Although not, such meanings was basically based on remote pearly whites while the positional studies was indeed hypothesized playing with ornithischian dinosaurs just like the a model

Although not, such meanings was basically based on remote pearly whites while the positional studies was indeed hypothesized playing with ornithischian dinosaurs just like the a model

callenderi was really-described (Heckert, 2002 ; See, 1989 ; Appear & Lucas, 1994 ; Padian, 1990 ). With several tooth affect facets with in-situ teeth now lets an elegance away from earlier in the day functions. Look ( 1989 ) is actually right in identifying premaxillary teeth from maxillary pearly whites. Yet, pearly whites such as those in the premaxilla (Rates 4e, f), described as getting symmetric mesiodistally and lingually curved from the top, are also found in the prior part of the dentary. Maxillary (Numbers 4g, h) and you will dentary white teeth (Contour 5d) in ranking rear on the third tooth are almost symmetric mesiodistally, however, sometimes was lingually rounded during the top, labiolingually compacted, and have large extended crowns. The shape of the maxillary and you can dentary pearly whites varies positionally in place of a beneficial discernable pattern, perhaps about enamel substitute for.

One’s teeth of R

The fresh prior deal with of your own atlantal intercentrum is actually broken aside, however the posterior half the brand new ability is well preserved. In rear examine (Profile 8c), the new ability was subrectangular having slight dorsoventral constrictions along the midline. Brand new atlantal intercentrum is actually concave dorsally where they articulates on the atlantal pleurocentrum. It articulates to the axial pleurocentrum that have an apartment seat-shaped surface (Figure 8d). The fresh ventral body of your own atlantal intercentrum try excavated because of the a beneficial strong depression bordered by a-sharp anterior ridge. The newest lateral facial skin are incised from the an intense dorsoventrally established sulcus you to definitely curves anteriorly at the dorsal the amount. The lateral and you can ventral anxiety aren’t included in phytosaurs (elizabeth.g., Machaeroprosopus mccauleyi, PEFO 31219), where in fact the atlantal intercentrum is actually or even much like regarding R. callenderi.

5.six.1 Atlas-axis cutting-edge

The new atlantal pleurocentrum, intercentrum, and neurapophysis can be found (Rates 8a–c). The brand new prezygapophysis of one’s atlantal neurapophysis is a tiny anteriorly-projecting round projection (Figure 8a). In the phytosaurs (elizabeth.grams., PEFO 31219) and you will crocodylomorphs (Brochu, 1992 ), brand new prezygapophysis increases a lot more sideways. The new postzygapophysis is much time and you can spike-for example and ideas posterodorsally. Stretching medially throughout the zygapophyses try a standard thin flange that forms the fresh roof of your own neural canal.

This new atlantal pluerocentrum (Shape 8b) was crescentic in anterior and you will posterior viewpoints, in the place of from inside the phytosaurs, where it is rectangular inside the anterior see (age.grams., PEFO 31219). Both anterior and you will rear counters is actually convex, even though the anterior articular face is some flatter and you will broad than just the latest posterior articular deal with. The brand new posterior articular deal with and also a low dorsoventrally trending sulcus one to is even found in phytosaurs (elizabeth.g., PEFO 31219). The brand new dorsal body of your atlantal pleurocentrum try concave and you can mediolaterally twice as wider because anteroposteriorly a lot of time. Proportionally, brand new atlantal pleurocentrum off Roentgen. callenderi was anteroposteriorly smaller than the exact same aspect in L. meadei (TMM 31185–97) and you will T. coccinarum (AMNH 7634), if not they are comparable.

5.5 Postcrania Remote and you may associated postcranial issues all are throughout the quarries in the PFV 297 and PFV 414. An informed-maintained bones is the fact regarding PEFO 34561, that will supply the basis for brand new reconstruction (Profile 7) and you can malfunction, with other specimens complementing the latest breakdown in which indexed. 5.six Axial bones

New axial intercentrum isn’t understood of one sample. New axial pleurocentrum (Shape 8d) away from R. callenderi is approximately equant in proportions. The prior articular deal with is actually dorsally concave where it articulates that have the latest atlantal factors; ventral to this city the articular face try apartment and slopes posteroventrally where it might articulate to your axial intercentrum. The brand new lateral corners of one’s anterior articular deal with of axial pleurocentrum was offered as the margins abut to the parapophyses. The fresh parapophyses possess apartment articular counters, are increased on type of pedestals, and you can deal with posterolaterally. The fresh new diapophyses form a circular part one face posterolaterally and you will some ventrally. The new lateral skin of your own centrum and has an intense fossa rear with the parapophysis. It fossa is proportionally higher compared to L. meadei (TMM 31185-97) or T. coccinarum (AMNH 7634), although breadth on the fossa changes as a result of ontogeny various other archosaurs (Irmis, 2007 ) which can be absent in some aetosaurs (Desojo ainsi que al., 2012 ). The ventral surface of your own axis centrum and also a-sharp average ventral keel. This is exactly absent from inside the L. meadei.

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