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However, such descriptions was basically predicated on remote teeth together with positional analysis was indeed hypothesized using ornithischian dinosaurs since an unit

callenderi had been well-discussed (Heckert, 2002 ; Seem, 1989 ; See & Lucas, 1994 ; Padian, 1990 ). That have several tooth hit issue within-situ teeth now lets a refinement away from earlier in the day functions. Search ( 1989 ) is best within the identifying premaxillary white teeth off maxillary pearly whites. Yet, pearly whites like those throughout the premaxilla (Rates 4e, f), characterized by are symmetrical mesiodistally and lingually curved at apex, are based in the prior portion of the dentary. Maxillary (Figures 4g, h) and you will dentary pearly whites (Contour 5d) into the ranking rear with the third tooth are nearly symmetric mesiodistally, but often is actually lingually rounded on top, labiolingually compressed, and possess large extended crowns. The shape of the maxillary and dentary pearly whites varies positionally versus an effective discernable development, perhaps pertaining to tooth replacement.

One’s teeth off R

This new anterior deal with of the atlantal intercentrum was broken away, nevertheless the posterior half the new function try well preserved. Inside the bookofmatches nasД±l kullanД±lД±yor rear see (Profile 8c), new ability are subrectangular having slight dorsoventral constrictions across the midline. The new atlantal intercentrum was concave dorsally in which they articulates towards the atlantal pleurocentrum. It articulates to the axial pleurocentrum with an apartment saddle-shaped skin (Contour 8d). Brand new ventral facial skin of atlantal intercentrum is actually excavated by the good strong despair bordered because of the a sharp prior ridge. The fresh horizontal body try incised by a-deep dorsoventrally established sulcus one curves anteriorly during the its dorsal the amount. Both the lateral and you may ventral anxiety are not utilized in phytosaurs (age.g., Machaeroprosopus mccauleyi, PEFO 31219), where in fact the atlantal intercentrum is if you don’t much like compared to Roentgen. callenderi.

5.six.1 Atlas-axis state-of-the-art

The atlantal pleurocentrum, intercentrum, and neurapophysis occur (Rates 8a–c). The brand new prezygapophysis of one’s atlantal neurapophysis is a small anteriorly-projecting circular projection (Contour 8a). From inside the phytosaurs (age.g., PEFO 31219) and you will crocodylomorphs (Brochu, 1992 ), the fresh new prezygapophysis increases a whole lot more laterally. The new postzygapophysis try long and you will surge-instance and you can systems posterodorsally. Stretching medially throughout the zygapophyses was a general slim flange you to forms the fresh new roof of your own sensory canal.

The brand new atlantal pluerocentrum (Contour 8b) try crescentic within the prior and you may rear viewpoints, unlike into the phytosaurs, in which it’s square within the anterior view (age.g., PEFO 31219). The anterior and you will posterior counters is actually convex, though the anterior articular face are a bit flatter and you will greater than just the new posterior articular face. Brand new rear articular deal with and contains a low dorsoventrally trending sulcus you to definitely is also utilized in phytosaurs (age.g., PEFO 31219). This new dorsal epidermis of the atlantal pleurocentrum are concave and you may mediolaterally two times as wider while the anteroposteriorly long. Proportionally, new atlantal pleurocentrum away from R. callenderi try anteroposteriorly quicker than the exact same element in L. meadei (TMM 31185–97) and you can T. coccinarum (AMNH 7634), if you don’t they are quite similar.

5.5 Postcrania Remote and you will related postcranial elements are common on quarries from the PFV 297 and PFV 414. The best-preserved bones is the fact out of PEFO 34561, that may deliver the basis for the fresh repair (Shape 7) and description, along with other specimens complementing the fresh new breakdown in which indexed. 5.six Axial bones

The newest axial intercentrum isn’t understood of one specimen. The newest axial pleurocentrum (Figure 8d) regarding Roentgen. callenderi is approximately equant within the dimensions. The brand new anterior articular deal with try dorsally concave where it articulates that have the brand new atlantal elements; ventral compared to that town brand new articular deal with was apartment and you may mountains posteroventrally in which it could articulate to the axial intercentrum. The fresh new lateral edges of the prior articular face of your own axial pleurocentrum is actually stretched while the margins abut for the parapophyses. The latest parapophyses have flat articular counters, is actually raised into distinct pedestals, and you may deal with posterolaterally. This new diapophyses mode a rounded area one faces posterolaterally and you may somewhat ventrally. The lateral skin of the centrum and contains a-deep fossa rear towards the parapophysis. So it fossa was proportionally deeper than in L. meadei (TMM 31185-97) otherwise T. coccinarum (AMNH 7634), although the breadth associated with fossa changes as a consequence of ontogeny in other archosaurs (Irmis, 2007 ) that’s absent in some aetosaurs (Desojo ainsi que al., 2012 ). The latest ventral facial skin of your axis centrum and also a sharp average ventral keel. This might be missing within the L. meadei.

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