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Although it is nearly complete, the skull of IVPP V 12534 is extremely compressed transversely, obscuring the medial surfaces of most of the cranial elements (Fig. 3.1); the dorsal surface of the skull roof is visible in only right lateral view (Fig. 3.1A). Some pieces, including the predentary, rostral ramus of the right dentary, rostral ends of both premaxillae, the articulated right postorbital and squamosal, and the left paroccipital process can be separated from the rest of the skull and described in greater detail. See You, Luo, et al. (2003:348–350, fig. 1C) for a reconstruction and measurements of the fully assembled skull. See Appendix 3.1 for additional cranial and postcranial measurements of IVPP V 12534.

Premaxilla and Nasal The oral margin of the premaxilla is gently convex and edentulous (Fig. 3.2A, B). The rostral end of the premaxilla is ventrally inflected relative to the ventral margin of the maxilla, such that the oral margin is positioned well below the maxilla (Fig. 3.2A, B). The caudolateral corner of the oral margin curves caudodorsally towards the rostroventral process of the maxilla (Fig. 3.2A). The oral margin of each premaxilla expands laterally to form a transversely broad snout (Fig. 3.2C, D). Each premaxilla bears two rostrocaudally elongate denticles on its oral margin (Fig. 3.2D), as in Mantellisaurus (NHMUK R5764), Ouranosaurus (cast of MNHN GDF 300), and Eolambia (CEUM 35635). Caudal to the denticles, the ventral surface of the premaxilla is flat and somewhat rugose along the interpremaxillary suture (Fig. 3.2D). Dorsal to the oral margin, the lateral surface of the premaxilla is concave, forming the rostral end of the narial fossa (Fig. 3.2A, B).

Caudodorsal to the narial fossa, the premaxilla splits into two processes, the dorsomedial and ventrolateral processes; the point at which these processes diverge forms the rostral margin of the external naris (Fig. 3.2A, B). The dorsomedial process is overlapped laterally by the premaxillary process of the nasal, which forms the dorsal margin of the external naris (Figs. 3.2A, B, 3.3, 3.4). The dorsomedial processes of the left and right premaxillae meet along the interpremaxillary suture (Fig. 3.2C). The ventrolateral process forms the ventral margin of the external naris and contacts the maxilla along its ventral margin, curving over the rostroventral process of the maxilla and extending caudally to contact the lacrimal and prefrontal (Figs. 3.2A, 3.3, 3.4). The ventrolateral process also contacts the prefrontal in Hippodraco (McDonald, Kirkland, et al., 2010), Theiophytalia (Brill and Carpenter, 2006), Dakotadon (Weishampel and Bjork, 1989), Iguanodon bernissartensis (Norman, 1980), Mantellisaurus (Norman, 1986), and Jinzhousaurus (Barrett et al., 2009), but does not in Altirhinus (Norman, 1998) or Xuwulong (You et al., 2011). The ventrolateral process tapers towards its caudal end, as in Hippodraco (McDonald, Kirkland, et al., 2010), Dakotadon (Weishampel and Bjork, 1989), Iguanodon (Norman, 1980), and Mantellisaurus (Norman, 1986) in contrast to the dorsoventrally expanded ventrolateral processes of more derived hadrosauroids such as Eolambia (Kirkland, 1998; Head, 2001) and Probactrosaurus gobiensis (Norman, 2002) (Figs. 3.3, 3.4). The ventrolateral process contacts the nasal along its dorsal margin (Figs. 3.3, 3.4). The ventrolateral process of the premaxilla and the nasal contribute equally to the caudal margin of the external naris.

The nasal contacts the premaxilla rostrally and ventrally, the prefrontal ventrally, the frontal caudally, and its counterpart medially (Figs. 3.3, 3.4). Rostral to its contact with the ventrolateral process of the premaxilla, the ventral margin of the nasal curves rostrodorsally toward the dorsomedial process of the premaxilla, forming the dorsal margin and part of the caudal margin of the external naris. The sutures between the nasals and frontals are difficult to discern due to damage and compression of the skull; their shape is not certain (Figs. 3.3, 3.4).

3.2. Articulated premaxillae of IVPP V 12534, holotype of Equijubus normani. (A) right premaxilla in lateral view; (B) left premaxilla in lateral view; (C) premaxillae in dorsal view; (D) same in ventral view. Abbreviations: bf, bone fragment; dmp, dorsomedial process; en, external naris; ips, interpremaxillary suture; md, marginal denticles; nf, narial fossa; om, oral margin; pmxp, premaxillary process of nasal; rvp, rostroventral process of right maxilla; vlp, ventrolateral process. Scale bar equals 10 cm.

Maxilla, Palatine, and Pterygoid The rostroventral process of the maxilla curves rostroventrally to contact the ventrolateral process of the premaxilla (Figs. 3.2A, 3.3, 3.4). There is a short diastema between the rostral end of the rostroventral process and the first alveolus. The presence of a rostrodorsal process cannot be ascertained due to the articulation of the premaxillae with the maxillae of IVPP V 12534. The ventral margin of the maxilla is gently concave in lateral view (Figs. 3.3, 3.4). The lateral surface of the maxilla is pierced by several deep, irregularly distributed neurovascular foramina dorsal to the tooth row and near the dorsal margin of the maxilla (Figs. 3.3A, 3.4A), as in Dakotadon (SDSM 8656; Weishampel and Bjork, 1989).

The ascending process of the maxilla is rostrocaudally broad and triangular, and contacts the ventrolateral process of the premaxilla and the lacrimal along its rostral margin, and the maxillary process of the jugal along its caudal margin (Figs. 3.3, 3.4). The antorbital fossa is not visible in lateral view. The jugal process of the maxilla is finger-like and projects caudolaterally to lock into a recess on the medial surface of the maxillary process of the jugal (Fig. 3.5), as in Iguanodon bernissartensis (Norman, 1980), Mantellisaurus (Norman, 1986), Altirhinus (Norman, 1998), Probactrosaurus gobiensis (Norman, 2002), and Eolambia (Kirkland, 1998; CEUM 34356).

The right palatine and right and left pterygoids are partially visible through the orbits and infratemporal fenestrae of IVPP V 12534 (Figs. 3.3, 3.4). However, due to damage and the overlap of other cranial elements, little can be determined regarding their morphology. The caudal alar processes of the right pterygoid can be identified and are in contact with the braincase and the medial wing of the right quadrate (Fig. 3.4).

3.3. Skull of IVPP V 12534, holotype of Equijubus normani. (A) skull in left lateral view; (B) tracing of the skull in left lateral view. Solid black lines indicate sutures and contacts between cranial bones; dashed lines indicate uncertain sutures and contacts. Predentary, rostral ramus of right dentary, rostral ends of the premaxillae, articulated right postorbital and squamosal, and the left paroccipital process have been removed. Abbreviations: bc, braincase; boc, basioccipital; cp, coronoid process of the left dentary; en, external naris; flp, finger-like process of the maxillary process of the left jugal; fo, fenestra ovalis; hy, hyoid; lan, left angular; ld, left dentary; lexo, left exoccipital; lf, left frontal; lj, left jugal; ll, left lacrimal; lmx, left maxilla; lna, left nasal; lpmx, left premaxilla; lpo, left postorbital; lpoc, left paroccipital process; lprf, left prefrontal; lpt, left pterygoid; lsa, left surangular; mf, metotic foramen; oc, occipital condyle; p, parietal; rd, right dentary; rf, right frontal; rq, right quadrate; rsa, right surangular; rvp, rostroventral process of left maxilla; V, VII, and XII, foramina for cranial nerves V, VII, and XII. Scale bars equal 10 cm.

3.4. Skull of IVPP V 12534, holotype of Equijubus normani. (A) skull in right lateral view; (B) tracing of the skull in right lateral view. Solid black lines indicate sutures and contacts between cranial bones; dashed lines indicate uncertain sutures and contacts. Predentary, rostral ramus of right dentary, rostral ends of the premaxillae, and the left paroccipital process have been removed. The articulated right postorbital and squamosal were left in place. Abbreviations: bc, braincase; cap, caudal alar process of the right pterygoid; cp, coronoid process of the right dentary; en, external naris; flp, finger-like process of the maxillary process of the right jugal; lf, left frontal; lmx, left maxilla (rostroventral process); lna, left nasal; lpo, left postorbital; lprf, left prefrontal; lpt, left pterygoid; p, parietal; pqf, paraquadrate foramen; ran, right angular; rd, right dentary; rf, right frontal; rj, right jugal; rl, right lacrimal; rmx, right maxilla; rna, right nasal; rpal, right palatine; rpmx, right premaxilla (ventrolateral process); rpo, right postorbital; rprf, right prefrontal; rpt, right pterygoid; rq, right quadrate; rqj, right quadratojugal; rsa, right surangular; rsq, right squamosal; vb, vertical buttress; vfj, ventral flange of right jugal. Scale bars equal 10 cm.

3.5. Left maxilla-jugal articulation of IVPP V 12534, holotype of Equijubus normani. Abbreviations: jp, jugal process of maxilla; mxp, maxillary process of jugal. Scale bar equals 10 cm.

Jugal The maxillary process of the jugal tapers to a point and extends rostrally to meet the apex of the ascending process of the maxilla (Figs. 3.3, 3.4). The contact between the maxillary process and the lacrimal is unusually complex; a finger-like process arises from the maxillary process and appears to overlap the lateral surface of the lacrimal (Figs. 3.3, 3.4). This feature is present on both sides of the skull and has not been observed in any other iguanodontian, and therefore is an autapomorphy of Equijubus normani. Many other basal iguanodonts exhibit a tapering maxillary process, such as Mantellisaurus (NHMUK R11521), Altirhinus (Norman, 1998), Jinzhousaurus (Barrett et al., 2009), and Xuwulong (You et al., 2011), but the dorsal margin of the maxillary process is smooth and lacks the finger-like process of Equijubus. The maxillary process of the jugal widens abruptly caudal to the autapomorphic finger-like process and forms the ventral margin of the orbit. The dorsal and ventral margins of the maxillary process are parallel between the rostroventral margin of the orbit and the base of the postorbital process (Fig. 3.5). The postorbital process of the jugal projects caudodorsally and meets the stouter jugal process of the postorbital, forming the caudal margin of the orbit (Figs. 3.3, 3.4). Caudoventral to the base of the postorbital process, the ventral margin of the jugal is sinuous with a rounded, ventrally directed flange ventral to the infratemporal fenestra (Fig. 3.4). Caudal to this flange, the jugal abruptly expands dorsoventrally, giving off a dorsally directed process that forms part of the caudal margin of the infratemporal fenestra and excludes the quadratojugal from the fenestra (Fig. 3.4).

Lacrimal and Prefrontal The rostral ramus of the lacrimal tapers to a point, wedging between the maxilla and the ventrolateral process of the premaxilla (Figs. 3.3, 3.4); the rostral ramus also tapers in Dakotadon (SDSM 8656) and Xuwulong (You et al., 2011). The rostral ramus of the lacrimal is elongated in IVPP V 12534, extending along the dorsal margin of the maxilla to terminate rostral to the apex of the ascending process of the maxilla. This morphology has not been observed in other iguanodonts and is an autapomorphy of Equijubus; in other iguanodonts–such as Iguanodon (Norman, 1980), Altirhinus (Norman, 1998), Shuangmiaosaurus (You, Ji, et al., 2003), Jinzhousaurus (Barrett et al., 2009), and Xuwulong (You et al., 2011)–the rostral ramus of the lacrimal does not extend along the dorsal surface of the maxilla rostral to the apex of the ascending process. The ventral margin of the lacrimal is very slightly concave dorsally between its rostral end and the aforementioned finger-like process of the jugal. Caudal to the finger-like process of the jugal, the ventral margin of the lacrimal is convex ventrally (Figs. 3.3, 3.4). The caudal margin of the lacrimal is concave to form the rostral margin of the orbit. The caudal extension of the ventrolateral process of the premaxilla excludes the lacrimal from contact with the nasal.

3.6. Articulated right postorbital and squamosal of IVPP V 12534, holotype of Equijubus normani. (A) lateral view; (B) medial view. Abbreviations: gl, glenoid; jp, jugal process of postorbital; j/po, jugal-postorbital contact; ls, lateral shelf; lsf, laterosphenoid facet; orr, orbital rim; popj, postorbital process of jugal; pops, postorbital process of squamosal; poq, postquadrate process; po/sq, postorbital-squamosal contact; prq, prequadrate process; sqp, squamosal process of postorbital. Scale bar equals 10 cm.

Due to the articulated nature of the skull, damage to the right prefrontal, and severe deformation of the left prefrontal, little can be determined regarding the anatomy of this element. The prefrontal comprises the rostrodorsal margin of the orbit. Rostral to the orbital rim, the nasal process of the prefrontal is dorsoventrally expanded (Figs. 3.3, 3.4).

Postorbital and Squamosal The postorbital forms the caudodorsal margin of the orbit (Figs. 3.3, 3.4). The orbital rim is rugose (Fig. 3.6A). Rostromedial to the orbital rim, the postorbital meets the frontal along an almost straight suture (Figs. 3.3, 3.4). The jugal process of the postorbital projects rostroventrally to contact the postorbital process of the jugal (Figs. 3.3, 3.4, 3.6A). The squamosal process arches dorsally and projects caudally to meet the postorbital process of the squamosal (Figs. 3.4, 3.6A). The caudal end of the squamosal process is rounded and overlaps the lateral surface of the squamosal. The medial surface of the postorbital bears a shallow facet that would articulate with the rostral end of the laterosphenoid (Fig. 3.6B).

3.7. Braincase elements of IVPP V 12534, holotype of Equijubus normani. (A) distal portion of left paroccipital process in medial view; (B) braincase in caudal view. Abbreviations: boc, basioccipital; fm, foramen magnum; lexo, left exoccipital; ppoc, pendant portion of paroccipital process; rexo, right exoccipital. Scale bar equals 10 cm.

The postorbital process of the squamosal bears a rounded shelf on its lateral surface, forming the origin site for M. adductor mandibulae externus superficialis (Ostrom, 1961; Fig. 3.6A). Dorsal to this shelf, the lateral surface of the postorbital process is gently convex dorsally and slopes dorsomedially. Caudal to the postorbital process, two prongs, the prequadrate and postquadrate processes, project ventrally rostral and caudal to the glenoid that would receive the dorsal condyle of the quadrate (Figs. 3.4, 3.6A). The morphology of the caudomedial process of the squamosal cannot be ascertained due to crushing.

3.8. Predentary of IVPP V 12534, holotype of Equijubus normani. (A) predentary in dorsal view; (B) same in ventral view; (C) same in left lateral view; (D) same in right lateral view. Abbreviations: bdm, base of dorsomedial process; brl, broken base of right lobe of ventromedial process; dg, groove for contact with dentary; ll, left lobe of ventromedial process; md, marginal denticle; mmd, median marginal denticle; rg, groove on rostral surface. Scale bar equals 10 cm.

Quadratojugal and Quadrate The quadratojugal is a narrow sliver of bone wedged between the caudal end of the jugal and the lateral wing of the quadrate (Fig. 3.4). The quadratojugal does not overlap the notch in the lateral wing of the quadrate but instead forms the rostral margin of an open paraquadrate foramen.

The quadrate gradually curves caudally along its entire length in lateral view (Fig. 3.4). The ventral condyle of the quadrate is mediolaterally broad and rostrocaudally narrow, with an enlarged lateral condylar surface compared to the medial condyle surface. Approximately one-third of the way up of the quadrate from the ventral condyle is the semicircular quadratojugal notch in the lateral wing of the quadrate (Fig. 3.4); as stated above, the paraquadrate foramen is open, as in Iguanodon bernissartensis (Norman, 1980), Mantellisaurus (Norman, 1986), and Altirhinus (Norman, 1998). The medial wing of the quadrate is obscured by the lateral wing. Immediately ventral to the dorsal condyle of the quadrate is a distinct vertical buttress on the caudal margin of the quadrate (Fig. 3.4).

Neurocranium Due to the compression and articulation of the skull and–in the case of the lateral surface of the braincase–surface damage to the bone, the morphology and sutural relationships of the neurocranium are difficult to ascertain. The midline interfrontal suture is visible on the skull roof, as are the left and right frontoparietal sutures perpendicular to it (Fig. 3.4). The frontal participates in the dorsal rim of the orbit. The only suture discernible on the lateral surface of the braincase is that between the left exoccipital and the basioccipital (Fig. 3.3). The lateral wall of the braincase is pierced by five foramina: the fenestra ovalis, the metotic foramen, and the foramina for cranial nerves V, VII, and XII.

The left paroccipital process is preserved, and its distal portion can be detached from the rest of the skull (Fig. 3.3). The distal portion of the paroccipital process is pendant, with the straight pendant portion directed ventrally (Fig. 3.7A). The caudal aspect of the braincase is visible, although compression of the skull means that the sutures between the supraoccipital and the exoccipitals cannot be discerned. The ventral margin of the foramen magnum is formed exclusively by the left and right exoccipitals; the basioccipital is excluded (Fig. 3.7B). The occipital condyle is directed caudoventrally. The basioccipital bears a rostrocaudally oriented groove on its ventral surface.

Predentary Like the rest of the skull and mandible, the predentary has suffered marked transverse compression, rendering its true overall shape ambiguous (Fig. 3.8A, B); both of the lateral processes of the predentary appear to project caudally, but it cannot be determined whether they were divergent or parallel to each other. The lateral surfaces of the lateral processes are flat, whereas the medial surfaces are convex (Fig. 3.8C, D). The lateral processes taper at their caudal ends in all views (Fig. 3.8A–D). The ventral surface of each lateral process bears an elongated groove that narrows caudally, forming the contact surface for the rostral ramus of the dentary (Fig. 3.8B).

The dorsal margin of each lateral process bears a row of at least four marginal denticles; four intact denticles are present on the left lateral process, whereas all the denticles on the right lateral process are broken at their bases (Fig. 3.8A, C, D). The median denticle is not broken and is the tallest denticle on the predentary. The median denticle and the intact denticles on the left lateral process are rostrocaudally compressed, subtriangular prongs (Fig. 3.8C), as in Altirhinus (Norman, 1998) and Probactrosaurus gobiensis (Norman, 2002). Ventral to the denticles on each lateral process is a row of deep neurovascular foramina that extends along the lateral surface of the lateral process parallel to the denticle row and penetrates to the medial surface of the predentary (Fig. 3.8A, C, D). On the rostral surface of the predentary, ventrolateral to the median denticle, are two grooves that extend dorsomedially to ventrolaterally (Fig. 3.8C).

Although part of the ventromedial process is missing, it is clear that it was bifurcated into two ventrolaterally directed lobes, as indicated by the unbroken edges of the preserved left lobe (Fig. 3.8C); this is akin to the predentaries of Altirhinus (Norman, 2002) and Xuwulong (You et al., 2011), but differs from the non-bifurcated ventromedial process of Jinzhousaurus (Barrett et al., 2009). The left lobe of the ventromedial process is triangular with a rounded apex (Fig. 3.8C). The broken base of the dorsomedial process is visible between the lateral processes (Fig. 3.8A).

Dentary The left dentary of IVPP V 12534 is missing its rostral ramus, but the right dentary is complete, and its rostral ramus can be removed for closer inspection (Fig. 3.9A–C). At its rostral end, the dentary exhibits a shallow groove for articulation with the right lateral process of the predentary (Fig. 3.9A). There is a short and mediolaterally compressed diastema caudal to this predentary groove, forming a sharp margin between the predentary groove and the first alveolus (Fig. 3.9C). Medial to the predentary groove, the symphysis projects medially to form a rugose horizontal shelf (Fig. 3.9B, C). The symphysis is oriented rostrolaterally to caudomedially relative to the lateral surface of the dentary in dorsal view (Fig. 3.9C). Caudal to the symphysis is a shallow furrow, the Meckelian groove, which deepens caudally (Fig. 3.9B). The lateral surface of the dentary is pierced by several large neurovascular foramina, with two foramina on the ventrolateral surface of the dentary caudal to the symphysis and a row of irregularly spaced foramina that extends parallel to the tooth row (Fig. 3.9A, D).

The dorsal and ventral margins of the dentary are parallel in lateral view, with a ventrally inflected ventral margin that curves towards the symphyseal region (Fig. 3.9D), as in Iguanodon bernissartensis (Norman, 1980), Mantellisaurus (Norman, 1986), Altirhinus (Norman, 1998), Probactrosaurus gobiensis (Norman, 2002), and Eolambia (Kirkland, 1998). This differs from the straight dentaries of Penelopognathus (Godefroit et al., 2005), Lanzhousaurus (You et al., 2005), Jinzhousaurus (Barrett et al., 2009), and Xuwulong (You et al., 2011). The ventral margin also curves ventrally near the caudal end of the dentary, beginning approximately at the 11th dentary tooth position, and forms a ventrally convex bulge ventral to the base of the coronoid process (Fig. 3.9D). The coronoid process itself arises from another, laterally convex bulge on the lateral surface of the dentary, which begins approximately at the 13th tooth position (Fig. 3.9D). The coronoid process of the left dentary is better exposed than that of the right dentary due to breakage of the left jugal. The coronoid process projects vertically and is rostrocaudally expanded near its apex; the coronoid process attains its greatest rostrocaudal width ventral to its apex (Fig. 3.3).

Surangular and Angular From the coronoid process, the dorsal margin of the surangular slopes caudoventrally toward the glenoid fossa in which the ventral condyle of the quadrate sits (Fig. 3.9E). Rostroventral to the glenoid fossa, the lateral surface of the surangular is pierced by a small surangular foramen (Fig. 3.9E). Caudal to the glenoid fossa, the surangular curves caudodorsally to form the articular process. The angular is visible in lateral view and contacts the ventral margin of the surangular along a horizontal suture (Fig. 3.3).

Hyoids The left and right hyoids are preserved, but only slivers of them can be observed due to compression of the skull.

Dentition The dentary tooth crowns are mesiodistally broad and oblong, as in more basal iguanodontians such as Altirhinus (Norman, 1998), Iguanodon (Norman, 1980), and Kukufeldia (McDonald, Barrett, and Chapman, 2010). The dentary teeth bear numerous ridges on their lingual surfaces, with a distally offset primary ridge, a similarly prominent secondary ridge mesial to the primary, and multiple less prominent accessory ridges arising from the marginal denticles mesial and distal to the primary and secondary ridges (Fig. 3.10A, B). The marginal denticles are tongue shaped with mammilated edges, and steadily increase in size from the apex of the crown to its base (Fig. 3.10A). There is only one replacement tooth per alveolus, and only one active tooth per alveolus to contribute to the occlusal plane.

3.9. Right dentary and surangular of IVPP V 12534, holotype of Equijubus normani. (A) rostral ramus of right dentary in lateral view; (B) same in medial view; (C) same in dorsal view; (D) right dentary with rostral ramus attached in lateral view; (E) right surangular in lateral view. Abbreviations: ap, articular process; dia, diastema; gf, glenoid fossa; lcb, bulge at base of coronoid process on lateral surface of dentary; Mg, Meckelian groove; pdg, groove for predentary; saf, surangular foramen; sym, symphysis; vcb, bulge ventral to base of coronoid process along ventral margin of dentary; vcq, ventral condyle of quadrate. Scale bars equal 10 cm.

3.10. Dentition of IVPP V 12534, holotype of Equijubus normani. (A) dentary teeth in lingual view; (B) tracing of best-preserved dentary tooth (topmost tooth in [A]) in lingual view; (C) maxillary teeth in labial view; (D) tracing of representative maxillary tooth (fourth from left in [C]) in labial view. Abbreviations: dacr, distal accessory ridge; macr, mesial accessory ridge; md, marginal denticle; prr, primary ridge; sr, secondary ridge. Scale bars equal 1 cm.

Examples of unworn maxillary teeth are not visible in IVPP V 12534; however, the worn crowns visible in labial view are lozenge shaped (Fig. 3.10C). The maxillary teeth bear multiple ridges on their labial surfaces, with a distally offset primary ridge. There are several faint accessory ridges mesial to the primary ridge (Fig. 3.10C, D). As is the case for the dentary teeth, only one maxillary tooth per alveolus forms part of the occlusal plane. The morphology of the marginal denticles cannot be discerned.

The numbers of tooth positions in the dentaries and maxillae cannot be ascertained due to overlap of the caudal ends of these elements by the coronoid processes and jugals (Figs. 3.3, 3.4). There are 18 active dentary teeth exposed in the right dentary; the active teeth of the left dentary are largely hidden under the left active maxillary teeth. There are 18 active teeth visible in the right maxilla, and 20 in the left maxilla.

3.11. Representative cervical vertebrae of IVPP V 12534, holotype of Equijubus normani. (A–D) cervical 3 in (A) cranial view, (B) caudal view, (C) right lateral view, and (D) detail of epipophyses and postzygapophyses in oblique dorsal–right lateral view; (E) cervical 4 in right lateral view; (F) cervicals 7 to 9 in left lateral view; (G–I), cervical 10 in (G) cranial, (H) caudal and (I) right lateral view. Abbreviations: cap, capitulum of cervical rib; dia, diapophysis; epi, epipophysis; lam, lamina; para, parapophysis; pozy, postzygapophysis; przy, prezygapophysis; tp, transverse process. Scale bars equal 5 cm.