not, these types of definitions have been according to separated pearly whites as well as the positional studies had been hypothesized having fun with ornithischian dinosaurs because a model

not, these types of definitions have been according to separated pearly whites as well as the positional studies had been hypothesized having fun with ornithischian dinosaurs because a model

callenderi had been well-demonstrated (Heckert, 2002 ; Appear, 1989 ; Seem & Lucas, 1994 ; Padian, 1990 ). That have several enamel results issue with in-situ pearly whites today lets a refinement of early in the day functions. See ( 1989 ) are correct into the identifying premaxillary white teeth of maxillary white teeth. Yet, white teeth like those on the premaxilla (Figures 4e, f), characterized by being symmetric mesiodistally and lingually curved from the apex, are also based in the prior part of the dentary. Maxillary (Numbers 4g, h) and you may dentary teeth (Shape 5d) in ranks rear into 3rd enamel are practically shaped mesiodistally, but both try lingually rounded at top, labiolingually compacted, and now have high longer crowns. The form of maxillary and you can dentary pearly whites may differ positionally without a great discernable trend, maybe related to enamel replacement for.

One’s teeth from Roentgen

The newest prior face of the atlantal intercentrum was broken away, however the posterior half of the latest feature was well-preserved. For the posterior see (Figure 8c), the latest function was subrectangular that have slight dorsoventral constrictions along the midline. The brand new atlantal intercentrum try concave dorsally in which they articulates toward atlantal pleurocentrum. They articulates towards the axial pleurocentrum having an apartment seat-molded skin (Shape 8d). This new ventral surface of the atlantal intercentrum was excavated by good deep despair bordered by a sharp prior ridge. The latest horizontal surface is incised of the a-deep dorsoventrally oriented sulcus you to shape anteriorly in the their dorsal the quantity. Both the horizontal and you will ventral despair are not found in phytosaurs (age.g., Machaeroprosopus mccauleyi, PEFO 31219), in which the atlantal intercentrum try if you don’t nearly the same as compared to R. callenderi.

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

The fresh atlantal pleurocentrum, intercentrum, and you may neurapophysis can be found (Numbers 8a–c). The brand new prezygapophysis of your atlantal neurapophysis was a little anteriorly-projecting game projection (Contour 8a). In phytosaurs (age.g., PEFO 31219) and you may crocodylomorphs (Brochu, 1992 ), the new prezygapophysis develops alot more sideways. The newest postzygapophysis is much time and surge-such as and projects posterodorsally. Stretching medially about zygapophyses try a broad slim flange you to definitely variations new rooftop of the neural tunnel.

The brand new atlantal pluerocentrum (Figure 8b) are crescentic when you look at the anterior and posterior views, as opposed to into the phytosaurs, in which it is square into the anterior consider (e.g., PEFO 31219). The anterior and you will rear surfaces was convex, even though the anterior articular deal with is actually slightly compliment and you may wider than just the fresh new posterior articular deal with. The Bu linkte bir gГ¶z atД±n latest posterior articular deal with features a low dorsoventrally popular sulcus you to definitely is also included in phytosaurs (e.grams., PEFO 31219). The newest dorsal facial skin of one’s atlantal pleurocentrum try concave and you may mediolaterally doubly greater once the anteroposteriorly enough time. Proportionally, new atlantal pleurocentrum off R. callenderi was anteroposteriorly less versus exact same element in L. meadei (TMM 31185–97) and you can T. coccinarum (AMNH 7634), otherwise he’s much the same.

5.5 Postcrania Separated and associated postcranial issue are typical on quarries from the PFV 297 and PFV 414. An educated-preserved bones would be the fact away from PEFO 34561, that provide the reason for brand new repair (Figure 7) and you will description, together with other specimens complementing the newest description where detailed. 5.six Axial bones

The newest axial intercentrum isn’t understood regarding people specimen. New axial pleurocentrum (Figure 8d) out of R. callenderi is approximately equant within the proportions. The newest prior articular face try dorsally concave where it articulates having the fresh new atlantal elements; ventral to this area this new articular deal with is apartment and you may slopes posteroventrally in which it would articulate on the axial intercentrum. New lateral edges of your prior articular face of the axial pleurocentrum is actually lengthened just like the margins abut into the parapophyses. The newest parapophyses features flat articular counters, is elevated into the collection of pedestals, and you can deal with posterolaterally. The fresh diapophyses mode a bent section you to faces posterolaterally and a bit ventrally. Brand new lateral body of one’s centrum features a-deep fossa rear for the parapophysis. That it fossa was proportionally greater compared to L. meadei (TMM 31185-97) otherwise T. coccinarum (AMNH 7634), though the breadth regarding the fossa alter as a consequence of ontogeny in other archosaurs (Irmis, 2007 ) and that’s missing in certain aetosaurs (Desojo et al., 2012 ). The ventral facial skin of the axis centrum and contains a sharp median ventral keel. This will be missing in the L. meadei.

not, these types of definitions have been according to separated pearly whites as well as the positional studies had been hypothesized having fun with ornithischian dinosaurs because a model callenderi had been well-demonstrated (Heckert, 2002 ; Appear, 1989 ; Seem & Lucas, 1994 ; Padian, 1990 ). That have several enamel results issue with in-situ…

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