5.3 Mandible
Nearly the whole mandible try represented inside the PEFO 34561 (Figures 5d–j) and PEFO 38609 (Profile 3d), along with both articulars, angulars, surangulars, splenials, and you can dentaries. callenderi.
5.step 3.1 Dentary
Over dentaries occur inside PEFO 34561 (Contour 5d). White teeth exist into the anteriormost margin such as the plesiomorphic updates inside archosaurs and in place of the latest edentulous margin during the aetosaurs. This new dentary tooth amount may vary anywhere between ten and you can eleven. The brand new mesial-very alveoli have the littlest diameter regarding the feature and generally are a little limited labiolingually; the latest alveolar diameters generally boost distally. Inside the dorsal evaluate and you can performing mesially, this new enamel row shape medially which makes it lingual from this new horizontal wall of the dentary. Enamel root try opened mostly for the lingual section of the mandible and you will interdental dishes exist. About about proper dentary away from PEFO 34561, speaking of fused from the mesial alveoli.
Anteriorly the fresh new dentary tapers in order to a circular point in horizontal take a look at (Figure 5d). The new weakly setup dentary symphysis models a rounded “chin,” together with ventral margin of the dentary is actually broadly round close this new symphysis; it gets a crisper boundary alot more posteriorly. Short foramina cover the newest horizontal surface of your own anterior section, and these reduced total of amount posteriorly. A row regarding such as for instance high foramina happen near and synchronous to help you the newest dorsal margin; it is difficult to determine though they have a one-to-one experience of the new alveoli.
The fresh new medial facial skin try excavated of the a good Meckelian groove you to definitely stretches having most of the length of the fresh function (Contour 321chat 5d). The fresh new groove are tallest and you will greatest posteriorly, in which they discusses very nearly the complete medial section of the dentary, and constricts anteriorly, become a shallow groove at about the latest 6th dentary enamel and you can up coming completely vanishes at the 3rd or last alveolus.
Posteriorly, around three collection of tapered procedure expand not in the posterior margin of the enamel line (Figure 5d). The fresh main and you can dorsalmost processes articulate with distinctive line of grooves to the anterolateral body of surangular, while the lower processes matches to your an excellent groove to your anterolateral facial skin of angular. One particular dorsal and you may main process class a keen anteriorly tapering sulcus for the lateral surface of one’s dentary one kept the fresh new central prior processes on surangular (find below). The greater dorsal process has actually several common clear ridges to the horizontal skin; the brand new dorsalmost one is carried on which have a horizontal ridge towards the surangular (discover lower than). The newest central processes talks about all or most of the city where the fresh new additional mandibular fenestra could be based in other archosaurs; thus, the newest external mandibular fenestra are small and happen ventral with the main techniques.
5.step 3.2 Surangular
The new surangular variations brand new dorsal a portion of the lateral wall structure of the brand new hemimandible, and good rugose ornamentation covers the newest horizontal epidermis (Contour 5e). A sharp ridge runs anteroposteriorly along the dorsolateral side of the fresh lateral facial skin (= surangular ridge) of your own surangular like in a number of other archosaurs, along with phytosaurs, P. kirkpatricki, A beneficial. babbitti, and you will B. kupferzellensis (Gower, 1999 ; Nesbitt, 2005a , 2005b ; Stocker, 2012 ; Weinbaum, 2011 ).
The fresh new anterior side of new surangular possess about three prior projections (Contour 5e). The newest main projection ‘s the largest and you may fits horizontal in order to an anteriorly tapered sulcus within dorsal and you may main rear techniques toward the dentary (see more than). An intense concavity between the dorsal and central techniques of your surangular retains the fresh dorsal posterior projection towards the dentary. More ventral anterior process of new surangular is determined then posteriorly across the ventral side of the new ability possesses a beneficial narrow ventral flange that can was in fact covered laterally of the angular.
