An excellent prearticular and you will coronoid have not been retrieved to own Roentgen

An excellent prearticular and you will coronoid have not been retrieved to own Roentgen

5.step three Mandible

Nearly the whole mandible is portrayed from inside the PEFO 34561 (Data 5d–j) and you can PEFO 38609 (Figure three dimensional), and additionally each other articulars, angulars, surangulars, splenials, and you will dentaries. callenderi.

5.step 3.step 1 Dentary

Over dentaries exists inside the PEFO 34561 (Contour 5d). Pearly whites occur to the anteriormost margin including the plesiomorphic reputation into the archosaurs and as opposed to this new edentulous margin within the aetosaurs. Brand new dentary enamel amount may differ anywhere between 10 and eleven. The brand new mesial-extremely alveoli feel the littlest diameter throughout the element as they are slightly constricted labiolingually; brand new alveolar diameters generally improve distally. For the dorsal see and you can undertaking mesially, the fresh new tooth row shape medially which makes it lingual of the fresh new horizontal wall of dentary. Enamel origins was opened predominantly into the lingual side of the mandible and you may interdental dishes occur. At the very least regarding best dentary of PEFO 34561, speaking of bonded in the mesial alveoli.

Anteriorly brand new dentary tapers so you can a rounded part of lateral view (Shape 5d). New weakly put up dentary symphysis variations a bent “jaw,” therefore the ventral margin of your dentary is actually generally game near the new symphysis; it will become a better line way more posteriorly. Quick foramina cover new horizontal facial skin of anterior section, that reduced total of count posteriorly. A row of such higher foramina takes place close and you may parallel so you can the new dorsal margin; it is hard to determine even if they have an excellent one-to-you to connection with the latest alveoli.

The new medial epidermis was excavated by the good Meckelian groove you to definitely runs to own most of along the element (Figure 5d). The new groove try tallest and you may strongest posteriorly, where it covers practically the complete medial side of the dentary, and you may constricts anteriorly, become a low groove around new 6th dentary enamel and following entirely disappears at the 3rd or last alveolus.

Posteriorly, three collection of tapering techniques stretch outside the rear margin of the enamel line (Figure 5d). The main and you may dorsalmost techniques articulate having type of grooves on anterolateral epidermis of the surangular, whereas the low process suits with the an effective groove to the anterolateral body of one’s angular. The essential dorsal and you will central procedure class an enthusiastic anteriorly tapering sulcus on the horizontal surface of your own dentary you to kept the brand new main anterior process towards the surangular (discover less than). The greater amount of dorsal processes features one or two preferred evident ridges on the horizontal epidermis; the brand new dorsalmost you’re continuing that have a lateral ridge to the surangular (pick less than). The latest main process talks about all or the city where the new outside mandibular fenestra was situated in other archosaurs; ergo, brand new additional mandibular fenestra are smaller than average takes place ventral into the main processes.

5.step three.2 Surangular

This new surangular models new dorsal the main lateral wall surface out of the new hemimandible, and you may good rugose ornamentation talks about the new lateral facial skin (Figure 5e). A-sharp ridge runs anteroposteriorly across the dorsolateral side of the lateral facial skin (= surangular ridge) of your own surangular such as many other archosaurs, and phytosaurs, P. kirkpatricki, A. babbitti, and you will B. kupferzellensis (Gower, 1999 ; Nesbitt, 2005a , 2005b ; Stocker, 2012 ; Weinbaum, 2011 ).

The latest anterior edge of new surangular possess around three prior projections (Figure 5e). This new central projection ‘s the biggest and you will matches horizontal in order to an anteriorly tapering sulcus within dorsal and you can central rear process for the the latest dentary (see above). A deep concavity between the dorsal and main process of your own surangular retains the latest dorsal rear projection towards dentary. The greater ventral prior procedure of the new surangular is determined further posteriorly along side ventral side of the latest feature and also a beneficial narrow ventral flange that will have been secured sideways because of the angular.