5.2.thirteen Squamosal
The fresh new morphology and you will sideways facing positioning of your own squamosal may be very like aetosaurs instance S. robertsoni, Good. ferratus, P. andressorum, and you will D. spurensis (Shape 4u, v; Walker, 1961 : fig. 2; Quick, 2002 : fig. 2; Schoch, 2007 : fig. 8; Schoch & Desojo, 2016 : fig. 4). The latest unusually-shaped squamosal (named “sword-like” to own An effective. ferratus from the Schoch, 2007 ) forms the fresh posterodorsal margin of one’s supratemporal fenestra. T. ruthae is served by good sideways built squamosal; but not, Roentgen. callenderi and you will aetosaurs do not have the pronounced ventral projection utilized in that taxon (Ezcurra ainsi que al., 2017 ).
The fresh new squamosal carries three procedure, an prior techniques, good posterodorsal techniques, and you can a great posteroventral techniques. The mediolaterally thin anterior techniques is the largest of one’s around three and you can articulates ventrally to the quadratojugal, versions a little part of the posterodorsal margin of one’s lateral temporal fenestra, and you will articulates dorsally on posteroventral edge of this new postorbital. A horizontal ridge into dorsal portion of the squamosal bounds the newest supratemporal fenestra laterally and you can continues on anteriorly on the dorsolateral margin of postorbital. A small anteriorly pointing top of the anterior means of this new squamosal underlies a great faceflow platinum posterodorsal projecting prong of dorsal procedure for the brand new jugal. That it contact excludes new postorbital away from contribution from the margin off the latest infratemporal fenestra as mentioned previously, similar to the symptom in P. kirkpatricki (Weinbaum, 2011 ), and differing on symptom in aetosaurs (e.g., P. andressorum, Schoch & Desojo, 2016 ). A tiny position to your anteroventral skin of the prior procedure fits a finer dorsal process of the fresh quadratojugal.
The latest posterior part of the squamosal expands rear to the head of your quadrate and splits towards a posteroventral and you may an enthusiastic anterodorsal techniques. Your face of one’s quadrate suits on a definite ventrally facing fossa one to expands onto the anterior a portion of the posteroventral process (Figure 4v); ergo, the fresh new posteroventral processes plus the lateral edge of the new articulation facial skin covers the head of one’s quadrate regarding lateral evaluate. As well, into the posteroventral osal, there can be a condo, posteriorly against shelf that accepts the new thin anterodorsal margin of the quadrate. The fresh rear skin of posteroventral processes features a little factors that articulates on the paroccipital procedure for the opisthotic (Shape 4v). Unlike really archosauriforms, it part was thickened mediolaterally and you will rounded to the a manhood similar for the condition in T. dabanensis (IVPP V3237) and you will aetosaurs (Nesbitt, 2011 ). Brand new posterodorsal process holds an effective slit toward their posterior line one fits the new posterolateral procedure of new parietal.
Among the many bones of palate, the new vomers aren’t acknowledged of any understood specimen. Although not, the brand new ectopterygoid, pterygoid, and you will palatine are maintained during the PEFO 34561 and you may an extra ectopterygoid known (PEFO 33857); the palate is done however, blurry during the PEFO 34089 (Shape 3d).
5.dos.fourteen Pterygoid
Whether or not not one are entirely managed (Figure 5a), the brand new pterygoid consists of brand new anterior techniques, horizontal procedure, and you may rear process. New anterior techniques try triangular into the cross-area that have a high dorsal ridge you to spells out the fresh new function at the the fresh new midline. Brand new ventral skin on the processes is actually concave. It tapers anteriorly nevertheless exposure to the fresh new palatine is unfamiliar. The brand new lateral processes includes a posteriorly pointed side you to slopes posteroventrally. The brand new horizontal part of the ventral surface and it has a giant part over the whole amount of new lateral procedure that articulates having new dorsal epidermis of the ectopterygoid (Figure 5a). This new pterygoid body is a thinner, vertically established blade. The fresh ventral epidermis bears a curved anteroposteriorly dependent ridge you to continues on on the prior process. Pterygoid white teeth is actually absent. The newest posterior techniques (= quadrate procedure) try broken in most of the specimens (age.g., PEFO 34561) rear to your articulation area for the semi-game fossa into basipterygoid procedure of the new parabasisphenoid. New anteroposterior amount of the fresh pterygoid is similar to one to in the archosauriforms such as for example Erythrosuchus africanus (Gower, 2003 ) and you will P. kirkpatricki (TTU P-9000), rather than the anteroposteriorly abbreviated pterygoids of aetosaurs (age.grams., L. meadei, TMM 31185-98; Neoaetosauroides engaeus, PVL 5698).
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