longitudinal ridge centrally positioned on lingual surface; CBR>1.2 in mesial teeth; transitional dentition with spiraling mesial carina and strongly labially deflected distal carina; short to well-developed interdenticular sulci in some teeth; irregular enamel texture and teeth with split mesial carinae in some taxa
Compsognathidae Ziphodont dentition; teeth lower than 1 cm; conidont mesial/mesialmost teeth; distal denticulated carina not reaching the cervix and/or the apex in some lateral teeth; unserrated mesial dentition and lateral dentition with unserrated mesial carina in most taxa; retrocumbent premaxillary teeth (Juravenator); mesial denticulated carina (Sinocalliopteryx)
Ornithomimosauria Unserrated crowns; small crowns*, with crown height lower than 1 cm; conidont dentition made of subsymmetrical isodont crowns (all ornithomimosaurs but Pelecanimimus); posterior portions of maxilla and dentary edentulous (non-ornithomimoid ornithomimosaurs); premaxilla and maxilla fully edentulous (ornithomimosaurs more derived than Pelecanimimus); complete edentulism (Ornithomimoidea); D-shaped mesialmost teeth, constricted mesial and lateral teeth (Pelecanimimus)
Alvarezsauroidea (Aorun, Haplocheirus, and Alvarezsauridae) Crown height lower than 1 cm; small crowns*; unserrated mesial teeth; closely packed mesial and lateral dentition with subsymmetrical (i.e., mesial and distal profiles convex), unserrated and weakly constricted isodont crowns (Alvarezsauridae/Parvicursorinae); faint longitudinal grooves on the apex (Mononykus)
Therizinosauria Folidont dentition made of subsymmetrical isodont crowns with convex mesial and distal profiles; crown height lower than 1 cm; small crowns*; mesial and distal serrated carinae never reaching the cervix; partially edentulous dentary; edentulous premaxilla, mesial and distal serrated carinae extending above the cervix, small number of large typically apically oriented mesial and distal denticles (Therizinosauroidea); Incisiform mesial teeth with a D-shaped cross section, minute denticles, twisted mesial carina, transverse undulations, and longitudinal ridges in some/all lateral teeth (Falcarius); split distal carina, sporadic variation of denticles size, conidont distalmost dentary dentition (Segnosaurus)
Oviraptorosauria Conidont mesial dentition; strong allometric heterodonty, with mesial teeth significantly larger than distal teeth; unserrated mesial crowns; lateral dentition with crown height lower than 1 cm; folidont lateral dentition (Incisivosaurus and Similicaudipteryx); anastomosed enamel surface texture in mesial teeth (Incisivosaurus); partial premaxillary edentulism and complete maxillary and dentary edentulism (Caudipteryx); procumbent maxillary and dentary teeth (Similicaudipteryx); complete edentulism (Caenagnathoidea)
Halszkaraptorinae and Unenlagiinae Large number of small crowns*; unserrated and strongly distally recurved crowns; irregular and non-oriented enamel surface texture; ridged/fluted lateral teeth (Unenlagiinae); ziphodont lateral crowns (Halszkaraptorinae and Unenlagiinae other than Austroraptor); weakly labiolingually compressed lateral teeth (Halszkaraptorinae and Unenlagiinae other than Buitreraptor); more than five closely packed premaxillary teeth and D-shaped mesial teeth (Halszkaraptor /possibly Halszkaraptorinae); conidont dentition, mesial dentary teeth significantly larger than distal ones (Austroraptor); strongly labiolingually compressed lateral teeth with 8-shaped cross-sectional outline at the crown-base (Buitreraptor)
Microraptorinae Ziphodont dentition whose mesial and lateral dentitions include some unserrated crowns; some mesial teeth with a concave surface on the lingual surface and adjacent to the mesial carina; mesial carina not reaching the cervix; some lateral crowns with unserrated mesial carina and fluted/ridged labial surface; labial depression on the crown-base in some lateral teeth; DSDI>1.2 in lateral teeth (all microraptorines other than Microraptor); some constricted crowns in the mesial and lateral dentitions, unserrated mesial carina, and small number of distal denticles in some lateral crowns (Microraptor)
Dromaeosaurinae Ziphodont teeth with serrated mesial and distal carinae in all lateral teeth; J-shaped mesial teeth; mesial dentition with serrated mesial carina spiraling mesiolingually and extending close to the cervix; transverse undulations in some teeth; DSDI>1.2 in lateral teeth (all dromaeosaurines other than Dromaeosaurus); DSDI ≈ 0 or < 0.9, twisted mesial carina in lateral teeth (Dromaeosaurus); retrocumbent maxillary teeth, hooked denticles (Atrociraptor); procumbent dentary teeth (Utahraptor)
Velociraptorinae Ziphodont dentition with serrated mesial and distal carinae in at least some lateral teeth, DSDI > 1.2, mesial carina not reaching the cervix in most lateral teeth (all velociraptorines other than Tsaagan); some lateral teeth with a figure-of-eight-shaped cross-sectional outline of the crown-base (all velociraptorines other than Deinonychus); many taxa with ridged lateral crowns (e.g., Bambiraptor, Velociraptor, Linheraptor, Acheroraptor); some taxa with retrocumbent maxillary teeth (e.g., Bambiraptor, Deinonychus); mesial carina absent/unserrated in all teeth (Tsaagan); hooked distal denticles (Saurornitholestes); mesialmost teeth with fluted labial surface (Velociraptor)
Anchiornithinae Folidont dentition with weakly to strongly distally recurved crowns; crown height lower than 1 cm; mesial dentition unserrated; mesial dentary teeth closely packed; teeth from middle and distal portion of the lateral dentition sparsely spaced; small crowns* (anchiornithines other than Caihon g); unserrated lateral teeth (anchiornithines other than Caihong and Liaoningvenator); mesial denticles and apically hooked denticles in some lateral teeth (Caihong)
Jinfengopteryginae Folidont dentition with fully unserrated teeth; mesial teeth closely packed; small crowns*; dentary teeth resting in an open alveolar groove; posterior portion of maxilla edentulous; dentition with some unconstricted teeth (Jinfengopteryx)
Troodontinae Folidont dentition with distally recurved crowns in the central and distal portions of the lateral dentition; D- to salinon-shaped mesial dentition; mesial teeth closely packed; dentary teeth resting in an open alveolar groove; fully unserrated dentition in many taxa (e.g., Mei, Xixiasaurus, Urbacodon, Gobivenator, Byronosaurus); heterodont lateral dentition made of folidont and ziphodont crowns in many basal forms (e.g., Xixiasaurus, Sinovenator, Jianianhualong. Byronosaurus); some lateral teeth with a small number of large distal denticles in derived forms (e.g., Sinornithoides, Troodon, Zanabazar, Saurornithoides); mesial denticulated carina (Troodon, Pectinodon); interdenticular sulci and transverse undulations in some teeth (Troodon)
Scansoriopterygidae Conidont dentition; unserrated teeth; strong allometric heterodonty, with mesial teeth significantly larger than distal ones; procumbent premaxillary and dentary teeth; maxilla and dentary partially edentulous

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