New L-molded quadratojugal is included laterally of the a great rugose trend like regarding brand new squamosal and you will jugal (Figure 4o)

5.dos.ten Quadratojugal

A small ridge into the posterodorsal margin of your own dorsal process articulates inside the a slot toward anteroventral osal. Rear to that there’s a low fossa that is overlapped because of the anterolateral edge of the fresh new quadrate. Brand new ventral suggestion of fossa is the anterior border out of the brand new quadrate foramen. This new posteroventral area of one’s quadratojugal forms a continuing surface which have the newest lateral portion of the quadrate, installing towards a good fossa to the lateral margin of your own second element. The brand new quadratojugal variations the fresh new posteroventral spot of one’s horizontal temporary fenestra from inside the Roentgen. callenderi.

Anteriorly, the fresh new tapered rear process of the fresh new jugal inserts to your a great triangular slot towards the horizontal surface of your quadratojugal (Profile 4o). This form of articulation is additionally within P. kirkpatricki (TTU P-9002; Weinbaum, 2011 : fig. 13). A similar articulation concept takes place in An excellent. ferratus and Paratypothorax andressorum (SMNS 19003; Schoch & Desojo, 2016 ), where a sandwich-triangular posterior procedure for the fresh new jugal inserts on an enthusiastic embayment into the the new anteroventral margin of the quadratojugal ventral to the horizontal temporal fenestra. On these taxa, a small anteroventral procedure for the fresh quadratojugal underlaps brand new jugal (Schoch, 2007 ). A similar articulation and additionally takes place in the fresh doswelliid archosauriform Rugarhychos sixmilensis (Wynd ainsi que al., 2020 ) recommending so it profile condition is generally plesiomorphic.

5.dos.eleven Postorbital

The new postorbital are a triradiate bones that have a keen ornamented horizontal epidermis and around three distinctive line of procedure (Figures 4q, r). The fresh new anterodorsal procedure have a distinct lateral slot you to receives the ventral and rear part of the postfrontal, brand new posterodorsal processes articulates into the anterodorsal osal, therefore the ventral processes fits into the a slot towards prior and you will medial surface of one’s posterodorsal process of the latest jugal. The fresh new dorsal margin are generally curved and possesses a distinct ridge one to variations the fresh anterolateral margin of your supratemporal fenestra. The new curved anterior margin features a weaker ridge, creating the new posterodorsal margin of your orbit. Brand new solid dorsal ridge, which offers posteriorly onto the squamosal, is not utilized in aetosaurs (e.grams., Desmatosuchus smalli, TTU P9024-; T. coccinarum, PEFO 38001). It can be probably absent in the A good. geoffreyi (UCMP 156046), hence bookofmatches nedir doesn’t preserve the fresh new postorbital, however, does have the new squamosal and you will does not have so it ridge. D. grallator has a comparable dorsal ridge on postorbital and squamosal (Sues et al., 2003 ).

New anteroventral portion of the squamosal and you may posterodorsal procedure for the brand new jugal nearly fits along the posteroventral edge of new postorbital, almost leaving out which element off participation from the horizontal temporary fenestra (Figure 3b). This near exemption isn’t novel so you can Roentgen. callenderi because also takes place in P. kirkpatricki (Weinbaum, 2011 ), and contribution is quite minimal from inside the aetosaurs (elizabeth.g., Good. ferratus) together with crocodylomorph D. grallator (Nesbitt, 2011 ; Schoch, 2007 ).

New triangular ability in the first place interpreted as lacrimal from the Parker mais aussi al. ( 2005 : fig. 2) is actually an isolated postorbital recovered to the head off PEFO 33787. Brand new anterior portion of the left squamosal from inside the Parker mais aussi al. ( 2005 : fig. 2b) is actually a keen articulated postorbital.

5.2.12 Quadrate

The newest quadrate try managed from inside the PEFO 34561 (Shape 4s, t), therefore the quadrates was blurred from inside the PEFO 38609 (Data 3c, d). The new quadrate body is a stronger, dorsoventrally tall bones that does not have fenestration and you may mountains posteroventrally, differing on symptom in shuvosaurids and you can aetosaurs where in actuality the quadrate slopes anteroventrally (Nesbitt, 2007 ).

A deep dorsoventrally situated fossa exists posterolateral with the lateral flange (Profile 4s). The pterygoid flange isn’t better-kept into the PEFO 34561, nevertheless the thickened root of the flange happens on the right ability only dorsal for the medial condyle along the medial boundary of quadrate.