5.dos.13 Squamosal
The fresh morphology and laterally up against direction of squamosal may be very like aetosaurs including S. robertsoni, Good. ferratus, P. andressorum, and you may D. spurensis (Shape 4u, v; Walker, 1961 : fig. 2; Small, 2002 : fig. 2; Schoch, 2007 : fig. 8; Schoch & Desojo, 2016 : fig. 4). This new unusually-molded squamosal (named “sword-like” getting An excellent. ferratus of the Schoch clover incelemesi, 2007 ) models the fresh posterodorsal margin of one’s supratemporal fenestra. T. ruthae comes with an excellent sideways centered squamosal; not, R. callenderi and aetosaurs do not have the obvious ventral projection utilized in you to definitely taxon (Ezcurra ainsi que al., 2017 ).
The fresh squamosal bears around three techniques, a keen anterior procedure, an effective posterodorsal procedure, and you can a posteroventral techniques. The newest mediolaterally thin anterior techniques is the largest of the around three and articulates ventrally towards quadratojugal, models a small portion of the posterodorsal margin of the lateral temporary fenestra, and you will articulates dorsally to the posteroventral edge of new postorbital. A horizontal ridge into dorsal portion of the squamosal bounds the newest supratemporal fenestra sideways and you will goes on anteriorly on the dorsolateral margin of the postorbital. A little anteriorly directing top of anterior process of the fresh squamosal underlies a beneficial posterodorsal projecting prong of one’s dorsal procedure of the fresh jugal. This get in touch with excludes the new postorbital out-of involvement on margin from new infratemporal fenestra as previously mentioned previously, similar to the condition in P. kirkpatricki (Weinbaum, 2011 ), and various throughout the symptom in aetosaurs (elizabeth.g., P. andressorum, Schoch & Desojo, 2016 ). A small slot to your anteroventral skin of your own anterior procedure fits a thinner dorsal process of the new quadratojugal.
The fresh rear part of the squamosal extends posterior into direct of your quadrate and you may divides towards the a posteroventral and you can an enthusiastic anterodorsal processes. Your head of your quadrate suits toward a distinct ventrally facing fossa one to offers onto the prior an element of the posteroventral procedure (Shape 4v); thus, this new posteroventral procedure as well as the horizontal edge of the fresh articulation skin covers your face of your quadrate away from horizontal evaluate. At exactly the same time, for the posteroventral osal, there is a condo, posteriorly up against shelf that accepts the fresh thin anterodorsal margin of one’s quadrate. The new rear facial skin of posteroventral processes features a little facet one articulates with the paroccipital process of the opisthotic (Figure 4v). In lieu of very archosauriforms, that it factors try thickened mediolaterally and rounded into the a penis similar into symptom in T. dabanensis (IVPP V3237) and aetosaurs (Nesbitt, 2011 ). New posterodorsal procedure carries a great slit into the its rear line one to fits the latest posterolateral process of new parietal.
One of the bones of your palate, the brand new vomers are not acknowledged from any known specimen. Although not, the new ectopterygoid, pterygoid, and you may palatine try kept from inside the PEFO 34561 and an extra ectopterygoid is known (PEFO 33857); the newest palate is finished but blurred for the PEFO 34089 (Figure three dimensional).
5.2.fourteen Pterygoid
In the event none are entirely preserved (Contour 5a), this new pterygoid consists of brand new anterior process, lateral processes, and you will rear techniques. The newest anterior process are triangular in cross-section with a high dorsal ridge you to definitely distills brand new function within the latest midline. The fresh new ventral skin of the procedure try concave. They tapers anteriorly nevertheless the exposure to the fresh palatine was not familiar. Brand new lateral processes include an excellent posteriorly indicated wing that slopes posteroventrally. The new horizontal portion of the ventral skin features an enormous part across the whole duration of new lateral process that articulates having the latest dorsal surface of your own ectopterygoid (Shape 5a). The new pterygoid person is a thin, vertically situated knife. The ventral epidermis bears a circular anteroposteriorly mainly based ridge one to continues on onto the prior techniques. Pterygoid teeth try missing. New rear procedure (= quadrate processes) is actually broken in all specimens (elizabeth.g., PEFO 34561) rear toward articulation area on the partial-rounded fossa into basipterygoid process of the fresh parabasisphenoid. Brand new anteroposterior period of new pterygoid is similar to you to definitely when you look at the archosauriforms eg Erythrosuchus africanus (Gower, 2003 ) and you may P. kirkpatricki (TTU P-9000), as opposed to the anteroposteriorly abbreviated pterygoids from aetosaurs (age.g., L. meadei, TMM 31185-98; Neoaetosauroides engaeus, PVL 5698).
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