callenderi have been well-discussed (Heckert, 2002 ; Look, 1989 ; Appear & Lucas, 1994 ; Padian, 1990 ). Which have multiple enamel impact issue with in-situ teeth today allows a sophistication from prior performs. Appear ( 1989 ) is correct inside distinguishing premaxillary pearly whites off maxillary white teeth. Yet ,, pearly whites such as those from the premaxilla (Numbers 4e, f), described as are symmetrical mesiodistally and you will lingually curved at the apex, are found in the prior portion of the dentary. Maxillary (Numbers 4g, h) and you may dentary pearly whites (Profile 5d) when you look at the ranking rear on the third enamel are practically symmetrical mesiodistally, however, possibly was lingually rounded from the top, labiolingually compacted, and also have high stretched crowns. The design of one’s maxillary and you can dentary teeth varies positionally in the place of a good discernable trend, perhaps associated with tooth substitute for.
The teeth off R
The brand new prior face of one’s atlantal intercentrum is actually busted away, although rear 50 % of the brand new ability was well-preserved. Inside the rear evaluate (Shape 8c), the fresh element was subrectangular which have moderate dorsoventral constrictions along the midline. Brand new atlantal intercentrum is concave dorsally where they articulates into atlantal pleurocentrum. They articulates to your axial pleurocentrum having a condo saddle-shaped skin (Contour 8d). The ventral facial skin of your atlantal intercentrum try excavated because of the an excellent deep despair bordered of the a sharp anterior ridge. The latest lateral surface is incised of the a deep dorsoventrally founded sulcus one shape anteriorly from the its dorsal the amount. Both the lateral and you can ventral anxiety are not used in phytosaurs (age.grams., Machaeroprosopus mccauleyi, PEFO 31219), the spot where the atlantal intercentrum is otherwise nearly the same as that of R. callenderi.
5.6.step one Atlas-axis advanced
This new atlantal pleurocentrum, intercentrum, and you will neurapophysis exists (Figures 8a–c). The brand new prezygapophysis of the atlantal neurapophysis is actually a little anteriorly-projecting round projection (Shape 8a). Within the phytosaurs (e.g., PEFO 31219) and you may crocodylomorphs (Brochu, 1992 ), this new prezygapophysis increases alot more laterally. The newest postzygapophysis is enough time and you can increase-for example and you may systems posterodorsally. Stretching medially on zygapophyses is actually a standard slim flange that forms new roof of neural tunnel.
The new atlantal pluerocentrum (Contour 8b) was crescentic inside the anterior and you can rear viewpoints, rather than for the phytosaurs, where it’s rectangular within the prior have a look at (elizabeth.grams., PEFO 31219). Both the prior and you will posterior counters are convex, though the anterior articular face is actually slightly compliment and you may large than just this new rear articular face. The brand new posterior articular deal with and contains a low dorsoventrally trending sulcus one to is additionally found in https://datingranking.net/tr/cheekylovers-inceleme/ phytosaurs (age.grams., PEFO 31219). The latest dorsal skin of your atlantal pleurocentrum is concave and you will mediolaterally doubly wider given that anteroposteriorly long. Proportionally, new atlantal pleurocentrum away from R. callenderi was anteroposteriorly faster compared to same aspect in L. meadei (TMM 31185–97) and T. coccinarum (AMNH 7634), if not he’s quite similar.
5.5 Postcrania Isolated and you may related postcranial aspects are common throughout the quarries at the PFV 297 and you can PFV 414. An informed-managed bones is the fact off PEFO 34561, that deliver the reason behind this new reconstruction (Shape 7) and malfunction, along with other specimens complementing the brand new breakdown in which detailed. 5.6 Axial bones
Brand new axial intercentrum isn’t identified out-of one sample. The axial pleurocentrum (Figure 8d) off Roentgen. callenderi is roughly equant in dimensions. The fresh anterior articular deal with is actually dorsally concave where it articulates with the atlantal aspects; ventral to that area the articular deal with was flat and you can mountains posteroventrally where it could articulate for the axial intercentrum. The brand new lateral edges of your own prior articular face of your own axial pleurocentrum try offered as margins abut on the parapophyses. The new parapophyses features apartment articular counters, try raised on distinct pedestals, and you will face posterolaterally. The new diapophyses setting a bent section you to confronts posterolaterally and you may slightly ventrally. The fresh new lateral epidermis of centrum and contains an intense fossa posterior toward parapophysis. That it fossa try proportionally better than in L. meadei (TMM 31185-97) or T. coccinarum (AMNH 7634), even though the depth with the fossa transform owing to ontogeny in other archosaurs (Irmis, 2007 ) and that’s missing in a number of aetosaurs (Desojo mais aussi al., 2012 ). The ventral surface of axis centrum and has a-sharp median ventral keel. This is certainly missing in the L. meadei.
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