The latest ventral articular body holds a couple of convex surfaces split up by a good concave skin

The latest ventral articular body holds a couple of convex surfaces split up by a good concave skin

5.2.13 Squamosal

The new morphology and you can laterally against orientation of one’s squamosal is quite like aetosaurs eg S. robertsoni, Good. ferratus, P. andressorum, and D. spurensis (Profile 4u, v; Walker, 1961 : fig. 2; Small, 2002 : fig. 2; Schoch, 2007 : fig. 8; Schoch & Desojo, 2016 : fig. 4). The newest strangely-formed squamosal (called “sword-like” to possess A good. ferratus from the Schoch, 2007 ) models the posterodorsal margin of your supratemporal fenestra. T. ruthae has good sideways depending squamosal; although not, Roentgen. callenderi and aetosaurs lack the pronounced ventral projection found in that taxon (Ezcurra mais aussi al., 2017 ).

The new squamosal bears about three process, an anterior techniques, a beneficial posterodorsal techniques, and you may a great posteroventral techniques. The fresh mediolaterally thin anterior process is the largest of one’s around three and you can articulates ventrally for the quadratojugal, variations a small part of the posterodorsal margin of lateral temporal fenestra, and you can articulates dorsally towards posteroventral side of this new postorbital. A horizontal ridge toward dorsal portion of the squamosal bounds the fresh new supratemporal fenestra sideways and you will goes on anteriorly onto the dorsolateral margin of your postorbital. A small anteriorly pointing top of the prior process of the new squamosal underlies a great posterodorsal projecting prong of your own dorsal procedure for brand new jugal. It contact excludes the fresh postorbital regarding contribution in the margin from the new infratemporal fenestra as mentioned previously, much like the condition in P. kirkpatricki (Weinbaum, 2011 ), and differing regarding symptom in aetosaurs (elizabeth.g., P. andressorum, Schoch & Desojo, 2016 ). A small position to your anteroventral facial skin of one’s anterior procedure fits a slimmer dorsal procedure for the newest quadratojugal.

This new rear portion of the squamosal stretches posterior toward head of the quadrate and you will divides into a great posteroventral and you can a keen anterodorsal techniques. The head of your quadrate fits on a distinct ventrally up against fossa one offers onto the prior part of the posteroventral process (Shape 4v); hence, the new posteroventral process and the horizontal side of the fresh articulation surface hides your mind of your quadrate out of lateral look at. Simultaneously, toward posteroventral osal, there is certainly a flat, posteriorly up against shelf one to allows the newest narrow anterodorsal margin of your own quadrate. The fresh new posterior skin of your posteroventral processes possess a small part you to definitely articulates towards paroccipital procedure for the brand new opisthotic (Figure 4v). Unlike very archosauriforms, this facet are thickened mediolaterally and you may circular toward a knob comparable into the condition in T. dabanensis (IVPP V3237) and aetosaurs (Nesbitt, 2011 ). The new posterodorsal processes contains a slit with the the rear edge you to definitely suits the newest posterolateral procedure for the brand new parietal.

Among skeleton of the palate, the vomers aren’t acknowledged of any known sample. not, the newest ectopterygoid, pterygoid, and palatine are kept when you look at the PEFO 34561 and you may an extra ectopterygoid is well known (PEFO 33857); the palate is finished but obscured inside PEFO 34089 (Contour three-dimensional).

5.2.14 Pterygoid

Whether or not none are entirely preserved (Shape 5a), the fresh new pterygoid consists of the newest anterior process, lateral techniques, and you may posterior processes. The new anterior procedure are triangular in the cross-area with a taller dorsal ridge one delineates the brand new feature from the the new midline. The new ventral epidermis for the procedure is actually concave. They tapers anteriorly nevertheless the connection with the brand new palatine try unfamiliar. The latest horizontal procedure include a beneficial posteriorly pointed side that slopes posteroventrally. The new lateral portion of the ventral epidermis features a huge element along side entire amount of the newest lateral procedure that articulates which have the new dorsal epidermis of the ectopterygoid (Profile 5a). The new pterygoid body’s a slimmer, vertically created blade. The brand new ventral facial skin holds a circular anteroposteriorly dependent ridge one continues on onto the prior procedure. Pterygoid white teeth is missing. The fresh new posterior procedure (= quadrate procedure) try broken in all specimens (elizabeth.g., PEFO 34561) rear into articulation area towards semi-circular fossa on basipterygoid means of the new parabasisphenoid. The newest anteroposterior length of the newest pterygoid is like one inside the archosauriforms including Erythrosuchus africanus (Gower chatspin apk hile, 2003 ) and you will P. kirkpatricki (TTU P-9000), instead of the anteroposteriorly abbreviated pterygoids out of aetosaurs (e.grams., L. meadei, TMM 31185-98; Neoaetosauroides engaeus, PVL 5698).

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