Abstract
Full Text
The Evolution of Dinosaurs
Paul C. Sereno

Supplementary Material

The calibrated cladogram (Fig. 2) is based on the following nine cladistic datasets, which are summarized in Table 1 and described in more detail elsewhere (1). Dataset 1 provides the phylogenetic framework at the base of Dinosauria for datasets 2-9 that compare taxa within major dinosaurian clades. Dataset 9 covers characters at the base of Aves, a terminal taxon in dataset 8.

Missing data, inapplicable comparisons, and coding complexity are major limiting factors when considering a broad array of extinct terminal taxa at low taxonomic levels. Necessary assumptions include the proximity of outgroups and the monophyly of ingroups. These are made strategically in the following datasets to focus on major phylogenetic questions.

Character-states are coded as follows: 0 = primitive state; 1-4, derived states; ?, missing data; X = topological homolog absent. When the basal condition of a character for a terminal taxon is ambiguous, it is scored as polymorphic. All character-states are weighted equally, and most characters are binary and unordered.

Multistate characters are usually unordered; when states are linked by a known developmental or growth trajectory, as in the size of a cranial horn, a step matrix is used that allows 1-step truncation to any lower state. In each analysis (Table 1), two outgroups were used with topological constraints that ensured successively more remote placement relative to ingroup taxa. Minimum-length trees were determined by maximum-parsimony (2). The characters are listed below under ingroup clades under delayed-transformation optimization.

1--Basal Dinosauria
This dataset includes 146 characters. Successively more remote outgroups include Marasuchus and a dinosauromorph ancestor (the latter based on Lagerpeton, Pterosauria, and Crurotarsi) (3). Ingroups include 13 dinosaurian subgroups.

Characters and Character-States
Dinosauria
1. Postfrontal: present (0); absent (1).
2. Frontal participation in supratemporal fossa: absent (0); present (1).
3. Pterygoid-ectopterygoid articular relation: ectopterygoid ventral (0); ectopterygoid dorsal (1).
4. Quadrate head, lateral exposure: absent (covered by squamosal) (0); present (1).
5. Posttemporal opening, size: fenestra (0); foramen (1).
6. Dorsosacral (3 sacrals): present (0); absent (1).
7. Ossified, paired sternal plates: absent (0); present (1).
8. Deltopectoral crest, length: 30% or less (0), or 35 percent or more (1), of humeral length.
9. Manual digit IV, strength: subequal to digits II and III with terminal ungual (0); narrower than digits II and III without terminal ungual (1).
10. Brevis fossa: absent (0); present (1).
11. Femoral greater trochanter, shape: rounded (0); angular (1).
12. Femoral medial tuberosity, size: large (0); small (1).
13. Cnemial crest on tibia: absent (0); present (1).
14. Astragalar ascending process: absent (0); present (1).
15. Astragalar anterolateral process, orientation of contact with calcaneum: ventral (0); lateral (1).
16. Calcaneal medial process, size: broad (0); rudimentary (1).
17. Distal tarsal 4 heel, depth: deep (0); shallow (1).
18. Metatarsal IV shaft axis, curvature (anterior view): straight (0); sigmoid (1).
Ornithischia
19. Premaxillary tooth number: 4 (0); 3 (1); 5 (2); 6 (3); 7 (4).
20. Maxillary/dentary teeth, crown shape: recurved (0); subtriangular (1); lanceolate (2).
21. Maxillary/dentary teeth, marginal ornamentation: serrations (0); denticles (1).
22. Maxillary/dentary teeth, position of largest tooth: anterior end (0), or center (1), of tooth row.
23. Dentary coronoid process: absent (0); present (1).
24. External mandibular fenestra, length: more (0), or subequal to or less (1), than maximum depth of dentary ramus.
Lesothosaurus + Genasauria
25. First premaxillary tooth, position: adjacent to midline (0); inset posteriorly the width of one or more crowns (1).
26. Premaxillary palate, depth: deep and narrow (0); shallow and broad (1).
27. Premaxillary posterolateral process, length: short (0); long (1).
28. Ventral margin of antorbital fossa, inclination: posteroventral (0); horizontal (1).
29. Antorbital fossa and fenestra, size: large, fossa adjacent to maxilla-nasal suture (0); small, fossa separated from maxilla-nasal suture (1).
30. Palpebral: absent (0); present (1).
31. Predentary: absent (0); present (1).
32. Dentary symphysis, shape: V-shaped (0); spout-shaped (1).
33. Iliac preacetabular process, shape: tab-shaped (0); strap-shaped (1); subtriangular (2); semicircular (3); crescentic (4).
34. Iliac preacetabular process, length: distal end is posterior (0), or anterior (1), to distal end of pubic peduncle.
35. Pubic shaft orientation: anteroventral (0); vertical (1); posteroventral (2).
36. Pubic shaft shape: blade-shaped (0); rod-shaped (1).
37. Pubic symphysis length: along entire pubic blade (0); at distal end only (1).
38. Puboischial symphysis: absent (0); present (1).
39. Puboischial contact below acetabulum, depth: deep (0); shallow (1).
40. Obturator opening in pubis, form: foramen (0); notch (1).
41. Prepubic process: absent (0); present (1).
42. Ischial blade shape: tapering (0), or expanding (1), distally.
43. Femoral anterior trochanter, form: prominent crest (0); vertical flange (1); vertical ridge (2).
44. Fourth trochanter, shape: aliform (0); pendant (1), trapezoidal (2).
45. Tibial posteromedial flange, lateral extension: does not reach fibula (0); extends posterior to medial margin of fibula (1); extends posterior to entire distal end of fibula and calcaneum (2).
46. Astragalar lateral facet for fubula: present (0); absent (1).
47. Pedal digit V phalanges: present (0); absent (1).
48. Metatarsal V length: 40 to 50% (0), or less than 25% (1), of metatarsal III length.
49. Distal tarsal 4 heel: present (0); absent (1).
50. Ossified epaxial tendons: absent (0); present (1).
51. Gastralia: present (0); absent (1).
Genasauria
52. Maxillary buccal emargination: absent (0); present (1).
53. Dentary coronoid process, depth: approximately 35% or less (0), or 50% or more (1), of the depth of the dentary at midlength.
54. Pubic peduncle, shape of distal end (lateral view): expanded (0); tapering (1).
Neornithischia
55. Premaxilla-maxilla diastema: absent (0); present (1).
56. Enamel on crowns of maxillary and dentary teeth, distribution: symmetrical (0); asymmetrical (1).
57. Predentary size: less (0), or equal to (1), the length of the premaxillary alveolar margin.
58. Anterior trochanter form: blade-shaped (0); finger-shaped (1).
59. Iliac acetabular flange: present (0); absent (1).
60. Iliac supraacetabular rim: present (0); absent (1).
61. Ischial peduncle of ilium, form: ventrally (0), or ventrally and laterally (1), projecting process.
Saurischia
62. Subnarial foramen: absent (0); present (1).
63. Jugal-lacrimal articular relation: lacrimal overlaps jugal (0); jugal overlaps lacrimal (1).
64. Jugal posterior process, shape: tapered (0); forked (1).
65. Epipophyses on mid- and posterior cervical vertebrae: absent (0); present (1).
66. Hyposphene-hypantrum articulation in dorsal vertebrae: absent (0); present (1).
67. Mid-cervical rib form: short, posteroventrally inclined (0); long, parallel to cervical column (1).
68. Distal carpal 5: present (0); absent (1).
69. Manual length (measured along digit II or III, whichever is longest): 20-30% (0), approximately 40% (1), or 50-70% (2) length of humerus + radius.
70. Manual digit I, phalanx 1 length: shorter (0), or equal to or longer (1), than metacarpal I.
71. Astragalar ascending process, shape: quadrangular (0); wedge-shaped (1); plate-shaped (2).
72. Metatarsals II-IV, form of basal articulation: nonoverlapping (0); overlapping II on III on IV (1).
Sauropodomorpha
73. External naris size: small (0); large (1).
74. Maxilla borders external nares: present (0); absent (1).
75. Narial fossa, ventral width: narrow, above subnarial foramen when present (0); deep, including subnarial foramen when present (1).
76. Premaxillary posterolateral process, articulation: lateral aspect of snout (0); dorsal aspect of maxillary anteromedial process (1).
77. Anterior maxillary foramen: absent (0); present (1).
78. Antorbital fossa, posterior portion of medial wall: present (0); absent (1).
79. Supra-jugular foramen: absent (0); present (1).
80. Proximal carpals (and distal carpal 4): present (0); very reduced or absent (1).
81. Ilium, pubic peduncle length: less (0), or more (1), than twice the distal width of the peduncle.
82. Ilium, axis of the pubic peduncle: straight (0); arched (1).
83. Ilium, ventral acetabular flange: present (0); absent (1).
84. Astragalus, fibular facet orientation: dorsolateral (0); lateral (1).
85. Pedal digit I, ungual length: shorter (0), or longer (1), than other pedal phalanges.
86. Metatarsal V, proximal shaft width: narrow (0); expanded transversely (1).
Theropoda
87. Ectopterygoid fossa: absent (0); present (1).
88. Intramandibular joint: absent (0); present (1).
89. Cervical epipophyses, shape: crest or rugosity (0); prong-shaped process (1).
90. Internal cavitation of centra and long bones: moderate (0); extreme (1).
91. Metacarpals I-III, intermetacarpal articular facets: absent (0); present (1).
92. Metacarpals I-III, asymmetrical extensor depressions: absent (0); present (1).
93. Iliac brevis fossa form: shallow (0); arched (1).
94. Ischial obturator process: absent (0); present (1).
95. Pubic blade, distal width: subequal to (0), or 65% or less than (1), proximal width of blade.
Herrerasauridae + Neotheropoda
96. Axial intercentrum width: less (0), or more (1), than maximum width of axial centrum.
97. Distal caudal prezygapophyses: short (0); elongate (1).
98. Scapular blade, length versus distal width: less (0), or more (1), than 3 times distal width.
99. Manual digits I-III, penultimate phalanx (digits II, III) length and ungual (digits I-III) form: shorter or subequal to preceding phalanx, short moderately recurved unguals (0); longer than preceding phalanx, long strongly recurved unguals (1).
100. Metacarpals IV and V, diameter: short (0); vestigial, less than 50% diameter of metacarpal III (or metacarpal II) (1).
101. Pubic foot: absent (0); present (1). (loss of broad blade-shaped distal end)
102. Femoral distal end, anterior attachment depression: absent (0); present (1).
Herrerasuridae
103. Intramandibular joint polarity: (0) splenial convex (0); splenial concave (1)
104. Femur, proximal shaft, anterolateral margin: rounded (0); crested (1).
Staurikosaurus + Chindesaurus
105. Iliac blade, inclination of dorsal margin: horizontal (0); posteroventrally inclined (1).
106. Iliac preacetabular process, form of ventral margin: rounded (0); everted (1).
Neotheropoda
107. Palatal teeth: present (0); absent (1).
108. Premaxilla-nasal suture: V-shaped (0); W-shaped (1).
109. Medial premaxillary foramen: absent (0); present (1).
110. Nasal posterolateral process: absent (0); present (1).
111. Antorbital fossa, size: anteroposterior diameter greater than the anteroposterior diameter of other skull openings (0), or greater than any diameter of other skull openings (1).
112. Promaxillary fenestra and antrum: absent (0); present (1).
113. Lacrimal crest with pneumatic excavation: absent (0); present (1).
114. Lacrimal ventral process with flange: absent (0); present (1).
115. Squamosal anterior process, orientation (lateral view): anterior (0); anterodorsal (1).
116. Palatine anterior process, shape: tapered distally (1); expanded distally (1).
117. Exoccipital-opisthotic, participation in basal tubera: absent (0); present (1).
118. Laterosphenoid, head articulation: frontal and postorbital (0); postorbital only (1).
119. Basisphenoid fontanelle: absent (0); present (1).
120. Prearticular-angular foramen: absent (0); present (1).
121. Cervical vertebrae (postatlantal), pleurocoels (anterior): absent (0); present (1).
122. Axis, neural canal diameter: more (0), or less (1), than 25% centrum diameter.
123. Axis, prezygapophyses, shape: low process (0); tab-shaped process (1).
124. Axis, transverse process, strength: low prominence (0); cylindrical process (1).
125. Cervical (postatlantal) centra, articular surfaces: amphicoelous (0); marked opisthocoely (1).
126. Axis, intercentrum length: 25% (0), or 50% (1), axial centrum length.
127. Caudosacrals 1 and 2: absent (0); present (1).
128. Caudosacral ribs, attachment position: along ventral margin (0), or rises to a posterodorsal corner (1), of postacetabular process.
129. Anterior caudal neural spines, anterior flange for interspinous articulation: absent (0); present (1).
130. Distal carpal 1, distal articulation: metacarpal I (0); metacarpals I and II (1).
131. Manual digits and metacarpals, longest: digit III, metacarpal III (0); digit II, metacarpal II (1).
132. Manual digit V: present (0); absent (1).
133. Metacarpal I length: longer (0), or shorter (1), than phalanx 1 or ungual of digit I.
134. Ischial distal end, anteroposterior dimension: less (0), or more (1), than greatest width of either ischial peduncle (i.e., "foot" present).
135. Pubic foot, shape of symphyseal area: distal margin only (0); broad median contact (1).
136. Tibia, proximal end, fibular crest: absent (0); present (1).
137. Cnemial crest form: low (0); prominent (1).
138. Tibial shaft proportions, transverse versus anteroposterior: subequal (0); transverse width 140-150% anteroposterior width (1).
139. Fibular mid-shaft, anteroposterior width: 40% (0), or 10-25% (1), of the anteroposterior width of the proximal end.
140. Astragalar crest (ascending process to posterolateral corner): absent (0); present (1).
141. Astragalar posteromedial crest: absent (0); present (1).
142. Metatarsal I length: more (0), or less (1), than 50% metatarsal II length.
143. Metatarsal I, location of articulation on metatarsal II: medial side of proximal end (0); posteromedial side halfway down shaft (1).
144. Metatarsal IV distal end and proximal phalanx base, proportions: broader than tall (0); taller than broad (1).
145. Metatarsal V shaft axis: straight (0); curved or sigmoid (1).
146. Metatarsal V shaft width: robust (0); slender (1).

Data Matrix
Outgroups
Dinosauromorph ancestor
000000?0000000000000000?0?0000002000000000?0X0000000X0?0?X000000000000X00?00000000000000?000?000?00000X00000000000000000000000000?0?00X0X0000?0000
Marasuchus ?????0?0?000000000?000?????0????000000000000000000?0?000?X000???00????X0??????00000000??X0??X000000??0?000?????0??????0?000?00000????0X0X000000?00
Ingroups
Pisanosaurus ????????????11X1?1???111??????????00?00?0???10?????10??0??????????????00????????0??1??????????????????????????????????????????????????X0000?000???
Lesothosaurus
111111?1?11111??01111111111111111121111111112101111000000000000000??00200000000?000?0000X00000X0000000X00010000000000000000000100?0000X0000??0000?
THYREOPHORA
11111111111111111141111111111111112111111111211111111100000000X000000020000000000000000000000000000000X0001000000000000000000000000000X00000000000
ORNITHOPODA
111111111111111111211111111111111121111111112111111111111111100000000020000000000000000000000000000000X0001000000000000000000000000000X00000000000
MARGINOCEPHALIA
11?11111?11111111111111111111111112111111111211111111111111110X000000020000000000000000000000000000000X0001000000000000000000000000000X00000000000
PROSAUROPODA
1111111111111111111210000000000020000000000000100000X000X?00011111111111111111111111110000000000000000X0001000000000000000000000001000X00000000000
SAUROPODA
11011111101111X1X00210010000000041000000000X0010X000X000X?11011111110010111111111111110000000000000000X00010000000000000000010000X0000X00000000000
Eoraptor
1111?101111111?1110010000000000020???0??000000???0?0X000X?0001111?11111?000000?000??00111111111??0000000000001000000??0000??0?000?0001X0000?000000
Herrerasaurus
111111?111111111110010000010000000100000000000100000X000X?00011111112211000000?0000000?11111X111111111110010?0000000000000000000000000000000000000
Staurikosaurus
?????????11111????????00??????000000000?00000????00?X0?0X?000?????1???1?????????000????1?1??0?1?111???1111????????????????????000????000000???????
Chindesaurus
?????????111111??????????????????0????????0?00???????0????000?????????1?????????0000?????1??1???????????11??????????????????0?00???????0?0?00?????
CERATOSAURIA
1111111111111111110010000000000031000000001010000000X000X?1001111111221111010000001000111111111111111100001111111111111111111111111111111111111111
TETANURAE
1111111111111111110010000000000031000000001010000000X000X?1001111111220111010000001000111111111111111100001111111111111111111111111111111111111111

2--Thyreophora
This dataset includes 118 characters in 17 thyreophoran taxa. Successively more remote outgroups include Neornithischia and Lesothosaurus.

Characters and Character-States
Thyreophora
1. Jugal orbital ramus, depth versus transverse breadth: deeper (0); broader (1).
2. Parasagittal row of keeled scutes to each side of the midline on the dorsal aspect of the trunk: absent (0); present (1).
3. Lateral rows of scutes on the dorsal aspect of the trunk: absent (0); present (1).
Emausaurus + Scelidosaurus + Eurypoda
4. Dentary tooth row (and anterior edentulous margin), form (lateral view): straight (0); sinuous (1).
5. Palpebral shape: rod-shaped (0); plate-shaped (1).
6. Metacarpals I and V length: substantially shorter than (0), or subequal to (1), metacarpal III.
7. Manual and pedal unguals: claw-shaped (0); hoof-shaped (1).
Scelidosaurus + Eurypoda
8. Antorbital fossa size: large (0); small (1); absent (2).
9. Palpebral articulation, form: mobile contact with prefrontal (0); interdigitating contact with prefrontal, frontal and postorbital (1).
10. Quadrate condyle, shape: symmetrical (0); medial side larger (1).
11. Pterygovomerine keel, maximum depth: less (0), or more (1), than 50% of snout depth.
12. Basisphenoid length: longer (0), or subequal to or shorter (1), than the basioccipital.
Eurypoda
13. Anterior and posterior supraorbitals: absent (0); present (1).
14. Quadrate condyle, inclination of articular surface (posterior view): horizontal (0); ventromedially inclined at approximately 45 degrees (1).
15. Quadrate lateral ramus: present (0); absent (1).
16. Pterygovomerine keel, length: less (0), or more (1), than 50% of palate length.
17. Dentary symphysial ramus, width: more (0), or less (1), than half of the maximum depth of the mandibular ramus.
18. Premaxillary tooth count: 6 (0); 5 (1); 7 (2).
19. Atlantal neural arch and intercentrum, articulation: open (0); coossified (with maturity) (1).
20. Scapular blade shape: distally expanded (0); parallel-sided (1).
21. Iliac preacetabular process length: less (0), or more (1), than 50% of the length of the iliac blade.
22. Iliac preacetabular process, lateral deflection: 10-20 degrees (0); 45 degrees (1).
23. Ischial blade shape: distally expanded (0); distally tapering (1).
24. Femoral fourth trocanter, form: pendant (0); crest-shaped (1).
25. Femoral anterior trochanter: separated by narrow cleft (0); coossified with greater trochanter in the adult (1).
26. Pedal digit IV phalangeal number: 5 (0); 4 or less (loss of at least one nonterminal phalanx) (1).
27. Metatarsal arrangement: compact (0); spreading (1).
28. Metapodial length: more (0), or less (1), than 30% of propodial length.
Stegosauria
29. Oval fossa on pterygoid ramus of quadrate: absent (0); present (1).
30. Quadrate head, shape: rounded (0); subrectangular (1).
31. Dorsal neural arch pedicel, height: less (0), or 150% or more (1), than centrum height.
32. Mid-dorsal transverse processes, orientation: less (0), or more (1), than 50ƒ above the horizontal.
33. Anterior dorsal neural canal, size: less (0), or more (1), than 50% of the dorsoventral diameter of the centrum.
34. Anterior caudal neural spine end, shape: transversely (0), or anteroposteriorly (1), flattened.
35. Distal caudal centra, proportions: length greater than (0), or equal to (1), height.
36. Ossified epaxial tendons: present (0); absent (1).
37. Scapular acromion, shape: subtriangular (0); subquadrate with anterodorsal corner (1).
38. Triceps tubercle on humerus: subtle or absent (0); prominent with descending ridge (1).
39. Proximal carpals, form: ovoid (0); block-shaped (1).
40. Intermedium-ulnare articulation: free (0); fused (1).
41. Distal carpals: present (0); absent (1).
42. Pubic acetabular surface, orientation: dorsolateral (0); lateral (1).
43. Postpubic process length: less than 100% (0), 200% (1), or more than 200% (2) of acetabular diameter.
44. Pedal digit I: present (0); absent (1).
45. Pedal digit III, phalangeal number: 4 (0); 3 or fewer (1).
46. Parasagittal osteoderms near midline, prominence: low (0); hypertrophied as plates or spines (1).
47. Parascapular spine: absent (0); present (1).
Stegosauridae (Dacentrurus + Stegosaurinae)
48. Sacral intercostal fenestrae: present (0); closed by costal fusion (1).
49. Femoral length: less than 100% (0), or 150% or more (1), of humeral length.
Stegosaurinae
50. Humeral distal end, width: 30% (0), or 50% (1), of humeral length.
51. Ischial shaft, profile of dorsal margin: straight (0); angle near mid-shaft (1).
Ankylosauria
52. Occiput, maximum width: less (0), or more (1), than maximum height.
53. Antorbital fenestra: present, open (0); absent, closed by maxilla, lacrimal, and jugal (1).
54. Supratemporal fenestra: present, open (0); absent, closed by postorbital, squamosal and parietal (1).
55. Jugal-postorbital bar, width: narrower (0), or broader (1), than laterotemporl fenestra.
56. Quadratojugal, orientation of external surface: lateral (0); posterior (1).
57. Nasal septum dividing narial passage: absent (0); present (1).
58. Quadrate shaft, orientation: approximately vertical (0); inclined approximately 45ƒ anteroventrally (1).
59. Pterygovomerine keel, ventral margin: above (0), or level with (1), maxillary alveolar margin.
60. Pterygoquadrate ramus, depth: deep (0); narrow (1).
61. Space between palate and braincase: open (0); very constricted or closed (1).
62. Accessory ossification separating antorbital and orbital spaces: absent (0); present (1).
63. Fusion and dermal sculpturing of skull roof (except ventral margin of premaxilla and maxilla and posterior portion of the quadratojugal): absent (0); present (1).
64. Jaw articulation, position: posterior (0), or medial (1), to adductor fossa.
65. Elongate, keeled mandibular osteoderm: absent (0); present (1).
66. Predentary ventral process, length: prong-shaped (0); rudimentary eminence (1).
67. Maxillary/dentary crowns, band-shaped cingulum: absent (0); present (1).
68. Atlantal neural arches, median contact above neural canal: absent (0); present (1).
69. Three sacrodorsals with long ribs attaching to the ventral aspect of the iliac preacetabular process: absent (0); present (1).
70. Anterior caudal vertebrae, length of transverse processes: subequal to (0), or approximately twice (1), the height of the neural spine.
71. Distal chevron shape, mutual contact: tongue-shaped, isolated (0); inverted T-shape, ends in contact (1).
72. Sternum with shaft-shaped posterolateral process: absent (0); present (1).
73. Scapular acromion, orientation: coplanar with blade (0); everted (1).
74. Acetabular fenestra: open (0); closed (1).
75. Postpubic process, length: more (0), or less (1), than 50% of ischial length.
76. Pospubic process, shape: rod-shaped (0); strap-shaped (1).
77. Two U-shaped cervical collars composed of contiguous keeled scutes: absent (0); present (1).
78. Mosaic of small osteoderms between larger osteoderms and on the ventral surfces of the neck, trunk, and proximal portions of the limbs: absent (0); present (1).
Nodosauridae
79. Snout low: maximum preorbital depth less (0), or more (1), than twice maximum preorbital length.
80. Premaxillary palate, shape: subtriangular (0); oval (1); subquadrate (2).
81. Occipital condyle, form: crescentic (0); hemispherical (ventrally deflected) (1).
82. Occipital condyle, composition: basioccipital and exoccipitals (0); basioccipital only (1).
83. Posterior margin of pterygoid, position: anterior to (0), or in transverse alignment with (1), the ventral margin of the pterygoid ramus of the quadrate.
84. Scute pattern on dorsal skull roof: large median interorbital and internarial scutes (0); paired interorbital and internarial scutes (1).
85. Dentary ventral margin: straight (0); sinuous (1).
86. Scapular blade, anteroposterior width of base: subequal to (0), or at least 25% less than (1), proximal width at glenoid.
87. Scapular glenoid, orientation: facing posteroventrally and laterally (0); facing posteroventrally (1).
88. Coracoid shape: subquadrate (0); subrectangular (1).
89. Coracoid glenoid, size: subequal to (0), or approximately half of (1), scapular glenoid.
90. U-shaped pectoral collar composed of contiguous keeled scutes: absent (0); present (1).
Ankylosauridae
91. Interpremaxillary notch: absent (0); present (1).
92. Accesssory dermal ossifications forming lateral margin of external nares: absent (0); present (1).
93. Accessory dermal ossifications on posterodorsal and posteroventral corners of the skull roof: absent (0); present (1).
Minmi + Shamosaurus + Ankylosaurinae
94. Skull width: less than (0), equal to (1), or greater than (2), maximum skull length.
95. Snout with lateral sinus: absent (0); present (1).
96. Premaxillary teeth: present (0); absent (1).
97. Hypaxial ossified tendons on distal caudals: absent (0); present (1).
98. Tail club composed of 2 pairs of large ossifications (anterior pair largest): absent (0); present (1).
Ankylosaurinae
99. Snout profile: level with (0), or arching above (1), the posterior skull table.
100. Premaxillary posteroventral rim: poorly developed (0); obscures anteriormost maxillary teeth (lateral view) (1).
101. Premaxillary rim, position of posterior end: in line with (0), or shifted lateral to (1), the maxillary tooth row.
102. Maxillary tooth rows, anterior separation: narrow (0); broad (1).
103. Respiratory passage, shape: straight (0); S-shaped (1).
104. Postocular (jugl-postorbital) wall: absent (0); present (1).
105. Posteroventral dermal plate, position: posterior (0), or posteroventral (1), to orbit.
Other ankylosaurines
106. Cranial acessory dermal plates, size: moderate (0); hypertrophied (1).
107. Dentary ramus, location of maximum depth: posterior end (0); mid length (1).
108. Coronoid height: moderate (0); low (1).
109. Posteriormost caudal pre- and postzygapophyses, length: extend over less (0), or more (1), than half of the adjacent centrum.
110. Distal caudal postzygapophyses, form: short, wedge-shaped (0); long, tongue-shaped (1).
111. Distal hemal arches, mutual contact: absent (0); present (1).
112. Sternal plates, median contact: open (0); coossified (1).
113. Humeral deltopectoral crest, orientation: anteriorly curved (0); transverse (1).
114. Iliac postacetabular process, length: longer (0), or shorter (1), than acetabular diameter.
115. Ischial acetabular margin, form: concave (0); convex (1).
116. Ischial shaft orientation: posteroventral (0); subvertical (1).
117. Pubis size, participation in acetabulum: small, participates (0); rudimentary, nearly excluded (1).
118. Tibia, maximum distal width: less (0), or greater (1), than maximum width of proximal end.

Data Matrix
Outgroups
Lesothosaurus
00000000000000000000000000000000000000000000000000000000000000000000000000000000000X000000000000000000000X000000000000
NEORNITHISCHIA
00000000000000000100000000000000000000000000000000000000000000000000000000000000000X00000000000000000000XX000000000000
Ingroups
Scutellosaurus
1110000000?0000?0000000000000000000000???000000?00000000??????00?00000?000000000000X00000000000000000000XX00000?000000
Emausaurus
1111111000?0000?01??????????00000????????????00????00000000000000000000??????000000X0????0000000??000000XX0???????????
Scelidosaurus
111111111111000000?0000000000000000000000000000000000000000000000000000000000000000X00000000000000000000XX0?000?000000
Huayangosaurus
1110?111111111111211111111111111111111111111111000000000000000000000000000000000000X00000000000000000000XX00000?000000
Dacentrurus
?1?????????????????111111111??1111?1?111111111?1100?????????????????000??00000???????00000??????????????X??0????0?0000
Toujiangosaurus
???0???????1?11?1??111?11?????111?1111???????11111100000??????0???1?00???0000000000X000000?0000?00??????XX00????000000
Lexovisaurus
????????????????????11111111??111111111111111111111?????????????????0000000000???????00000??????00??????X?00000?000000
Other stegosaurines
11001111111111111X11111111111111111111111111111111100000000000000010000000000000000X00000000000000000000XX000000000000
Hylaeosaurus
???1??????????????????????????0000000000000??00??????????????????????11?0????????????11111??????00?????????0000???????
Pawpawsaurus
????1??11111111111??????????00?????????????????????1111111111111111???????????1111101?????000000??000000000???????????
Other nodosaurines
1111111211111111101111111111000000000000000000000001111111111111111111111111111111101111110000000000000000000000000000
Gargoyleosaurus
???????11111111112??????????00?????????????????????1111111111111111???????????00000???????111100??00000?100???????????
Shamosaurus
???????2111111111X??????????00?????????????????????111111111111111????????????00000??????01?????????????00????????????
Minmi
11111112111111111X111111111100000000000000000000000111111111111111111111111111000001000000111111110000??00?0000?000000
Gastonia
1??????2111111111X??????????00?????????????????????11111?1?1?1????????????????000001??????111111??11111?10???????????0
Pinacosaurus
1111111211111111111111111111000000000000000000000001111111111111111111111111110000000000001112111111111111111111111111
Other ankylosaurines
11111112111111111X1111111111000000000000000000000001111111111111111111111111111111?11111111112111111111111111111111111

3--Ornithopoda
This dataset includes 149 characters in 12 ornithopod taxa. Successively more remote outgroups include Marginocephalia and Thyreophora.

Characters and Character-States
Ornithopoda
1. Premaxilla-lacrimal contact: absent (0); present (1).
2. Paroccipital process, shape: subrectangular (0); crescentic (1).
3. Jaw articulation, position: approximately level with (0), or offset ventral to (1), the maxillary tooth row.
4. Premaxillary tooth row (or bill margin), position: level with (0), or ventral to (1), the maxillary tooth row.
Euornithopoda
5. Antorbital fenestra, maximum length: 75% or more of orbital diameter (0); approximately 50% of orbital diameter (1); very small or absent (2).
6. Quadrate foramen, location: posterolateral aspect of quadrate shaft (0); lateral aspect of quadrate or quadratojugal (1).
7. Quadrate foramen, size: foramen (0); fenestra (1).
8. External mandibular fenestra, length: more than 50% maximum depth of the lower jaw (0); small or absent (1).
9. Deltopectoral crest, form: projecting from shaft (0), or low or rounded (1) in lateral or medial view of the humerus.
10. Prepubic process, length: 15% or less (0), approximately 50% (1), or more than 100% (2) the length of the preacetabular process.
11. Ischial obturator process: absent (0); present (1).
Iguanodontia
12. Premaxilla, orientation of lower rim: ventrolateral (0); lateral (1).
13. Maxillary anteroventral process: absent (0); present (1).
14. Narial fossa, maximum length: shorter than (0), subequal to (1), or twice as long as (2) maximum anteroposterior diameter of the orbit.
15. Predentary bill margin, form: smooth (0); scalloped (1).
16. Dentary ramus, shape (lateral view): tapering anteriorly (0); rectangular (1); tapering posteriorly (to 70 % of maximum depth) (2).
17. Premaxillary teeth: present (0); absent (1).
18. Denticle shape: subconical (0); leaf-shaped (1).
19. Dentary crown, medial primary ridge: absent (0); present (1).
20. Manual digit III, phalangeal number: 4 (0); 3 (1).
21. Femoral anterior intercondylar groove: absent (0); V-shaped, broad (1); U-shaped, narrow (2).
22. Femoral posterior intercondylar groove: shallow (0); deep(1).
23. Tibial lateral malleolus, width: 60-70% (0), or 80-90% (1), of medial malleolus.
Dryomorpha
24. Quadrate, free portion of shaft: 10% or less (0), or 30% or more (1), of quadrate height.
25. Maxillary crowns, anteroposterior width: equal (0), or narrower (1), than dentary crowns.
26. Maxillary crowns, shape: subtriangular (0); diamond-shaped (1); lanceolate (2).
27. Maxillary primary ridge strength: less (0), or more (1), prominent than dentary primary ridge.
28. Ischial shaft, shape: dorsoventrally compressed (0); subcylindrical (1).
29. Ischial obturator process, position: just proximal to mid-shaft (0); between mid-shaft and pubic peduncle (1); near pubic peduncle (2).
30. Ischial foot: absent (0); present (1).
Ankylopollexia
31. Paroccipital process, width of base: equal to (0), or narrower than (1), broadest width of process.
32. Paroccipital process, shape of ventral tip: subtriangular (0); rod-shaped (1).
33. Inter-crown spaces: present (0); absent (1).
34. Denticules: absent (0); present (1).
35. Enamel, medial side of maxillary and lateral side of dentary crowns: present (partial or complete) (0), or absent (1), on medial side of maxillary crowns and lateral side of dentary crowns.
36. Postaxial cervicals, neural spine height: prominent (0); rudimentary (1).
37. Postaxial cervicals, form of postzygapophyses: weakly (0), or strongly (1), arched.
38. Cervicals 4-9, form of central surfaces: slightly amphicoelous (0); slightly opisthocoelous (1); strongly opisthocoelous (2).
39. Carpals and metacarpal I, articulation: free (0); coossified as two blocks (1).
40. Distal carpal 5-ulna, articulation: absent (0); present (1).
41. Manual digit I, orientation: 15-25ƒ (0), 45ƒ (1), or 60ƒ or more (2), from the axis of digit III.
42. Metacarpal I, length: more (0), or less (1), than 50% of metacarpal II length.
43. Manual digit I-phalanx 1, shape: longer than broad (0); broader than long (1); disc-shaped or absent (2).
44. Manual digit I-ungual, shape: claw-shaped (0); subconical (1).
45. Manual digit I-ungual, length: shorter (0); or longer (1), than manual digit II-ungual.
46. Pedal digit I, length: 50% or more (1), or 20% or less (2), of the length of pedal digit II.
Styracosterna
47. Postorbital bar, minimum width: approximately 25% (0), or 10% (1), of maximum orbital diameter.
48. Dentary coronoid process, shape: subtriangular (0); subrectangular (1); lobe-shaped distal expansion (50 % greater than minimum width at base) (2).
49. Postdentary bones, location: anterior (0), or posterior (1), to midline of coronoid process.
50. Maxillary and dentary teeth, number in tooth row: less (0), or more (1), than 20.
51. Axial spine, anterior extension of anterior process: anterior tip extending as far as (0), or considerably beyond (1), the prezygapophyses.
52. Axial spine shape (side view): subtriangular, bifurcation to postzygapophyses near posterior end of centrum (0); crecsentic, birfurcation to postzygapohpyses near mid centrum (1).
53. Sternal ventorolateral process: absent (0); present (1).
54. Metacarpals II-IV, configuration: spreading (0); appressed, ligament-bound (1).
55. Metacarpal IV, length: 60-70% of (0), or subequal to (1), metacarpal III.
56. Prepubic process, depth of distal end: subequal to (0), 25% greater than (1), or 50% greater than (2) the minimum depth of the process.
57. Iliac peduncle of pubis: absent (0); present (1).
58. Postpubic process, length: 100% (0), 50% (1), or less than 50% (2), of ischium.
59. Metatarsal II, minimum shaft width: subequal to (0), or 50-60% of (1), the minimum shaft width of metatarsal IV.
60. Pedal digits II-IV, ungual shape: claw-shaped (0); hoof-shaped (1).
Hadrosauriformes
61. Maxilla, articular flange for jugal: absent (0); present (1).
62. Quadratojugal, extent of jugal overlap: anterior edge (0); majority of lateral surface (1).
63. Squamosals, separation in midline: 100 % (0), 50% (1), or 0% (2) of the minimum width of the parietals between the supratemporal fossae (dorsal view).
64. Postpalatine foramen: present (0); absent (1).
65. Foramen magnum and occipital condyle, position: positioned posterior (0), or anterior (1) to the posterior margin of the skull roof.
66. Posttemporal foramen (on paroccipital process): present (0); absent (1).
67. Predentary posterolateral process, form: single (0); bifurcate (1).
68. Dentary tooth 1, position relative to the predentary: adjacent (0); separated by a short diastema (1); separated by a long diastema (2).
69. Dentary tooth row, posteriormost tooth: anterior (0), ventral (1), or posterior (2) to the coronoid process.
70. Surangular, contribution to quadrate cotylus: less (0), or more (1), than articular.
71. Cervical number: 9 (0); 11 (1); 12 (2); 13-15 (3).
72. Sacral number: 6 (0); 7 (1); 8 (2).
73. Metacarpal II length: subequal to (0), or 70-80% of (1), metacarpal III length.
74. Manual digits II-IV, phalanx 2 length: less (0), or more (1), than twice the length of phalanx 1.
75. Manual digit II-ungual, shape: broader (0), or narrower (1), than manual digit III-ungual.
76. Manual digit V, phalangeal number: 2 (0); 3 (1).
77. Manual digit V-phalanx 1, length: less than 50% (0), or subequal to (1), the length of metacarpal V.
78. Manual digits II and III, ungual shape: claw-shaped (0); hoof-shaped (1).
79. Iliac blade, dorsal margin: horizontal midsection (0); convex with apex of over pubic peduncle (1).
80. Iliac preacetabular process, length: subequal to (0), or longer than (1), the postacetabular process.
81. Iliac preacetabular process, depth of distal end: subequal to (0), or greater than (1), the proximal end of the process.
82. Pedal digit V: present (0); absent (1).
83. Ossified epaxial tendons, arrangement: intertwined (0); 2-layered lattice (1).
Hadrosauroidea
84. Premaxillary rim, shape of lateral margin: arcuate (0) lateral corner (1).
85. Premaxillary internarial bar, transverse width at midlength (dorsal view): approximately 50% of maximum width across the premaxillaries (0); approximately 20% of maximum width across the premaxillaries (1); thin septum of negligible width (2).
86. Jugal anterior end, shape: tapered (0); expanded dorsoventrally (1).
87. Postorbital skull roof, shape in dorsal view: parallel-sided (0); tapering in width posteriorly (1).
88. Paroccipital process, orientation: ventrally (0), or anteroventrally (1), directed.
89. Supraoccipital shape (posterior view): taller than broad (0); broader than tall (1).
90. Quadrate condyle, anteroposterior width of medial side: slightly narrower than (0), or approximately 50% of (1), the width of the lateral condyle.
91. Caudal neural spines, height: shorter (0), or longer (1), than respective chevrons.
92. Scapular blade, form of dorsal margin: straight (0); convex (1).
93.Iliac pubic peduncle, shape (lateral view): tapers to stout, subrectangular process (0); subtriangular (1).
94. Iliac dorsal antitrochanter: absent (0); present (1).
95. Iliac preacetabular process, length: less (0), or more (1), than 50% of ilium length.
96. Distal tarsals 3 and 4: present (0); absent (1).
97. Pedal digit I: present (0); absent (1).
Protohadros + Hadrosauridae
98. Antorbital fenestra/fossa: present (0); absent (1).
99. Maxilla, posterior pterygoid process: absent (0); present (1).
100. Jugal-quadrate contact, exclusion of quadratojugal from margin of laterotemporal fenestra: absent (0); present (1).
101. Predentary, posteromedian ridge on transverse ramus: absent (0); present (1).
102. Dentary teeth in vertical series: 2 (0); 3-6 (2).
Hadrosauridae
103. Skull shape (posterior view): subrectangular (0); trapezoidal (1).
104. Maxilla-lacrimal contact (anterior extension of jugal): present (0); very limited or absent (intervening jugal process extending anterior to orbit) (1).
105. Nasal anteriomedial process, length: extends to the midpoint (0), or the anterior end (1), of the internarial bar.
106. Jugal, anterior prong: absent (0); present (1).
107. Jugal-lacrimal articulation, form: overlapping (0); butt joint and groove (1).
108. Palpebrals: present (0); absent (completely fused or lost) (1).
109. Occipital condyle, shape of basioccipital portion: hemispherical (0); low, convex (1).
110. Jugal-ectopterygoid contact: present (0); absent (1).
111. Pterygoid, lamina between mandibular flange and quadrate process: absent (0); present (1).
112. Pterygoid quadrate flange, articulation of ventral portion: overlapping pterygoid wing of quadrate (0); butt joint against internal aspect of quadrate shaft (1).
113. Predentary transverse ramus and ventral process, orientation (lateral view): approximately 45ƒ (0), or 20ƒ (0), to the axis of the lateral processes.
114. Predentary triturating surface, orientation: dorsally (0), or dorsolaterally (1), facing.
115. Dentary coronoid process, lateral displacement from tooth row: near (0), or offset far lateral to (1), dentary tooth row.
116. Splenial shape: subtriangular (0); strap-shaped (1).
117. Splenial, position: middle (0), or posterior third (1), of lower jaw.
118. Angular, relative position on lower jaw: ventromedial (0); medial (1).
119. Surangular coronoid process, shape: subtriangular (broad adductor fossa) (0); prong-shaped (rim of adductor fossa only) (1).
120. Surangular foramen: present (0); absent (1).
121. Internal mandibular fenestra: present (0); absent (1).
122. Coronoid: present (0); absent (1).
123. Prearticular: present (0); absent (1).
124. Teeth, number of positions (maxilla/dentary): 25-28/25 (0), or 30-40/30-40 (1).
125. Dentary teeth, shape: diamond-shaped (0); lanceolate (1).
126. Maxillary and dentary teeth, secondary ridges: present (0); very reduced or absent (1).
127. Atlantal postzygapophyses, length: long, extend posterior to intercentrum (0); rudimentary (1).
128. Axial centrum, proportions (lateral view): longer than deep (0); subquadrate (1).
129. Cervicodorsal column, curvature (lateral view): broad (0); deep (1) sinuous curve.
130. Caudal vertebrae, number: approximately 45 (0); approximately 60 (1).
131. Ossified tendons, distribution: anterior dorsals through caudals (0); mid dorsals through caudals (1).
132. Scapula, maximum width of proximal end: greater (0), or subequal to or less (1), than maximum blade width.
133. Acromion, orientation: dorsolateral (0); lateral (1).
134. Coracoid, notch in anterior margin: absent (0); present (1).
135. Coracoid posterior process, location of distal tip: near (0), or far posterior (1), to the glenoid.
136. Humeral deltopectoral crest, length: 40-45% (0), or 55-60% (1), of humeral length.
137. Humeral distal condyles, width: approximately 200% (0), or 120-130% (1), of minimum shaft width.
138. Carpal form: block-shaped with intercarpal contact (0); small ovoids, suspended (1).
139. Metacarpus, maximum length: 20-30% (0), or 50% (1), of radial length.
140. Manual digit I: present (0); absent (1).
141. Metacarpals II-IV, distal condyles: present (0); absent (1).
142. Metacarpal V length: 40-50% (0), or 30-40% (1), of metacarpal II length.
143. Manual digits II, III, shape of penultimate phalanges: subrectangular (0); subtriangular (1).
144. Iliac dorsal antitrochanter, form: rounded eminence (0); prominent flange (1).
145. Iliac margin above antitrochanter, form: straight (0); notched (1).
146. Postpubic symphysis: present (0); absent (1).
147. Femoral fourth trochanter, form: pendant (0); subtriangular (1).
148. Astragalus, orientation of medial margin: 20ƒ or less (0), or 45ƒ or more (1), from a transverse axis (anterior margin).
149. Dentary anterior end, ventral deflection: moderate (0); strong (as far ventrally as depth of dentary ramus at midsection) (1).


Data Matrix
Outgroups
THYREOPHORA
00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000X00000
MARGINOCEPHALIA
00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000X00000
Ingroups
HETERODONTOSAURIDAE
11110000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000000000000000000000000000000000000000000000000000X00000
HYPSILOPHODONTOSAURIDAE
11111111111000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000X00000
Muttaburrasaurus
111111111111?1???1??111000X???000000000???????0000??????0??0000?00???0????????1000??000010?0000??0?0?000??000?????0??000???000?????00?00000?1??X0?00?
Tenontosaurus
11111111011111111111111000000000000001000000000000000000000000000000002000000000000000000000000000000000000000000000000000000000000000000000000X00000
DRYOSAURIDAE
11111111111111111111111111111100000001000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000X00000
CAMPTOSAURIDAE
11111111111111111111111111111111111112111111110000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000X00000
Probactrosaurus
11111111111111111111111111111111111112????????1111111??1???1??0???0?0?????????000??00?00??00000?????000?0???????000????????000??000000000?0?0??X0?000
IGUANODONTIDAE
11111111111112111111111111111111111112112121111111111111111111111111111111111111111000000000000000000000?0000000?0?0000000?00000000000000000000000000
Ouranosaurus
111111111111121211111111111121111111121111211X111111111211111111111101111111111111111111111111111000000?00000000?1?0000000?00000000000000000000000000
Protohadros
11111111???11212111????1121???11111???????????1111??????????0????????1?????????????111???1???????11111??000??0??000???00???000??????????????????????1
HADROSAURINAE
111111111111121111111111121121111111121XXX2XXX1211111112111101211111212211111111111121111111111111111111111111111111111111111111111111111111111111110
LAMBEOSAURINAE
111111111111121111111111121121111111121XXX2XXX1211111112111101211111213211111111111121111111111111111111111111111111111111111111111111111111111111111

4--Marginocephalia
This dataset, described in more detail elsewhere (4), includes 155 characters in 17 marginocephalian taxa. Successively more remote outgroups include Ornithopoda and Thyreophora.

Characters and Character-States
Marginocephalia
1. Parietosquamosal shelf: absent (0); present (1).
2. Premaxillary border of internal nares: present (0); absent (excluded by maxillae) (1).
3. Postpubic process length, distal symphysis: long, symphysis present (0); very short, symphysis absent (1).
Pachycephalosauria
4. Sacral rib length: subrectangular (0); strap-shaped (1).
5. Scapular blade, distal width: broad (0); narrow (1).
6. Preacetabular process, shape of distal end: tapered (0); expanded (1).
Goyocephale + more derived pachycephalosaurs
7. Frontal and parietal thickness: thin (0); thick (1).
8. Arched premaxilla-maxilla diastema, dentary canine: absent (0); present (1).
9. Postorbital and supratemporal bars, form: bar-shaped with smooth sutures (0); robust with interdigitating sutures (1).
10. Squamosal exposure on occiput: restricted (0); broad (1).
11. Anterior and posterior supraorbital bones: absent (0); present (1).
12. Postorbital-squamosal tubercle row: absent (0); present (1).
13. Postorbital-parietal contact: absent (0); present (1).
14. Squamosal, posterior tubercle row (5 to 7): absent (0); present (1).
15. Angular tubercle row: absent (0); present (1).
16. Basal tubera, shape: subcylindrical (0); plate-shaped (1).
17. Zygapophyseal articulations, form: flat (0); grooved (1).
18. Ossified interwoven tendons: absent (0); present (1).
19. Sternal shape: plate-shaped (0); shafted (1).
20. Humeral length: more (0), or less than (1), 50% of femoral length.
21. Humeral shaft form: straight (0); bowed (1).
22. Deltopectoral crest development: strong (0); rudimentary (1).
23. Iliac blade, lateral deflection of preacetabular process: weak (0); marked (1).
24. Iliac blade, medial tab: absent (0); present (1).
25. Fibular mid-shaft diameter: 1/4 or more (0), or 1/5 or less (1), mid-shaft diameter of tibia.
6. Preacetabular process, shape of distal end: tapered (0); expanded (1).
Homalocephale + Pachycephalosauridae
26. Parietal table, form: narrow and smooth (0); broad and rugose (1).
27. Quadratojugal free ventral margin, length: moderate (0); very short (1).
28. Pterygoquadrate rami, posterior projection of ventral margin: weak (0); pronounced (1).
29. Prootic-basisphenoid plate: absent (0); present (1).
30. Iliac blade, medial flange on postacetabular process: absent (0); present (1).
31. Ischial pubic peduncle, shape: transversely (0), or dorsoventrally (1), flattened.
32. Pubic body: substantial (0); reduced (1).
Pachycephalosauridae
33. Interfrontal and frontoparietal sutures: open (0); closed (1).
34. Frontoparietal doming: absent (0); partial (1); complete (posteriorly and laterally) (2).
35. Parietal-squamosal position relative to occiput: dorsal (0); posterodorsal (1).
36. Supratemporal opening: open (0); closed (1).
Pachycephalosaurinae
37. Jugal-quadrate contact: absent (0); present (1).
Tylocephale + Prenocephale
38. Quadratojugal fossa: absent (0); present (1).
Stygimoloch + Pachycephalosaurus
39. Preorbital skull length: much less than (0), or subequal to (1), length from anterior orbital margin to posterior aspect of quadrate head.
40. Squamosal node cluster: absent (0); present (1).
41. Anterior snout nodes: absent (0); present (1).
Ceratopsia
42. Rostral bone: absent (0); present (1).
43. Narial fossa, position: adjacent to (0), or separated by a flat margin from (1), the ventral margin of the premaxilla.
44. Jugal, lateral projection: chord from frontal orbital margin to extremity of jugal is less (0), or more (1), than minimum interorbital width.
45. Jugal (or jugal-epijugal) crest: absent (0); present (1).
46. Jugal infraorbital ramus, relative dorsoventral width: less (0), or subequal to or greater (1), than the width of the infratemporal ramus.
47. Premaxillary palate, form: flat (0); vaulted (1).
48. Predentary ventral process, width of base: less (0), or equal to or more (1), than half the maximum transverse width of the predentary.
Neoceratopsia
49. Premaxillary tooth number: 3 or more (0); 2 (1); 0 (2).
50. Premaxillary teeth, crown shape: recurved, transversely flattened (0); straight, subcylindrical (1).
51. Skull length (rostral-quadrate): 15% or less (0), or 20 to 30% (1), of length of postcranial skeleton.
52. Rostral lateral processes: rudimentary (0); well developed (1).
53. Snout anterior margin: rounded (0); keeled with point (1).
54. Predentary anterior margin: rounded (0); keeled with point (1).
55. Predentary posteroventral process, shape: broader distally (0); narrower distally (1).
56. Retroarticular process length: long (0); very short or absent (1).
Archaeoceratops + Leptoceratops + Coronosauria
57. Edentulous maxillary/dentary margin, length: 2 (0), or 4 or 5 (1), tooth spaces.
58. Maxillary teeth, primary ridge strength: low (0); prominent (1).
59. Maxillary/dentary primary ridge, position: near midline (0); offset posteriorly/anteriorly, respectively (1).
60. Maxillary/dentary teeth, packing: space between roots in adjacent teeth (0); no space between roots in adjacent tooth columns (1); no space between crowns within a tooth column (2).
61. Dentary tooth row, position of last tooth: anterior to (0), coincident with (1), or posterior to (2), the apex of the coronoid process.
62. Antorbital fossa shape: subtriangular (0); oval (1).
63. Postorbital and supratemporal bars, maximum width: narrow, bar-shaped (0); broad, strap-shaped (1); very broad, plate-shaped (2).
64. Infratemporal bar length: long, subequal to supratemporal bar (0); short, less than one-half supratemporal bar (1).
65. Jugal/epijugal crest: low (0); pronounced (1).
66. Quadrate shaft, anteroposterior width: broad (0); or narrow (1).
67. Predentary dorsal margin, form: sharp edge (0); bevelled cropping surface (1).
68. Dentary coronoid process, width and depth: narrow dentary process, low coronoid process (0); broad dentary process, moderately deep coronoid process (1); broad dentary process with distal expansion, very deep coronoid process (2).
Leptoceratops + Coronosauria
69. Maxillary/dentary crown, height: subequal to (0), or 1.5 times (1), maximum crown width.
70. Lateral maxillary/medial dentary crown base, form: convex (0), or inset (1), from root.
71. Jugal-squamosal contact above laterotemporal fenestra: absent (0); present (1).
72. Epijugal: absent (0); present (1).
73. Supratemporal fossae, relation: separated (0); joined in midline (1).
74. Posterior shelf composition: squamosal and parietal equal (0); squamosal dominant (1); parietal dominant (2).
75. Parietal shelf, inclination: horizontal (0); inclined posterodorsally (1).
76. Exoccipital-exoccipital contact below foramen magnum: absent (0); present (1).
77. Predentary surface between dentaries: absent (0); present (1).
78. Coronoid shape: strap-shaped (0); lobe-shaped (1).
79. Surangular eminence: absent (0); present (1).
80. Splenial symphysis: absent (0); present (1).
81. Axial neural spine, cross-section: V-shaped or subtriangular (0); blade-shaped (1).
82. Cervicals 1-3, vertebral articulations: free (0); fused (1).
83. Cervicals 3-4, neural spine height: much shorter than (0), or subequal to (1), the axial neural spine.
84. Posteriormost caudals, neural spines and chevrons: absent (0); present (1).
85. Mid and posterior caudals, neural spine cross-section: subrectangular (0); oval (1).
86. Tail shape: tapering (0); leaf-shaped (1).
Coronosauria
87. Enamel distribution, maxillary/dentary teeth: both sides of crown (0); restricted to lateral/medial sides in maxillary/dentary teeth (1).
88. Nasal horn: absent (0); present (1).
89. Supratemporal fenestra, shape: oval (0); subtriangular (1).
90. Supratemporal fenestra, orientation of long axis: parasagittal (0); posterolaterally divergent (1).
91. Parietal width: subequal to (0), or much wider than (1), the dorsal skull roof.
92. Parietal posterior extension: as far posteriorly as (0), just posterior to (1), or far posterior to (2), the quadrate head.
93. Paired parietal fenestrae: absent (0); present (1).
94. Hypocentrum: absent (0); present (1).
95. Sacral number: 5 or 6 (0); 8 (1 dorsal, 1 caudal added) (1).
96. Sacral neural spines, mutual contact: absent (0); present (1).
Ceratopsoidea
97. Dentary teeth, primary ridge strength: low (0); prominent (1).
98. Nasal horn position: posterior (0), or dorsal (1), to posterior margin of external nares.
99. Dentary ramus, position of maximum dorsoventral width: posterior (0); anterior (1).
100. Hypocentrum shape: wedge-shaped (0); U-shaped (1); ring-shaped (hemispherical occipital condyle) (2).
101. Mid cervical (C5-C7) neural spines, height: low (0); as high as dorsal neural spines (1).
Turanoceratops + Ceratopsidae
102. Maxillary/dentary teeth, root form: single (0); double (1).
103. Maxillary/dentary crowns, apical plane orientation: less (0), or more (1), than 45 degrees from the primary axis of the root.
104. Lateral maxillary/medial dentary crowns, secondary ridges: present (0); rudimentary or absent (1).
105. Postorbital horn: absent (0); present (1).
Ceratopsidae
106. Narial fossa, size: narrow margin (0), or broad area (1), anterior and ventral to external nares on the premaxilla.
107. Narial fossa, position of medial wall: parasagittal (0); median (1).
108. External naris, size: smaller than (0), or twice the size of (1), the orbit.
109. Antorbital fossa, size: 30% of maxilla (0); limited to a narrow margin (1).
110. Maxillary margin anterior to tooth row, orientation: anterodorsally inclined (0); horizontal (1).
111. Maxillary posterior alveolar process, length: less than 25% (0), or more than 30% (1), of maxillary tooth row length.
112. Jugal shape: subtriangular, extends under orbit (0); T-shaped, extends anterior to orbit (1).
113. Epijugal shape: crescentic (0); pyramidal (1).
114. Jugal-ectopterygoid contact: present (0); absent (1).
115. Squamosal-jugal contact below infratemporal fenestra: absent (0); present (1).
116. Squamosal frill process, orientation of lateral portion: vertical (0); oblique (1).
117. Frontal-parietal fontanelle: absent (0); present (1).
118. Pineal opening (in frontal-parietal fontanelle): absent (0); present (1).
119. Squamosal-paroccipital contact, orientation: dorsal (0); lateral (1).
120. Squamosal and parietal frill margin, form: smooth (0); scalloped (1).
121. Parietal medial rim over supratemporal fossa: absent (0); present (1).
122. Supraorbital, form of articulation with orbit: ligmentous (0); sutural (1); coossified (2).
123. Quadrate head, shape: rounded (0); plate-shaped (1).
124. Quadrate lateral process: present (0); absent (1).
125. Epoccipitals: absent (0); present (1).
126. Secondary palate, transversely broadest region: maxillary (0); premaxillary (1).
127. Posterior palate, ectopterygoid exposure: present (0); covered by palatine and pterygoid.
128. Pterygoid maxillary and quadrate rami, depth of separation: deep (0); shallow (1).
129. Supraoccipital border of the foramen magnum and participation in braincase wall: present (0); absent (1).
130. Paroccipital processes, parasagittal oval depressions: absent (0); present (1).
131. Supraocciptal lateral processes: present (0); absent (1).
132. Occipital condyle, basioccipital contribution: 50% (0); 30% (1).
133. Opening for CN I: single (0); divided (1).
134. Dorsal border of CN I: frontal (0); laterosphenoid (1).
135. Number of foramina for CN X-XII: 3 (0); 2 (1).
136. Quadrate head and jaw articulation, position: head posterior to orbit, jaw articulation level with tooth rows (0); head ventral to orbit, jaw articulation displaced below tooth rows (1).
137. Maxillary/dentary teeth, teeth in vertical series: two (0); four or five (1).
138. Maxillary/dentary teeth, number of tooth columns: 10-20 (0); 25 or more (1).
139. Body size: less (0), or more (1), than 1 ton.
140. Atlantal intercentrum length: shorter than (0), or subequal to (1), axial centrum.
141. C2 and C3 neural spines, orientation: erect (0); strongly posterodorsally inclined (1).
142. Cervical neural spines, shape: narrow (0); broad (1).
143. Sacrum shape (dorsal view): rectangular (0); oval (S4-6 ribs long, S1-3 and S7-9 shorter) (1).
144. Sacrum, median groove on the ventral surface: absent (0); present (1).
145. Glenoid composition: one-half (0), or two-thirds (1), of glenoid formed by scapula.
146. Scapular spine: absent (0); present (1).
(from glenoid lip to middle of scapular blade)
147. Ossified clavicles: present (0); absent (1).
148. Iliac blade, orientation: vertical (0); horizontal (1).
149. Iliac pre- and postacetabular processes, maximum width: preacetabular process narrower (0), or broader (1), than postacetabular process.
150. Iliac antitrochanter: absent (0); present (1).
151. Prepubic process, length: shorter than (0), or subequal to (1), iliac preacetabular process.
152. Prepubic process, shape of distal end: tapered (0); flared (1).
153. Pubic acetabular process: absent (0); present (1).
154. Femoral fourth trochanter, shape: pendant (0); crescentic (1).
155. Tibia-astragalus contact, form: free (0); coossified (1).<9>

Data Matrix
Outgroups
THYREOPHORA
0000000000000000000000000000000000000000?0000000000X00?000000000X000000000X0000000000000000000000X0X000000000000X00X000X00000X00000000000000000000100000000
ORNITHOPODA
000000000000000000000000000000000000000000000000000X000000000000X000000000X0000000000000000000000X0X000000000000X00X000X00000X00000000000000000000100000000
Ingroups
Stenopelix
??1111???????????0?00?000????000???????????????????????????????????????????????????000????????0???????????????????????????????????????????0???0????00000000
Goyocephale
11???1111111111111111111?0??11??0000??00?0000000000X0??0000?0X0?X??000000100?000?0?00000000?0?0?0X0??00000000000X?0X000X010000??00?0???00000??00???000????0
Homalocephale
1?11?11?111111??111???1111111111000000000??000????0??????00??X00X0??00000100???????0000?000?0?00?????0000???0?00X00X000X01000?000000??00000???0????00000000
Stegoceras
11??11111111111111111111111111111111000000000000000X0??0000??X00X0?000000100?000????0?00000?0?0?0X0??00000000100X00X000X0100000000000000000????000?000???10
Tylocephale
1?????1?1111111??????????11?????121111000??000??????????0???0?00X1??00000100????????????XX0?0????????0000?????00X?0X000X01000??????0???0000????????????????
Prenocephale
11?1?111111111?1?1????11?1X11111121111000000000?000X0???000??X00X0??00000100??????????00XX0?0?0??X???00000000000X00X000X010000000000??00000???0????000???0?
Stygimoloch
1?????1?111?11???????????1??????1211??111???????????????????????????????010?????????????XX0?0???????????0?????????????????????????0?00????1????????????????
Pachycephalosaurus
1?????1?111111???????????1X11???121110111??000???????????000?X00X0??00000100??????????00XX0?0????X???0000000??00X?0X000X010?0?0?0000???0001????????????????
Psittacosaurus
1110000000000000000000000000000000000000011111112X00000000000X00000000000000000000000000000000000X0X00000000X000X00X000X00000000000000000000000000000000000
Chaoyangsaurus
????0?????????0??????0????0?????????000??11111?11111111100000??00??000?00??0??00000???0????0????0?0?0000?0000000X??????????????????0???0000?00??00?????????
Archaeoceratops
1?10?0000000000?00????00??00?0?000000000011111??11111111111111111111??0????????0???000?00001??000X0??00000000?000?0X000000?00??????0???0000??000???000000?0
Leptoceratops
1110000000000000000000000000000000000000011111112X11111111111111111111111211111111111100000100000000000000000000000X00000000000000000?000000000000000000000
PROTOCERATOPSIDAE
1110000000000000000000000000000000000000011111111110111111111111111111111211111111111111111211110000000000000000000000000000000000000?000000000000000000000
Montanoceratops
1?1000000000?00000000000000?0000000000000??11??1??1???1??11?11210??111?1?211?11111111111??021111111110000???00?00?000??000000????0?0??000000000000000000000
Turanoceratops
?????????????0??????????0??????????????????????1?????11?111???????1?11?1????1???????????????????1????1111????0??????????????????????????000????????????????
CENTROSAURINAE
1110000000000000000000000000000000000010010101112X11111111122X210112111112111110111100111112111111121111111111111111111112111111111111111111111111111111111
CERATOPSINAE
1110000000000000000000000000000000000010010101112X11111111122X210112111112111110111100111112111111121111111111111111111112111111111111111111111111111111111

5--Prosauropoda
This dataset includes 32 characters in 9 prosauropod genera. Successively more remote outgroups include Sauropoda and Theropoda.

Characters and Character-States
Prosauropoda
1. Premaxillary beak: absent (0); present (1).
2. Premaxilla-maxilla external suture: oblique (0); L-shaped (1).
3. Secondary antorbital fossa wall: absent (0); present (1).
4. Maxillary vascular foramina, form: irregular (0); 1 directed posterior, 5-6 anterior (1).
5. Squamosal ventral process, shape: tab-shaped (0); strap-shaped (1).
6. Dentary tooth 1, position: terminal (0); inset (1).
7. Axial postzygapophyses, length: overhang (0), or flush with (1), the posterior centrum face.
8. Deltopectoral crest, length: less (0), or equal to or more (1), than 50% of the length of the humerus (1).
9. Deltopectoral crest, deflection: 45ƒ-60ƒ (0), or 90ƒ (1), to the transverse axis of the distal condyles.
10. Distal carpal 1, size: small (0); large (1).
11. Metacarpal I, basal articulation: flush with other metacarpals (0); inset into the carpus (1).
12. Metacarpal I, basal width: less than 50% (0), or more than 65% (1), maximum length.
13. Manual digit I, phalanx 1, proximal heel: absent (0); present (1).
14. Manual digit I-phalanx 1, rotation of axis through distal condyles: rotated slightly ventromedially (0); rotated 45ƒ ventrolaterally (1); rotated 60ƒ ventrolaterally (2).
15. Iliac preacetabular process, shape: blade-shaped (0); subtriangular (1).
16. Iliac preacetabular process, scar: absent (0); present (1).
17. Ischial distal shaft cross-section: ovate (0); subtriangular (1).
18. Metatarsal II proximal articular surface: subtriangular or subquadrate (0); hourglass-shaped (1).
19. Metatarsal IV proximal end, transverse width: subequal (0), 3 times broader than (1), dorsoventral depth.
Plateosauria
20. Premaxillary posterodorsal process, shape of distal end: tapered (0); transversely expanded (1).
21. Nasal anteroventral process, basal width: subequal to (0), or 50% broader than (1), anterior process.
22. Median nasal depression: absent (0); present (1).
23. Prefrontal posterior process, size: small (0); large (1).
24. Cervicals 2-8 centra, length: less than (0); more three times diameter (1).
Plateosauridae
25. Frontal exposure between nasal and prefrontal: absent (0); present (1).
26. Jaw articulation, position: just below (0), or approximately 25% of the length of the tooth row below (1), the tooth row.
Coloradisaurus + Sellosaurus + Plateosaurus
27. Dentary anterior end, orientation: straight (0); ventrally curved (1).
28. Basal tubera/basiptrygoid processes, position: near (0), or offset below (1), the level of the occipital condyle.
29. Deep transverse septum between basipterygoid processes: absent (0); present (1).
Sellosaurus + Plateosaurus
30. Nasal participation in secondary antorbital fossa wall: absent (0); present (1).
31. Premaxillary tooth number: 4 (0); 5 (1); 0 (2).
Massospondylidae
32. Snout, maximum width: subequal (0), or 30% greater (1), than maximum snout height.

Data Matrix
Outgroups
THEROPODA
00000000000000000000000000000000
SAUROPODA
00000000000000000000000000000000
Ingroups
Riojasaurus
1111111111111111111???0000000000
"Griposaurus" sinensis
??????1111111111111????0????????
Ammosaurus (= Anchisaurus)
?111111111111210111????100000000
Yunnanosaurus
?11111111?1112111111??11?00??001
Massospondylus
111111?11111121111111111?0000001
Lufengosaurus
?1111111111112111111111111000000
Coloradisaurus
?11111?????????????11??1?1111000
Sellosaurus
?11111111111121111111??111111110
Plateosaurus
11111111111112111111111111111110

6--Sauropoda
116 characters are considered in 11 sauropod taxa, with Prosauropoda and Theropoda serving as successively more remote outgroups. This dataset differs only slightly from that in a recent analysis of basal sauropod phylogeny (5). Two major subclades (Dicraeosauridae, Diplodocidae) of one terminal taxon (Diplodocoidea) are scored separately and seven characters (86-92) have been added supporting diplodocoid monophyly (5).

Characters and Character-States
Sauropoda
1. Posture: bipedal (0); columnar, obligatory quadrupedal posture (1).
2. Sacral vertebrae, number: 3 or fewer (0); 4 (1); 5 (2); 6 (3). (2)
3. Humerus, deltopectoral attachment, development: prominent (0); reduced to a low crest or ridge (1).
4. Ulna, olecranon process: prominent, projecting above proximal articulation (0); rudimentary, level with proximal articulation (1).
5. Ulna, proximal condyle, shape: subtriangular (0); triradiate, with deep radial fossa (1).
6. Radius, distal condyle, shape: round (0); subrectangular, flattened posteriorly and articulating in front of ulna (1).
7. Ilium, ischial peduncle, size: large, prominent (0); low, rounded (1).
8. Ischial blade, length: much shorter than (0); equal to or longer than pubic blade (1).
9. Ischial distal shaft, shape: triangular, depth of ischial shaft increases medially (0); bladelike, medial and lateral depths subequal (1).
10. Femur, cross-section, shape: round (0); elliptical, with long axis oriented mediolaterally (1).
11. Femur, fourth trochanter, development: prominent (0); reduced to crest or ridge (1).
12. Astragalus, foramina at base of ascending process: present (0); absent (1).
13. Distal tarsals 3 and 4: present (0); unossified (1).
14. Metatarsal I and V proximal condyle, size: smaller than (0); subequal to metatarsal II and IV (1).
15. Metatarsal V, length: shorter than (0); at least 70% length of metatarsal IV (1).
16. Pedal digit I ungual, length relative to pedal digit II ungual: subequal (0); 25% larger than that of digit II (1).
17. Pedal ungual I, shape: broader transversely than dorsoventrally (0); sickle-shaped, much deeper dorsoventrally than broad transversely (1).
Eusauropoda
18. External nares, position: terminal (0); retracted to a level with orbit (1); retracted above orbit (2).
19. Premaxilla, anterior margin, shape: without step (0); with marked step, anterior portion of skull sharply demarcated (1).
20. Antorbital fossa: present (0); absent (1).
21. Maxillary border of external naris, length: short (0); long (1).
22. Prefrontal, anterior process: present (0); absent (1).
23. Squamosal-quadratojugal contact: present (0); absent (1).
24. Quadratojugal, anterior process, length: short, anterior process shorter than dorsal process (0); long, anterior process approximately twice as long as the dorsal process (1).
25. Orbit, ventral margin, anteroposterior width: broad, subcircular orbital margin, laterotemporal fenestra posterior to orbit (0); reduced, acute orbital margin, laterotemporal fenestra extends under orbit (1).
26. Supratemporal region, anteroposterior width: temporal bar longer anteroposteriorly than transversely (0); temporal bar shorter anteroposteriorly than transversely (1).
27. Supratemporal fossa, lateral exposure: not visible laterally, obscured by temporal bar (0); visible laterally, temporal bar shifted ventrally (1).
28. Quadrate, posterior fossa: absent (0); present (1).
29. Palatine, lateral ramus, shape: plate-shaped (long maxillary contact) (0); rod-shaped (narrow maxillary contact) (1).
30. Dentary, anterior end of ramus, depth: slightly less than that of dentary at midlength (0); 150% minimum depth (1).
31. Tooth rows, shape of anterior portions: narrowly arched, anterior portion of tooth rows V-shaped (0); broadly arched, anterior portion of tooth rows U-shaped (1).
32. Tooth crowns, cross-sectional shape at mid-crown: elliptical (0); D-shaped (1); cylindrical (2).
33. Enamel surface texture: smooth (0); wrinkled (1).
34. Tooth crowns, orientation: aligned along jaw axis, crowns do not overlap (0); aligned slightly anterolingually, tooth crowns overlapping (1).
35. Crown-to-crown occlusion: absent (0); present (1).
36. Occlusal pattern: V-shaped facets (interlocking) (0); high-angled planar facets (1); low-angled planar facets (2).
37. Cervical vertebrae, number: 9 or fewer (0); 10 (1); 12 (2); 13 (3); 15 or greater (4).
38. Cervical centra, articular face shape: amphicoelous (0); opisthocoelous (1). (38)
39. Mid-cervical neural spines, height: less than that of posterior centrum face (0); greater than height of posterior centrum face (1).
40. Dorsal neural spines, breadth: narrower transversely than anteroposteriorly (0); much broader transversely than anteroposteriorly (1).
41. Chevrons, shape: Y-shaped (0); "forked" with anterior and posterior projections (1).
42. Carpal bones, shape: round (0); block-shaped, with flattened proximal and distal surfaces (1).
43. Manual digits II and III, phalangeal number: 2-3-4-3-2 or more (0); reduced, 2-2-2-2-2 or less (1).
44. Manual phalanges (other than unguals), shape: longer proximodistally than broad transversely (0); broader transversely than long proximodistally (1).
45. Iliac blade, dorsal margin, shape: flat (0); semicircular (1).
46. Pubic apron, shape: flat (0); canted anteromedially, with gentle S-shaped medial margin (1).
47. Tibia, cnemial crest, orientation: projecting anteriorly (0); laterally (1).
48. Tibia, distal posteroventral process, size: broad transversely, covering posterior fossa of astragalus (0); reduced, posterior fossa of astragalus visible posteriorly (1).
49. Fibula, lateral trochanter: absent (0); present (1).
50. Metatarsal III length: 30% or more (0), or 25% or less (1), that of tibia.
51. Metatarsal I, minimum shaft width: less than (0) or greater than (1) that of metatarsals II-IV.
52. Metatarsus, posture: bound (0); spreading (1).
53. Pedal phalanges (other than unguals), shape: longer proximodistally than broad transversely (0); broader transversely than long proximodistally (1).
54. Pedal digit I ungual, length relative to metatarsal I: shorter than metatarsal I (0); longer than metatarsal I (1).
55. Pedal digits II-IV, penultimate phalanges, development: subequal in size to more proximal phalanges (0); rudimentary or absent (1).
56. Pedal ungual II-III, shape: broader transversely than dorsoventrally (0); sickle-shaped, much deeper dorsoventrally than broad transversely (1).
57. Pedal digit IV ungual, development: subequal in size to unguals of pedal digits II and III (0); rudimentary or absent (1).
Barapasaurus + Omeisaurus + Neosauropoda
58. Posterior cervical and anterior dorsal neural arches, intraprezygapophyseal lamina: absent (0), present (1).
59. Anterior dorsal centra, articular face shape: amphicoelous (0); opisthocoelous (1).
60. Middle and posterior dorsal neural spines, lateral lamina formed by the union of spinodiapophyseal and suprapostzygapophyseal laminae: absent (0); present (1).
61. Sacrum, sacricostal yoke: absent (0); present (1).
62. Fibula, proximal tibial scar, shape: not well-marked (0); well-marked and deepening anteriorly (1).
63. Astragalus, posterior fossa, shape: undivided (0); divided by vertical crest (1).
64. Pedal unguals, orientation: aligned with (0), or deflected lateral to (1), digit axis.
Omeisaurus + Neosauropoda
65. Frontal contribution to supratemporal fossa: present (0); absent (1).
66. Supratemporal fenestra, long axis orientation: anteroposterior (0); transverse (1).
67. Dentary teeth, number: greater than 20 (0); 17 or fewer (1).
68. Presacral pleurocoels, shape: shallow lateral depressions (0); deep lateral excavations bordered by a sharp lip (1).
69. Cervical pleurocoels, shape: simple, undivided (0); complex, divided by bony septa (1).
70. Dorsal vertebrae, number: 15 (0); 14 (1); 13 (2); 12 or fewer (3).
71. Cervical rib, tuberculum-capitulum angle: greater than 90ƒ (0); less than 90ƒ, rib ventrolateral to centrum (1).
72. Scapula, acromion process, size: narrow (0); width more than 150% minimum width of blade.
73. Metatarsals III and IV, minimum transverse shaft diameters: subequal to (0) or less than 65% (1) that of metatarsals I or II (1).
Neosauropoda
74. Preantorbital fenestra: absent (0); present (1).
75. Postorbital, ventral process, shape: transversely narrow (0); broader transversely than anteroposteriorly (1).
76. Jugal-ectopterygoid contact: present (0); absent (1).
77. External mandibular fenestra: present (0); absent (1).
78. Marginal tooth denticles: present (0); absent (1).
79. Carpal bones, number: 3 or more (0); 2 or fewer (1).
80. Metacarpus, shape: spreading (0); bound, with subparallel shafts, and articular surfaces extending half their length (1).
81. Metacarpals, shape of proximal surface: gently curving, forming a 90ƒ arc (0); U-shaped, subtending a 270ƒ arc (1).
82. Pelvis, anterior width: narrow, ilia longer anteroposteriorly than distance separating preacetabular processes (0); broad, distance between preacetabular processes exceeds anteroposterior length of ilia (1).
83. Tibia, proximal condyle, shape: narrow, long axis anteroposterior (0); expanded transversely, condyle subcircular (1).
84. Astragalus, ascending process, length: limited to anterior two-thirds of astragalus (0); extending to posterior margin of astragalus (1).
85. Astragalus, shape: rectangular (0); with reduced anteromedial corner (1).
Diplodocoidea
86. Dentary, form of anteroventral corner: rounded right angle (0); ventrally projecting "chin" (1).
87. Basipterygoid processes, length: stout, twice diameter (0); subcylindrical, at least 4 times diameter (1).
88. Cervical ribs, length: longer (0), or shorter (1), than respective centra.
89. Dorsal and anterior caudal vertebrae, neural arch height: less (0), or more (1), than 2.5 times height of anterior centrum.
90. Posterior caudal vertebrae, form: gradual decrease in size, centrum length 2-3 times height (0); 20 or more subcylindrical, biconvex centra.
91. Calcaneum: present (0); absent (or unossified) (1).
92. Metatarsal I lateral distal condyle, form: symmetrical (0); flared laterally (1).
Macronaria
93. Middle and posterior dorsal neural spines, shape: tapering or not flaring distally (0); flared distally, with triangular lateral processes (1).
94. Chevrons, proximal "crus" bridging superior margin of haemal canal: present (0); absent (1).
95. Ischial distal shafts, cross-sectional shape: V-shaped, forming an angle of nearly 50ƒ with each other (0); flat, nearly coplanar (1).
Camarasaurus + Titanosauriformes
96. External naris, maximum diameter: shorter (0), or longer (1) than orbital maximum diameter.
97. Quadrate, posterior fossa, depth: shallow (0); deep (1).
98. Surangular, depth: less than twice (0); or more than two and one-half times (1) maximum depth of the angular.
99. Posterior dorsal centra, articular face shape: amphicoelous (0); opisthocoelous (1).
100. Highest metacarpal-to-radius ratio: close to 0.3 (0); 0.45 or more (1).
101. Metacarpal I, length: shorter than metacarpal IV (0); longer than metacarpal IV (1).
102. Puboischial contact, length: approximately one-third (0); or one-half (1) total length of pubis.
Titanosauriformes
103. Pterygoid, dorsomedially oriented basipterygoid hook: present (0); absent (1).
104. Dorsal ribs, proximal pneumatocoels: absent (0); present (1).
105. Metacarpal I, distal condyle shape: divided and asymmetrical (0); undivided and flat with respect to axis of shaft (1).
106. Ilium, preacetabular process, shape: pointed, arching ventrally; semicircular, oriented anterodorsally (1).
107. Femoral shaft, lateral margin shape: straight (0); proximal one-third deflected medially (1).
Somphospondyli
108. Cervical vertebrae, neural arch lamination: well-developed, with well- defined laminae and coels (0); rudimentary; diapophyseal laminae only feebly developed if present (1).
109. Presacral vertebrae, bone texture: solid (0); spongy, with large, open internal cells (1).
110. Anterior and mid-cervical neural spines, orientation: nearly vertical with respect to the vertebral axis (0); posterodorsally inclined, approximately 45ƒ from vertical in lateral view (1).
111. Scapular glenoid, orientation: relatively flat (0); strongly beveled medially (1).
Particularly homoplastic characters
112. Posterolateral processes of premaxilla and lateral processes of maxilla, shape: without midline contact (0); with midline contact forming marked narial depression, subnarial foramen not visible laterally (1).
113. Posterior cervical and anterior dorsal neural spines, shape: single (0); bifid (1).
114. Cervical centra, anteroposterior length/height of posterior face: 2.5-3.0 (0); >4 (1).
115. Distalmost caudal centra, articular face shape: platycoelous (0); biconvex (1).
116. Scapula, distal blade, shape: acromial edge not expanded (0); with rounded expansion on acromial side (1).

Data Matrix
Outgroups
THEROPODA
00000000000000000000000000000000000X00000000000000000000000000000000X00X00000X000000000000000000X0001000000100000000
PROSAUROPODA
00000000000000000000000000000000000X10000000000000000000000000000000X100000000000000000000000000X0000000000100000000
Ingroups
Vulcanodon
11111111111111111????????????????????????????00?000000000???0000????????0?????????000??????0?00????0?0????0????????0
Shunosaurus
11111111?1111111111111111111111111113111111111111111111110000??0000002000?00010000?000000000010000000000000100000000
Barapasaurus
1111111111111???1??????????????1?????1111???11111????????1111111???00????????0???00?????0???000???0??0???000000?0000
Omeisaurus
12111111?1111111111111111111?1111111410111111111?111111111111111111113111???00000000000000000000000000?0000000000100
DICRAEOSAURIDAE
121111111111111112011111111111121012211111111111111111111111111111111311111111111111111111110000000000?0000000001000
DIPLODOCIDAE
121111111111111112011111111111121012411111111111111111111111111111111311111111111111111111110000000000?0000000001010
Haplocanthosaurus
12????11111?????????????????????????3111????11???????????1111??????11210?????????1?????000??111???0??0?0?000000?00?0
Camarasaurus
12111111111111111111110111111111111121111111111111111111111111111111131111111111111110000000111111111100000000011001
BRACHIOSAURIDAE
1201111111111111111111111111101110113111?1111111111111111111111111111?11111111111111100000?01111111111111110000101?1
Euhelopus
131???1111111??111111?11???1111111114111????1111111111?1?111???1??111211101?11???11?100000101?1?011????1?111111010?0
TITANOSAURIA
13101110111111111111?11111111111101331110?1X1111111111111111111111111310111?1111111110000010111?11111111111111110011

7--Ceratosauria
This dataset includes 60 characters in 11 ceratosurian taxa, with Tetanurae and Herrerasauridae serving as successively more remote outgroups.

Characters and Character-States
Ceratosauria
1. Postaxial cervical and dorsal vertebrae, posterior pleurocoel: absent (0); present (1).
2. Pelvic girdle sutures: open (0); fused (1).
3. Supraacetabular crest, size: shelflike (0); pendant (1).
4. Brevis fossa, posterior end: narrow (0); broad (1).
5. Iliac postacetabular process, posterior margin: convex (0); concave (1).
6. Ischial antitrochanter, anterior margin: straight (0); notched (1).
7. Ischial antitrochanter, size: less (0), or subequal or greater (1), than adjacent articular surface for ilium.
8. Ischial foot: absent (0); present (1).
9. Pubic fenestra: absent (0); present (1).
10. Femoral anterior trochanter, dimorphism: absent (0); present (1).
11. Femoral trochanteric shelf, development: rugosity or low ridge (0); trough-shaped (1).
12. Femoral fibular condyle, separation: weak (0); marked (1).
13. Astragalus-calcaneum, suture and mutual processes: open, present (0); fused, absent (1).
Ceratosauroidea
14. Premaxilla shape: longer than deep (0), or deeper than long (1), under the external naris.
15. Sacral number: 3 (0); 5 (1); 6 (2).
16. Mid sacral centra, ventral margin: horizontal (0); dorsally arched (1).
17. Humeral shaft axis: sigmoid (0); straight (1).
Abelisauridae
18. Tooth row, transverse curvature: minor (0); marked (1).
19. Skull, external sculpturing: absent (0); present (1).
20. Antorbital fossa width: broad (0); narrow (1).
21. Nasal-nasal suture: open (0); fused (1).
22. Lacrimal-postorbital contact: absent (0); present (1).
23. Frontal-parietal suture: open (0); fused (1).
24. Parietal sagittal crest: absent (0); present (short) (1).
25. Nuchal wedge and parietal alae, size: small (0); hypertrophied, elevated well above rest of skull roof (1).
Carnotaurinae
26. Pre-orbital skull length: more (0), or less (1),than 50 % of skull length.
27. Maxilla-jugal contact, length: short (0); long, broad (1).
28. Postorbital ventral process, form near ventral end: rounded (0); inset (1)
29. External mandibular fenestra, size/position: anterior end posterior (0), or ventral (1), to last dentary tooth.
30. Dentary posteroventtral process, length: long (0); short, extending only as far posteriorly as the posterodorsal process.
31. Cervical epipophyses, anterior process: absent (0); present (1).
32. Mid sacral centra, transverse dimensions: similar to adjacent sacrals (0); strongly constricted (1).
Coelophysoidea
33. Skull length: less (0), or more (1), than 3 times posterior skull height.
34. Premaxilla-maxilla arched diastema: absent (0); present (1).
35. Alveolar premaxilla-maxilla suture: present (0); absent (1).
36. Premaxillary tooth row, position of posterior end: ventral (0), or anterior (1), to external naris.
37. Dentary anterior end, form: rounded (0); expanded dorsoventrally (1).
38. Dentary tooth 3, size: subequal (0), or enlarged (1), relative to tooth 2.
39. Axis, anterior pleurocoel: present (0); absent (1).
40. Distal caudal prezygapophyses, length: 40% (0), or 30% or less (1), overlap of preceding centrum.
41. Pubic foot, anteroposterior length: longer (0), or shorter (1), than ischial foot.
42. Distal tibial flange posterior to fibula, shape: lobe-shaped (0); tabular (1).
Liliensternus + Coelophysidae
43. Antorbital fossa, anterior end: posterior (0), or ventral (1), to posterior end of external naris.
44. Antorbital fossa ventral margin, rounded rim: absent (0); present (1).
45. Mid-cervical (C3-C6) centrum length: less than 3 (0), 3 (1), or more than 4 (2), times centrum height.
46. Ischium length: subequal to (0), or shorter than (1), pubis length.
47. Ischial mid-shaft, cross-sectional shape (paired): oval (0); heart-shaped (1); subrectangular (2).
Coelophysidae
48. Dorsal centrum length: subequal to (0), or more than 2.5 times (1), centrum height.
49. Distal tarsal 3 and metatarsals II and III, sutures: open (0); fused (1).
50. Pubic shaft, axis: straight (0); bowed anteriorly (1).
Procompsognathinae
51. Pubic shaft, rodlike lateral portion: robust (0); reduced (1).
52. Pubic foot: present (0); absent (1).
Coelophysinae
53. Promaxillary fenestra: present (0); absent (1).
54. Supratemporal fossa, postorbital participation: present (0); absent (1).
55. Basisphenoid fontanelle: present (0); absent (1).
56. Posterior cervical and dorsal vertebrae, transverse process shape: subrectangular (0); subtriangular (1).
57. Sacrum shape, dorsal view: subrectangular (0); subtriangular (1).
58. Sacral transverse processes: separate (0); joined (1).
59. Distal caudal centrum length: three-to-four (0), or seven (1), times centrum height.
60. Postacetabular process, lateral attachment scar: subtle (0); pronounced (1).

Data Matrix
Outgroups
HERRERASAURIDAE
000000000000000000000000000000000000000000000000000000000000
TETANURAE
000000000000001000000000000000000000000000000000000000000000
Ingroups
Elaphrosaurus
111111111?111?211?????????????00???????000??1??0000????00000
Ceratosaurus
1111?1111111112110000000000000010000000000000000000000000000
Abelisaurus
?????????????1???111111110?0????0000??????00????????00??????
Majungatholus
??1??????????1???11111111111111?000000????0000??????0000????
Carnotaurus
111111111?11112111111111111111110000000000000000?000000000?0
Dilophosaurus
1?1111111111101000000000000000001111111111001000000000000000
Liliensternus
101111111?011?1000??0???????0000?1??11111111211000000??0?000
Procompsognathus
111???????1?1????????0????????0?????????X?????211111???0????
Segisaurus
?11????01?1?????1???????????????????????X????12??111????????
Syntarsus
111111111111101010000100000000001111111111112111110011111111
Coelophysis

8--Tetanurae
This dataset includes 204 characters in 17 tetanuran taxa, with Ceratosauria and Herrerasauridae serving as successively more remote outgroups. Analysis (under maximum parsimony) results in six trees (CI, 0.67; RI, 0.81).

Characters and Character-States
Tetanurae
1. Lacrimal, antorbital pneumatic recess: absent (0); present (1).
2. Lacrimal-jugal articulation, form: overlapping (0); slotted (1).
3. Maxillary tooth row, posteriormost tooth position: ventral (0), or anterior (1), to the orbit.
4. Axial neural spine width: tapers (0), or expands (1), distally.
5. Chevron base, paired anterior and posterior processes: absent (0); present (1).
6. Metacarpal III, mid-shaft transverse diameter, and III-ungual length: subequal to digit II (0); diameter 55% or less metacarpal II, ungual length less than 70% II-ungual (1).
7. Iliac-ischial articulation, anteroposterior width: subequal to (0), or much smaller than (1), iliac-pubic articulation (1).
8. Ischial obturator notch (or foramen): absent (0); present (1).
9. Femoral anterior trochanter, form: sigmoid (0); blade-shaped (1).
10. Tibial distal end, extension of posterolateral flange: partially (0), or completely (1), backs the distal end of fibula and calcaneum.
11. Fibular distal end, maximum width: more (0), or less (1), than twice minimum anteroposterior width of fibular shaft.
12. Astragalar ascending process, thickness: wedge-shaped (0); 3-4 times taller than thick anteroposteriorly at midpoint (1); plate-shaped, more than 5 times taller than thick at midpoint (2).
13. Astragalar articular surface for distal end of fibula, size: 75% or more (0), or approximately 30 % (1), of distal articular cup for fibula.
14. Astragalar distal articular surface, orientation: ventrally directed (0); ventrally and anteriorly directed (1).
15. Metatarsal III, shape and area of proximal articular surface: subrectangular, with minimum transverse width subequal to, or greater than, either metatarsals II or IV (0); hourglass-shaped, with minimum transverse width less than either metatarsals II or IV (1); subrectangular, with maximum transverse width less than either metatarsals II or IV (2); vestigal, with metatarsals II and IV contacting anteriorly (3).
16. Metatarsal III, mid-shaft shape: subrectangular (0); wedge-shaped (anterior overlap on metatarsals II and IV).
Neotetanurae
17. Maxillary fenestra: absent (0); present (1).
18. Promaxillary recess, degree of anterior invagination: medial to rim of antorbital fossa (0); extending into anterior ramus of maxilla (1).
19. Jugal, antorbital pneumatic excavation: absent (0); present (1).
20. Prefrontal-frontal articulation: planar or grooved (0); peg-in-socket (1).
21. Jugal, antorbital pneumatic excavations: absent (0); present (1).
22. Ectopterygoid pneumatic excavation, form: depression (0); invaginated on lateral side (1).
23. Splenial border of internal mandibular fenestra, shape: concave (0); notched (1).
24. Articular, orientation of retroarticular face: dorsal (0); posterior (1).
25. Anterior dorsal vertebrae, pendant hypapophyses: absent (0); present (1).
26. Posterior chevrons, blade shape (lateral view): gently curved (0); L-shaped (1).
27. Furcula (clavicular fusion): absent (0); present (1).
28. Coracoid posterior process and fossa, shape: subtriangular with subcircular fossa (0); crescentic with crescentic fossa (1).
29. Distal carpal(s), form of proximal articular surface: subplanar (0); transverse trochlea (1).
30. Manual digit IV: present (0); absent (1).
31. Iliac preacetabular process, form of anterior margin (lateral view): smoothly convex (0); notched (1).
32. Iliac preacetabular fossa: absent (0); present (1).
33. Iliac pubic peduncle, shape of distal articular surface: subquadrate (0); twice as long anteroposteriorly as broad transversely (1).
34. Pedal digit I, phalangeal length: digit I-ph 1+2 longer than (0), or subequal to (1), digit III-ph 1
Coelurosauria
35. Maxillary secondary palate: insignificant (0); substantial (1).
36. Frontal with deep cerebral fossa: absent (0); present (1).
37. Antorbital fossa, maximum width of anterior margin: 20-30% (0), or 40-50% (1), of maximum length of the antorbital fossa.
38. Ectopterygoid pneumatic excavation, shape: anteroposteriorly elongate (0); subcircular (1).
39. Sacral vertebrae, number: three (0); five (1); six or more (second sacrodorsal attached to preacetabular process) (2).
40. Elongate caudal prezygapophyses, distribution: CA25 (0), or CA15 (1), and more distal caudal vertebrae.
41. Iliac preacetabular fossa, development on pubic peduncle: along anterior margin (0); over most of the peduncle (1).
42. Ischium, maximum length: 80-100% (0), 60-70% (1), or 50% or less (2), pubis length.
43. Ischial obturator flange, shape: trapezoidal (0); triangular (1).
44. Pubic obturator opening, form: foramen (0); notch (1).
45. Femoral fourth trochanter, form: crescentic flange (0); low crest or rugosity (2).
46. Fibular fossa, size: occupying part (0), or all (1), of medial aspect of proximal end.
47. Feathers (or feather-like filaments): absent (0); present (1).
Maniraptoriformes
48. Pterygopalatine fenestra: absent (0); present (1).
49. Pterygoid mandibular ramus: broad flange (0); short process (1).
50. Postaxial cervical centra, form of anterior face: strongly convex (0); weakly convex or flat (1).
51. Mid cervical (C4-8) rib length: longer than (0), or subequal to (1), centrum length.
52. Posterior chevron blades, shape: dorsoventrally (0), or anteroposteriorly (1), elongate.
53. Sternal lateral trabecula: absent (0); present (1).
54. Sternal ribs (three pairs): absent (0); present (1).
55. Coracoid posteroventral process, length: length from glenoid lip to tip of posteroventral process equal to (0), or more than twice (1), the diameter of the coracoid glenoid fossa.
56. Semilunate carpal, composition: two carpals (0); single carpal (1).
57. Ischial obturator notch, shape: circular or U-shaped with parallel sides (0); U-shaped with divergent sides (1).
58. Pubic ischial peduncle, ventral flange: present (0); absent (1).
59. Astragalar condyles, position of transverse axis: ventral to articular cup for tibia (0); ventral to ascending process (1).
60. Astragalar condyle, transverse groove below anterior rim: present (0); absent (0).
61. Astragalar ascending process, position of dorsomedial edge: low-angle crossing (0); high-angle crossng (1); parallels medial margin of tibia (2).
Tyrannoraptora
62. Lacrimal-frontal contact: absent (0); present (1).
63. Quadrate height: 70-90% (0), or 40-50% (1), of the height of the skull at mid-orbit.
64. Coracoid dorsoventral length: 2-3 times (0), or 5 times or more (1), coracoid glenoid diameter.
65. Radial distal end: subcylindrical (0); flattened anteroposteriorly (1).
66. Iliac pubic peduncle, orientation of distal end: sloping posteroventrally (0); horizontal (1).
67. Iliac supraacetabular crest, transverse width: semicircular (0), or straight (1), lateral margin in dorsal view of the ilium.
68. Ischial foot: present (0); absent (1).
69. Femoral anterior trochanter, height: shorter (0), or as tall as (1), greater trochanter.
70. Anterior and greater trochanters, position of junction: near base (0), or distal end (1), of anterior trochanter.
71. Calcaneum, distal articular width: 20-25% (0), or 10% (1), of maximum transverse width of astragalus.
Maniraptora
72. Lacrimal ventral process, orientation: laterally (0), or anteriorly (1), directed.
73. Jugal anterior process, shape: expanded anteriorly (0); tapered anteriorly (1).
74. Laterosphenoid head, size: large (0); small, synovial joint small or absent (1).
75. Uncinate ossifications on several dorsal ribs: absent (0); present (1).
76. Sternal anterior margin: rounded (0); slotted for coracoid (1).
77. Acromion height (distance from axis of blade): 50% or more (0), or 40% or less (1), of the distance from the central axis of the blade to the acromion.
78. Humeral deltoid depression, shape: narrow (0); broad triangular (1).
79. Olecranon process: present (0); absent (1).
80. Ulna, articular surface for humerus, shape: anteroposteriorly elongate (0), or equilateral (1), triangle.
81. Ulna, articular surface for humerus, form: undivided (0); low intercondylar crest (1).
82. Ulna, shaft curvature: straight (0); bowed transversely away from radius (1).
83. Ulna, shape of distal end: transverse width approximately 1.5 (0), or 3.0 (1), times maximum anteroposterior depth.
84. Metacarpal I, medial extent of anterior rim of carpal trochlea: terminates on proximomedial corner (0); extends distally down medial margin (1).
85. Metacarpal I, position of medial condyle: level with (0), or positioned dorsal to (1), lateral condyle.
86. Iliac postacetabular process, shape: trapezoidal (0); half-crescentic (1).
87. Ischial obturator notch, size: less (0), or greater (1), than anteroposterior diameter of acetabulum.
88. Femoral fourth trochanter, shape: crescentic flange (0); low crest or rugosity (1).
89. Femoral distal end, anterior muscle scar: present (0); absent (1).
90. Tibial malleoli: present (0); absent (1).
91. Astragalus, surface for medial half of distal end of tibia, form: cupped (0); flat (1).
92. Astragalus, anterior vascular fossa: present (0); absent (1).
93. Vaned feathers (rachis, barbs, barbules): absent (0); present (1).
Paraves
94. Lacrimal ventral ramus, orbital and antorbital separation: rugose margin (0); smoothly confluent surface (1).
95. Lacrimal posterior process: absent (0); present (1).
96. Prefrontal: present (0); rudimentary or absent (1).
97. Postorbital medial process, orientation: anteriorly directed (0); anterodorsally directed (1).
98. Pterygopalatine fenestra, size: slit-shaped (0); broad fenestra (1).
99. Pterygoid palatal ramus, width: one-fifth (0), or one-tenth (1), length.
100. Laterotemporal fenestra, dorsoventral diameter: subequal to (0), or less than 75% of (1), dorsoventral diameter of the orbit.
101. Dentary posterior process dorsal to external mandibular fenestra: present (0); absent (1).
102. Trunk length: 150% or more (0), or 125% or less (1), of femur length.
103. Caudal vertebrae, position with posteriormost neural spine: CA20-30 (0); CA11-12 (1).
104. Coracosternal articulation, extent: medial portion (0), or all (1), of the anterior margin of the sternum.
105. Coracoid anteroventral margin, shape: arcuate (0); straight (1).
106. Acromion position: dorsal (0), or anterior (1), to the glenoid fossa (with the central axis of the scapular blade held horizontal).
107. Scapular blade, distal expansion: 160% or more (0), 130% or less (1), of minimum width of blade (proximal neck).
108. Metacarpal II, distal condyle proportions: subequal (0); medial condyle broader transversely, deeper dorsoventrally, longer distally than lateral condyle (1).
109. Metacarpal III, proximal heel on base: absent (0); present (1).
110. Metacarpal III shaft axis: straight (0); bowed laterally (1).
111. Manual phalanges III-1+2, length: longer (0), or shorter (1), than phalanx III-3.
112. Iliac peduncles, ventral projection: subequal (0); pubic peduncle extends ventral to ischial peduncle (1).
113. Ischium, form of shaft mid section: rod-shaped or oval (0); subplanar (1).
114. Ischial symphysis, area: entire distal end (0); only ventral edge of distal end (1).
115. Femoral posterior trochanter: absent (0); present (1).
116. Metatarsals III, IV, size of distal condyles: unexpanded (0); bulbous (1).
117. Metatarsal III, separation of distal condyles: undivided (0); divided (1).
118. Pedal digit II, hyperextendable claw: absent (0); present (1).
Spinosauroidea
119. Maxillary anterior ramus, length: 70% (0), or 100% or more (1), of maximum depth.
120. Lacrimal anterior ramus, length: more (0), or less (1), than 65% of the ventral ramus.
121. Humeral deltopectoral crest, length: less (0), or more (1), than 45% humeral length.
122. Radial (forearm) length: more (0), or less (1), than 50% of humeral length.
123. Manual digit I-ungual, length: approximately 250% (0), or 300% (1), the depth of the proximal end.
Allosauroidea
124. Nasal, participation in antorbital fossa: absent (0); present (1).
125. Palatine, flange-shaped articular process for lacrimal: absent (0); present (1).
126. Quadrate, articular flange for quadratojugal: rudimentary or absent (0); present (1).
127. Pneumatic fossa around opening for the internal carotid artery: absent (0); present (1).
128. Basioccipital, participation in basal tubera: present (0); absent (1).
129. Articular, pendant medial process: absent (0), present (1).
Ornithomimosauria
130. Subnarial foramen: present (0); absent (1).
131. Maxilla, preantorbital ramus length: less (0), or equal to or more (1), than 50% of the length of antorbital fossa.
132. Antorbital fossa, form of ventral margin: rounded crest (0); invaginated (1).
133. Nasal anteroventral process: present (0); absent (1).
134. Internal mandibular fenestra: present (0); reduced to a narrow slit or absent
135. Surangular ridge dorsal to posterior surangular foramen: present (0); absent (1).
136. Metacarpal I, length: less than 40% (0), approximately 50% (1), or 60% or more, of metacarpal II length.
137. Metacarpal-phalangeal joint, maximum extension: approximately 45ƒ(0), or 15ƒ or less (metacarpal distal extensor pits absent) (1), above the horizontal.
Ornithomimoidea
138. Premaxilla, shape of internarial process: transversely (0), or dorsoventrally (1), flattened.
139. Prefrontal exposure on dorsal skull roof: less (0), or more (1), than the lacrimal.
140. Prefrontal orbital flange: absent (0); present (1).
141. Dentary length: 60-70% (0), or 80% (1), of lower jaw length.
142. Implantation, maxillary and dentary tooth rows, i: separate alveoli (0); groove in maxilla and dentary (1).
143. Maxillary tooth row, posteriormost tooth: directly above or posterior to (0), or significantly anterior to (1), posteriormost maxillary tooth.
144. Tooth size along maxillary and dentary tooth rows: increasing to a maximum near the anterior end (0); uniform (1).
145. Crown size, upper and lower tooth rows: dentary crowns subequal in size (0), or smaller than (1), maxillary crowns.
146. Chevron length: approximately twice (0), or 4-5 times (1), corresponding neural spine height.
147. Metacarpals I-III, extent of shaft-to-shaft contact: metacarpal bases only (0); 60-70% of shafts (1).
148. Manual proximal phalanges, marked flexor depression proximal to distal condyles: absent (0); present (1).
149. Manual proximal phalanges, paired flexor processes: absent (0); present (1).
150. Manual I-1 phalanx, dorsomedial tubercle: absent (0); present (1).
151. Manual unguals, form of ventral surface: transversely rounded and narrow (0); flattened and broad (1).
152. Manual unguals, position of flexor tubercles: proximal (0); displaced distally (2).
153. Iliac blades, separation in midline: erect and separated (0); deflected toward midline with partial contact along dorsal margin (1).
Oviraptorosauria
154. External naris, elevation of ventral margin: at the level of (0), or dorsal to (1), the maxilla.
155. Premaxilla participation in antorbital fossa: absent (0); present (1).
156. Mid-snout length: nasal longer (0), or shorter (1), than frontal.
157. Maxilla, form of ramus along ventral margin of antorbital fossa: flat (0); inset medially for dentary and surangular of lower jaw.
158. Jugal orbital ramus, form of mid-section: transversely compressed (0); rod-shaped (1).
159. Primary palate, position: mostly between (0), or ventral to (1), maxilla and jugal.
160. Dentary dorsal margin, form: straight or gently concave (0); convex (1).
161. External mandibular fnestra, length: 15-20% (0), or 40% (1), length of lower jaw.
162. Caudal vertebrae, proportions of articular faces: witdth and height subequal (0); width twice height (1).
163. Anterior caudal (CA1-8) transverse processes, length: subequal to (0), or approximately twice (1), corresonding neural spines.
164. Acromion, form: dorsal tabular flange (0); everted edge (1); anterior or anterodorsal prong (2).
165. Subacromial notch: absent (0); present (1).
Oviraptoroidea
166. Dentary symphysis, state of articulation: free (0); coossified (1).
167. Dentary anterior end, form: undifferrentiated (1); upturned (1).
168. Dentary rami dorsal and ventral to external mandibular fenestra, depth at mid-length: ventral (0), or dorsal (1), ramus is deeper.
169. Dentary dorsal process for surangular, position: lateral (0), or medial (1), side of lower jaw.
170. Surangular, orientation of coronoid margin: vertical (0); deflected medially (1).
171. Jaw joint, position: far (0), or close (1), to the midline.
172. Articular (and quadrate condylar) width: less (0), or more (1), than twice thickness of surangular.
173. Adductor fossa, anterior margin: present (0); absent (1).
174. Splenial posterior ramus, position on lower jaw: ventral or ventromedial (0): medial (1).
175. Dentary teeth: present (0); absent (1).
176. Pleurocoels, anterior caudal vertebrae: absent (0); present (1).
Deinonychosauria
177. Postorbital ventral process, length: longer than (0), or subequal to (1), posterior process.
178. Parietal-squamosal occipital margin: low (0); plate-shaped (1).
179. Splenial-angular sliding articulation, postion on lower jaw: medial (0); ventral (1).
180. Splenial border of internal mandibular fenestra, shape: arcuate (0); V-shaped (1).
181. Posterior surangular foramen, size: small (0); at least twice primitive diameter (1).
182. Articular posteromedial process: absent (0); present (1).
183. Articular smooth ("vascular") surface, location: medial aspect of articular (0); extends across articular between glenoid and retroarticular faces (1).
184. Articular contact with surangular medial process: non-synovial (0); synovial (1).
185. Mid and posterior chevrons with bifurcate anterior and posterior processes: absent (0); present (1).
Particularly homoplastic characters and homoplasious autapomorphies
186. Premaxillary posterolateral process, length: long, extending onto the side of the snout (0); short, terminating within the narial fossa (1).
187. Upper alveolar margin, anterior end: V-shaped (0); broadly U-shaped (1).
188. Posterior tympanic recess, location: lateral (0), or within (1), the columellar recess.
189. Parasphenoid pneumatic bulla: absent (0); present (1).
190. Lower jaws, form of symphyseal region: V-shaped (0); spout-shaped (1).
191. Coronoid: present (0); absent (1).
192. Crown recurvature: present (0); very reduced or absent (1).
193. Crown size and number: more than 50% depth of dentary ramus, 10-18 teeth (0); less than 25% depth of dentary ramus, 20 or more teeth (1).
194. Crown base: continuous with root (0); wasted (1).
195. Premaxillary teeth: present (0); absent (1).
196. Mid-cervical vertebrae (C3-C7), postzygapophyseal form: short, distal epipophyses (0); long (overhanging) and arched with inset epipophyses (1).
197. Mid- and posterior caudal vertebrae, prezygapophyseal length: elongate, overlapping 30-50% of preceding centrum (0); short (1).
198. Coracoid glenoid: concave (0); flat (1); hemisellar (concave anteroposteriorly) (2); convex (3).
199. Forelimb/hindlimb length: forelimb length 45-60% (0), or 70% or more (1), of hind limb length.
200. Humeral ectepicondyle, size: low crest (0); flared laterally as a process as broad as the distal condyles (1)
201. Supraacetabular crest, posterior end: tapers along acetabulum (0); ends abruptly on lateral aspect of ischial peduncle (1).
202. Femoral anterior trochanter, size: wing-shaped (0); narrow (1); splint-shaped (2)
203. Femoral greater trochanter, anteroposterior width: subequal to (0), or twice or more as broad as (1), femoral head.
204. Metatarsal III with proximal extension on ventral aspect of the distal end: absent (0); present (1).

Data Matrix
Outgroups
HERRERASAURIDAE
00000000000000000X0000000000000000000X00000000000100X00X0000000000010000000X0000000000X00000?0000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000X00?0000000000X00
CERATOSAURIA
00000000000000000X0000000000000000000X10000000?00000000X000000000000000000000000000000X00000?000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000010000000000000000
Ingroups
TORVOSAURIDAE
11??1?111111111100010???00????000?000??000000????000??0?0000000000000?000???0000000000X00000?00000000000000000000000001111100000000000010000000000000000000000?0?0000000??00000000000000000?00?0000000000000
SPINOSAURIDAE
11110111111111??00????0?10?0??000?100?1?000000???0????0?0000000000000000??0?0000000??0X00000?000000000000000000000000011111000000100000??01000000000000001000000000000000000000000000000000X00?0000000000000
ALLOSAURIDAE
1111111111111111111111111111111111000010000100?00000X0000000101000000000000X0000000000X00000?0000000000000000000000000000001111110000000000000000000000000000000000000000000000000000000000X0000000000000000
SINRAPTORIDAE
11101111111111111111111(01)11?1?1111100001000000??0000?00??00000000?000000000000????????0X00000?000000000000000000000000000???111111000000?000000000000000000000000000000000000000000000000000X00?0000000000000
COMPSOGNATHIDAE
1?1??1111111?1??1?1?1??101?1111111??1?1011111?1??000X00?0????000000000?00?0X0?000000?00?????00000??0?01?000?0000000000000000?0????000??1????000000000000000000000000000????00000000?????000?00?000001000000?
Ornitholestes
111?1?11111111111111111111????111??11111111111??00?0????00???00??00??0?000???0000000000?00???0000000001????????00000000000?000??0000001?0000000000?00?0000000001000??0000000000000000000000?00?000000?00000? Deltadromeus
???????111111111????????01?1???????????1??1111????????0???001??0??0?000?????00000??????10000?????000?00000??????000000??0????????????????????????0??????0????????0000??????????0????????0???????????00?00000 THERIZINOSAURIDAE
001??1011112?1110X00010001?11111?011112X11X11X11111???1011111000001000100???0?0000000000000000000000000?000000?0000000000000000001111111100000000000000000000000000000000000000000000000000?1111011010110110
ALVAREZSAURIDAE
001?1X111112111110000?X0010111?111111?2X11?11X?110110011?1110000000100101?000000000000010000?00010000000000000000000000000000000011111111111111111111111100001000000000000000000000000000101011111?110011110
ORNITHOMIMIDAE
0011111111121111100001X0010111111111111111111111111111111111100000000010110?0X00000000010000000010000000000000100000000000000000011111111111111111111111100000000100000000000000000000000010(01)1?0110100000000
TYRANNOSAUROIDEA
1111111111121121111111111111111111111121111101?11001??111111111111111110000X0000000000000000?000000000000000000000000000000000000000000000000000000000001000000000000000000000000000000000100000000000001001
Caudipteryx
??1?11111112X1111???????1111111111?11?1112111?1??101001111111?11111111111???1111111111111111100000000000000000?011000000000000000?01?00000??000001000000011111111112100000?0??1000?00???000?01?0010113000110
CAENAGNATHIDAE
?????1?1?????????1?????01????1????1???2??211?????1??????11?????????1????????????????0111111?????????0?0?0????0?01100000???000??00101?00000??0XXXX??00000011111111?1??11111111111??0X0000?00X011XX01?1????000
OVIRAPTORIDAE
10X111111112?111110X10X01111111111111X2X121111?011111111111111111111111111111111111111111111?000000000000000000011000000000000000001000000000XXXX1000000011111111112111111111111000X0000000?011XX01113000110
TROODONTIDAE
0011111111121121110X11?111?111?111?11121121111?11111??11111111111111111111??1111111111111111?1111111111111111110111111000000000000000000000000000000000000000000000000000000000011111111111X11?010010?000211
DROMAEOSAURIDAE
1111111111121111111111111111111111?111211211111111111111111111111111111111111111111111111111?111111111111111111111111100000000000000000000000000000000000000000000010000000000001111111110000000000003100200
AVES
00111111X112?1111?0X01X00111111111?1111112111?1111011111111111111111111111(01)11111111111111111111111111111111111111111110000000000000000000000000000000000000000000002000000000000000000000001001100000(12)100X00

9--Basal Aves
This dataset includes 99 characters in 4 basal avian taxa, with Deinonychosauria and Oviraptorosauria serving as successively more remote outgroups.

Characters and Character-States
Aves
1. Prenarial snout, length: shorter (0), or longer (1), than maximum snout height.
2. External nares, diameter: shorter (0), or longer (1), than horizontal diameter of the antorbital fenestra.
3. Crown ornamentation: serrations (0); vestigial serrations or absent (1).
4. Crown base form: unconstricted (0); constricted (1).
5. Caudal vertebrae, number: more than 23 (0); 23 or fewer (1).
6. Furcula, maximum shaft width: narrower (0), or broader (1), than minimum width of the neck of the scapular blade.
7. Glenoid midpoint, orientation: posteroventral and slightly lateral (0); lateral (1).
8. Scapular blade, orientation of axis: anteroventral to (0), or nearly parallel with (1), the axis through the anterior and mid-dorsal vertebral column.
9. Coracoid shape: medial (0), or lateral (1), margin longer.
10. Scapular acromial process, shape: flange-shaped (0); quadrangular or pyramidal process (1).
11. Corocoid ventral deflection: less (0), or equal to or more (1), than 90ƒ.
12. Coracoid biceps tubercle, position: inset from (0), or along (1), the ventral margin of the coracoid.
13. Coracoid ventral fossa: present (0); absent (1).
14. Semilunate carpal, height: 30-35% (0), or 50% (1), of maximum transverse width.
15. Manual I-1 phalanx, shaft width: subequal to (0), or more slender than (1), metacarpal II.
16. Manual II-1 and -2 phalanges, shaft shape: subcylindrical (0); subtriangular (1).
17. Metacarpals II, III, and phalanges II-1, III-1, collateral ligament pits: present (0); absent (1).
18. Metacarpal III, proximal shaft shape: subcylindrical (0); strap-shaped (1).
19. Manual digits II and III, distal articulation: absent (0); present (1).
20. Manual digits II and III, relative position: parallel (0); digit III crosses under digit II (1).
21. Acetabular medial wall: absent (0); partial wall formed by flange from the pubic peduncle of the ilium (1).
22. Pedal I-ungual, direction of tip: posteromedial (0); anteromedial (reversed) (1).
23. Vaned feathers, distribution: primary, secondary, rectrix only (0); primary secondary, rectrix, covert, contour (1).
Ornithurae
24. Premaxillary posteromedial process, location of posterior tip: near posterior margin of external nares (no frontal contact) (0); posterior to external nares (frontal contact) (1).
25. Mid-cervical centra , form of articular faces: amphiplaytan (0); heterocoelic (1).
26. Sacral vertebrae, number: 6 (0); 8 or more (1).
27. Free caudal vertebrae: 23 or more (0), 6 (1).
28. Pygostyle: absent (0); present (1).
29. Cervical ribs, attachment: free (0); fused (1).
30. Cervical rib shaft, form: subcylindrical (0); flattened (1).
31. Cervicodorsal rib transition: gradual (0); abrupt (1).
32. Furcular proximal articular end, form: rounded (0); club-shaped (1).
33. Scapular acromial process, orientation of long axis: anterior (0); anterodorsal (1).
34. Coracoid shape, anterior view: subrectangular (0); subtriangular with constricted shaft proximally (1).
35. Coracoid foramen, location: centered on coracoid (0); medial margin of coracoid (1); embayment along medial margin or absent (2).
36. Ulnar shaft, maximum mid-shaft diameter: subequal (0), or 70% or more (1) that of the radius.
37. Humeral distal condyles, position: distal (0); anterior (1).
38. Ulna-radius and proximal carpals, configuration: carpals located distally (0), or shifted laterally (1), relative to the distal ends of the ulna and radius.
39. Radius, proximal articular surface for ulna: flattened facet on shaft (0); raised platform distinct from shaft (1).
40. Semilunate carpal-metacarpal I, II, articulation: open (0); coossified (1).
41. Semilunate carpal-metacarpal I articulation, extent of contact: entire proximal end of metacarpal I (0); one-half proximal end of metacarpal I (1); absent (2).
42. Manual II-1 phalanx, lateral shaft form: convex (0); excavated with lateral flange (1).
43. Ischial obturator process: present (0); absent (1).
44. Ilioischial fenestra: absent (0); present (1).
45. Tibia and proximal tarsals, articulation: free (0); completely coossified (1).
46. Distal tarsals and metatarsals, articulation: free (0); completely coossified (1).
47. Metatarsus, anterior tuber: absent (0); present (1).
Ornithothoraces (Enantiornithes + Euornithes)
48. Premaxillary posteromedial processes, articulation: free (0); coossified (1).
49. Ectopterygoid: present (0); absent (1).
50. Hypapophyses in posterior cervical and anterior dorsals: crest-shaped (0); pendant (1).
51. Dorsal vertebrae, number: about 15 (0); 11 or less (1).
52. Anterior dorsal vertebrae, form of transverse processes: rod-shaped (0); plate-shaped (1).
53. Caudal transverse processes, length: subequal to (0), or longer than (1), respective chevrons.
54. Caudal transverse processes, relative length: decrease posteriorly (0); increase posteriorly (1).
55. Dorsal ribs, size distribution: D3 though mid-dorsals subequal (0); D3 largest, decreasing posteriorly (1).
56. Gastralia: present (0); absent (1).
57. Sternal length: shorter (0), or subequal (1), to scapular length.
58. Sternal keel: absent (0); present (1).
59. Sternal trabecula, form: subquadrate (0); strap-shaped with distal flare (1).
60. Sternal trabecula, orientation: lateral and slightly posterior (0); posterior and slightly lateral (1).
61. Furcula and coracoid, length: 50% (0), or at least 80% (1), length of scapula.
62. Intrafurcular angle: greater (0), or less (1), than 70ƒ.
63. Hypocleideum: absent (0); present (1).
64. Hypocleideum, shape: anteroposteriorly (0), or transversely (1), compressed.
65. Scapula-coracoid articulation, form: flat (0); pit-tuber (1).
66. Coracoid shape (lateral view): inverted-L (0); straight (1).
67. Coracoid, acrocoracoid process (biceps tubercle), size: tubercle (0); robust process (1).
68. Triosseal canal (furcula-acrocoracoid articulation): absent (0); present (1).
69. Coracoid, acrocoracoid process (biceps tubercle), location: ventral (0), or dorsal (1), to glenoid.
70. Coracoid, glenoid form: concave, subcircular (0); convex, oval (1).
71. Coracoid, glenoid orientation: posterolateral (0); lateral (1).
72. Humeroulnar length ratio: greater (0), or less (1), than 1.0.
73. Ulnar biceps tubercle: absent (0); present (1).
74. Ulnar distal end, articular rim for ulnare: absent (0); present (1).
75. Radius, lateral groove on mid shaft: absent (0); present (1).
76. Ulna-radiale articulation: absent (0); present (1).
77. Ulnare size: small (0); large (subequal to distal ulna or radius) (1).
78. Ulnare, notch for manus: absent (0); present (1).
79. Radiale form: wedge-shaped (0); tabular (1).
80. Manual digit I, length: 50% (0), or 30% (1), of length of digit II.
81. Manual digit II, length: longer (0), or shorter (1), than forearm or humerus.
82. Manual digit II, diameter: subequal to (0), or nearly twice (1), diameter of corresponding elements of digit I.
83. Manual II-2 phalanx, shaft shape: cylindrical (0); subtriangular, excavated (1).
84. Manual II-2 phalanx, length: longer (0), or shorter (1), than II-1 phalanx.
85. Metacarpal III, length: slightly shorter (0), or slightly longer (1), than metacarpal II.
86. Metacarpal III, distal flexor process: absent (0); present (1).
87. Manual III-1 phalanx, shaft form: subcylindrical (0); excavated, expanding distally (1).
88. Manual III-2, -3, -ungual phalanges: present (0); absent (1).
89. Iliac antitrochanter on acetabular margin: weak or absent (0); prominent (1).
90. Ischial length: less than 50% (0), or 75% or more (1), of the length of the pubis.
91. Pubic symphysis, extent: along ventral half (0), or distal end (1), of pubic shaft.
92. Tibial fibular trochanter, shape: semilunate (0); subtriangular (1).
93. Fibula distal end, form: rod-shaped (0); splint-shaped, terminating before tarsus (1).
94. Metatarsal I distal condyles, position: proximal to (0), or opposite (1), those of metatarsals II-IV.
95. Pedal digit II, hyperextension and ungual size/shape: present, largest, more recurved (0); absent, smaller than digit III-ungual, similar recurvature (1).
96. Metatarsal V: present (0); absent (1).
97. Pedal unguals, flexor tubercle size: strong (0); weak (1).
98. Alular feathers: absent (0); present (1).
Particularly homoplastic character
99. External mandibular fenestra: present (0); absent (1).

Data Matrix
Outgroups
OVIRAPTOROSAURIA
00000000000000000000000000000000X0000000000000000000000000000010000000000000000000000000000000100X0
DEINONYCHOSAURIA
00000000000000000000000000000000X0000000000000000000000000000000000000000000000000000000000000000X0
Ingroups
Archaeopteryx
1111111111111111111111100000000000000000000000000000000000XX000XX0000000000000000000000000000000001
Confuciusornis
11XX111111111111111111111111111111111111111111100000??000000000XX0000000000000000000000000000000000
ENANTIORNITHES
111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111111110
EUORNITHES
111111111111111111111111111111110111111111111111111111111111111111111111111111111111111111111111111

References

  1. P. C. Sereno, N. Jb. Geol. Palƒontol. Abh. (in review).
  2. D. L. Swofford, PAUP (v. 3.1), IL Natural History Survey (1993).
  3. P. C. Sereno, J. Vert. Paleontol. Suppl. (1991); P. C. Sereno and A. B. Arcucci, J. Vert. Paleontol.13, 385 (1993); ibid.14, 53 (1994).
  4. P. C. Sereno, in M. Benton, E. Kurochkin, M. Shishkin, D. Unwin, Eds., The Age of Dinosaurs in Russia and Mongolia (Cambridge Univ. Press, Cambridge, in press).
  5. J. A. Wilson and P. C. Sereno, J. Vert. Paleontol. Suppl.15, 1 (1998).