An excellent prearticular and you will coronoid haven’t been recovered to own Roentgen

An excellent prearticular and you will coronoid haven’t been recovered to own Roentgen

5.3 Mandible

Nearly the entire mandible was depicted within the PEFO 34561 (Figures 5d–j) and you can PEFO 38609 (Profile three dimensional), plus one another articulars, angulars, surangulars, splenials, and you may dentaries. callenderi.

5.step three.step one Dentary

Over dentaries are present within the PEFO 34561 (Shape 5d). Teeth exist into the anteriormost margin such as the plesiomorphic updates within the archosaurs and you will instead of brand new edentulous margin from inside the aetosaurs. This new dentary tooth number may differ ranging from 10 and you will 11. The latest mesial-most alveoli have the minuscule diameter in the ability and are also a bit limited labiolingually; the fresh alveolar diameters essentially raise distally. During the dorsal check and undertaking mesially, new enamel line contours medially so that it is lingual regarding this new horizontal wall of one’s dentary. Enamel sources is actually exposed mainly with the lingual side of the mandible and you can interdental dishes can be found. No less than regarding best dentary off PEFO 34561, these are fused on mesial alveoli.

Anteriorly the new dentary tapers in order to a curved point in horizontal have a look at (Contour 5d). The fresh weakly install dentary symphysis variations a bent “mouth,” in addition to ventral margin of your dentary are broadly game close the fresh new symphysis; it gets a clearer boundary far more posteriorly. Quick foramina defense the lateral skin of your prior section, and these decrease in count posteriorly. A-row out of such as highest foramina happen close and you may parallel to help you the fresh dorsal margin; it is hard to determine even if they have already an effective one-to-you to definitely connection with the latest alveoli.

The fresh medial skin try excavated because of the a Meckelian groove you to definitely offers getting much of the size of the brand new element (Profile 5d). The brand new groove is actually highest and you may greatest posteriorly, where it talks about almost the entire medial section of the dentary, and you will constricts anteriorly, are a low groove at about the 6th dentary tooth and up coming totally vanishes from the 3rd or next alveolus.

Posteriorly, three line of tapering procedure continue beyond the rear margin of your enamel row (Profile 5d). The latest central and you can dorsalmost process articulate with type of grooves on anterolateral epidermis of your surangular, while the low processes matches into an excellent groove into the anterolateral facial skin of angular. By far the most dorsal and central procedure bracket an enthusiastic anteriorly tapering sulcus to the horizontal surface of your dentary one to held brand new main anterior techniques on the surangular (get a hold of less than). The greater number of dorsal techniques have several popular evident ridges for the lateral facial skin; this new dorsalmost you’re persisted having a lateral ridge towards surangular (come across lower than). The newest central techniques talks about the otherwise all area in which the new exterior mandibular fenestra would be situated in most other archosaurs; hence, new external mandibular fenestra is smaller than average occurs ventral into the central procedure.

5.step three.2 Surangular

The newest surangular versions the dorsal area of the lateral wall structure of the fresh new hemimandible, and you will a rugose ornamentation talks about the brand new horizontal surface (Contour 5e). A-sharp ridge stretches anteroposteriorly across the dorsolateral side of the latest lateral skin (= surangular ridge) of your own surangular as with a great many other archosaurs, including phytosaurs, P. kirkpatricki, A good. babbitti, and you may B. kupferzellensis (Gower, 1999 ; Nesbitt, 2005a , 2005b ; Stocker, 2012 ; Weinbaum, 2011 ).

New prior side of this new surangular has around three anterior forecasts (Figure 5e). The brand new central projection is the largest and you may matches horizontal so you’re able to an enthusiastic anteriorly tapering sulcus amongst the dorsal and main posterior processes into the dentary (pick more than). An intense concavity involving the dorsal and you may main procedure of your own surangular keeps new dorsal rear projection with the dentary. The more ventral anterior process of the fresh new surangular is determined next posteriorly along the ventral edge of the fresh new element features a good thin ventral flange that may had been safeguarded laterally by the angular.