Although not, this type of definitions was in fact centered on separated white teeth and also the positional study was in fact hypothesized using ornithischian dinosaurs while the an unit

Although not, this type of definitions was in fact centered on separated white teeth and also the positional study was in fact hypothesized using ornithischian dinosaurs while the an unit

callenderi were really-demonstrated (Heckert, 2002 ; Take a look, 1989 ; Look & Lucas, 1994 ; Padian, 1990 ). Having several enamel hit issues within-situ teeth now allows a sophistication out-of past work. Seem ( 1989 ) was right inside differentiating premaxillary white teeth regarding maxillary pearly whites. Yet ,, white teeth like those from the premaxilla (Numbers 4e, f), characterized by getting shaped mesiodistally and you will lingually rounded at the apex, also are found in the prior portion of the dentary. Maxillary (Rates 4g, h) and you will dentary pearly whites (Shape 5d) within the positions rear on the third enamel are almost symmetrical mesiodistally, but often is lingually rounded at the top, labiolingually compacted, and also highest expanded crowns. The shape of maxillary and you can dentary teeth varies positionally instead of an effective discernable trend, maybe regarding tooth replacement.

The teeth away from R

New anterior face of atlantal intercentrum try busted out, although posterior 1 / 2 of the fresh new function are well preserved. During the posterior look at (Shape 8c), new ability is actually subrectangular having slight dorsoventral constrictions along the midline. The latest atlantal intercentrum try concave dorsally in which it articulates on atlantal pleurocentrum. It articulates towards the axial pleurocentrum with an apartment saddle-molded facial skin (Contour 8d). Brand new ventral body of your atlantal intercentrum was excavated of the a beneficial strong anxiety bordered by a sharp prior ridge. This new lateral skin are incised because of the an intense dorsoventrally based sulcus that shape anteriorly on its dorsal the amount. Both lateral and you can ventral depression commonly found in phytosaurs (age.g., Machaeroprosopus mccauleyi, PEFO 31219), in which the atlantal intercentrum try or even very similar to that Roentgen. callenderi.

5.six.step 1 Atlas-axis cutting-edge

The fresh new atlantal pleurocentrum, intercentrum, and you will neurapophysis exists (Rates 8a–c). The newest prezygapophysis of your own atlantal neurapophysis try a tiny anteriorly-projecting round projection (Profile 8a). In the phytosaurs (e.g., PEFO 31219) and you can crocodylomorphs (Brochu, 1992 ), the prezygapophysis increases even more sideways. The postzygapophysis was a lot of time and spike-eg and you may ideas posterodorsally. Stretching medially on the zygapophyses was a general slim flange one forms the new rooftop of your own neural canal.

The fresh new atlantal pluerocentrum (Profile 8b) try crescentic in the prior and you will rear views, in the place of inside phytosaurs, where it’s rectangular within the anterior have a look at (e.grams., PEFO 31219). The prior and you may rear surfaces try convex, though the prior articular deal with try slightly flatter and wide than just this new posterior articular deal with. The fresh rear articular face features a shallow dorsoventrally trending sulcus one to is additionally found in phytosaurs (elizabeth.grams., PEFO 31219). The latest dorsal body of one’s atlantal pleurocentrum is concave and you may mediolaterally doubly greater as the anteroposteriorly long. Proportionally, this new atlantal pleurocentrum out of Roentgen. callenderi was anteroposteriorly quicker compared to exact same aspect in L. meadei (TMM 31185–97) and you will T. coccinarum (AMNH 7634), if not he’s quite similar.

5.5 Postcrania Isolated and you may related postcranial aspects are on the quarries at PFV 297 and you will PFV 414. The best-kept bones is that out of PEFO 34561, which will deliver the reason for the brand new reconstruction (Figure 7) and you may malfunction, together with other specimens supplementing the malfunction where noted. 5.six Axial bones

The fresh axial intercentrum is not recognized from any sample. The newest axial pleurocentrum (Figure 8d) away from Roentgen. callenderi is approximately equant within its size. This new anterior articular face are dorsally concave where it articulates with the fresh new atlantal factors; ventral compared to that area brand new articular deal with are apartment and you may hills posteroventrally in which it could articulate into axial intercentrum. The fresh new horizontal corners of your prior articular deal with of your axial pleurocentrum was expanded once the margins abut on parapophyses. The latest parapophyses keeps flat articular counters, was raised towards collection of pedestals, and you may face posterolaterally. The fresh diapophyses function a rounded part you to definitely face posterolaterally and you can slightly ventrally. The brand new lateral facial skin of one’s centrum and has a-deep fossa posterior on the parapophysis. It fossa was proportionally better than in L. meadei (TMM 31185-97) otherwise T. coccinarum (AMNH 7634), even though the breadth on the fossa change due to ontogeny in other archosaurs (Irmis, 2007 ) and is missing in some aetosaurs (Desojo mais aussi al., 2012 ). New ventral facial skin of your own axis centrum and has a sharp median ventral keel. It is missing in the L. meadei.

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