The best-preserved tibia is a remote leftover element throughout the PFV 297 (PEFO 34273; Numbers 10l–o)

The best-preserved tibia is a remote leftover element throughout the PFV 297 (PEFO 34273; Numbers 10l–o)

5.eight.12 Tibia

The newest proximal direct of tibia is much longer similarly to aetosaurs; Parrish ( 1986 ) suggested your lengthened tibial head could be a beneficial synapomorphy out of this new aetosaurs. Eg aetosaur tibiae, the fresh proximal facial skin of tibia within the R. callenderi are divided by the a ridge into the a couple of equal size of a little concave medial and horizontal condyles (Rates 10l–o). The fresh proximal surfaces of your medial and you clover dating giriЕџ will horizontal condyles was concave, and you will a definite lip is obtainable in which the one or two condyles meet. This new proximal head of the tibia is actually greatly extended mediolaterally relative to the diameter of your axle with the most useful expansion medially (Profile 10n). This new axle is subrounded within the cross-section. The latest tibia size is roughly a couple of-thirds the length of the latest femur (Study S2). A straight ridge is located to your posterolateral region of the shaft.

The fresh new distal avoid is even mediolaterally offered not once the highly as the proximal end and you can highly is comparable to brand new suchian condition (Profile 10o). Brand new medial portion of the articular surface ideas distally that’s convex. The latest horizontal part is actually less distally extended collectively the rear edge and you may an effective rear groove splits the two articulation counters.

5.7.13 Fibula

Into the PEFO 34561, the new fibula is fairly upright (Numbers 10p–s), varying out of compared to aetosaurians, with a noticable “kink” (e.g., N. engaeus; PVL 3525; L. meadei, TTM 31185-97). This new proximal prevent is anteroposteriorly prolonged and circular when you look at the proximal glance at. The tiny, rounded iliofibularis crest is based you to-third the length distally on the horizontal surface of one’s axle (Figure 10p). Its exterior surface is simple, barely raised above top of the shaft different on a great deal more obvious rugose crest used in aetosaurs (Parrish, 1986 ) which is significantly more distally organized. The latest distal end was mediolaterally compacted and you may stretched anteroposteriorly relative to the fresh new shaft. The fresh distal articular epidermis is simple and you will beveled anteromedially such as phytosaurs (e.grams., UCMP 122621).

5.seven.14 Astragalus

This new astragalus (Figures 11a–f) is similar to compared to other suchians (age.g., aetosaurs). During the prior have a look at, a massive prior empty takes up a lot of new prior surface (Shape 11a). The latest tibial and fibular surfaces fulfill during the a peak inside anterior view. Posteriorly, the brand new astragalar peg (Shape 11b) can be obtained into the posterodistal facial skin only ventral on the distolaterally popular rear groove. The brand new astragalar peg enjoys good mediolateral length from the double brand new anteroposterior height of the feature. The posterodistal skin of the peg possess a low office, but it office isn’t reflected because the a good ridge toward expressing surface of your own calcaneum. The new fibular aspect of the astragalus was concave and subrectangular (Contour 11e). New tibial articular factors (Figure 11c) are split up into two concave countries that have a little convex town splitting up a smaller lateral articular skin and you may a more impressive medial articular body. The bigger surface articulates with the ventral procedure for the fresh new tibia. Small articular facial skin can be found towards the whole dorsal facial skin of fibular processes. A slimmer ridge distinguishes the brand new tibial and fibular aspects. New distal roller was convex and you can is comparable to the ones from almost every other suchians (get a hold of Sereno, 1991 ; Nesbitt, 2011 ).

5.7.fifteen Calcaneum

The fresh new calcaneum (Figures 11g–l) is like most early suchians (elizabeth.grams., aetosaurs). The latest hemicylindrical articular surface try divided because of the an anteroposteriorly trending ridge into the fibular aspect and you will astragalar aspect. New astragalar part is totally medial for the fibular facet, in the place of the condition for the Elizabeth. okeeffeae (AMNH FR 30857), P. kirkpatricki (e.grams., TTU-P 9002), and you may crocodylomorphs (age.grams., “H. agilis” YPM 41198), where in fact the astragalar element is positioned even more ventrally (Nesbitt, 2011 ). The fresh new concave outlet toward astragalar peg (Profile 11h) cannot infiltrate brand new medial wall structure of your hemicylindrical articular body. The newest calcaneal tuber was led posteriorly like that away from several of very early suchians. The brand new calcaneal tuber try mediolaterally longer and you will offered dorsal and you can some in the ventral advice (Figure 11k). The latest tuber doesn’t always have an enthusiastic anteroposteriorly established groove as in P. kirkpatricki (elizabeth.grams., TTU P-9002) and you may crocodylomorphs (e.g., “H. agilis,” YPM 41198). Alternatively, this new rear skin was concave like in aetosaurs (elizabeth.g., Typothorax antiquum; Lucas mais aussi al., 2002 ). The new ventral epidermis bears a great concave fossa. The new articulation area to the distal tarsal cuatro is markedly concave and not flat as in phytosaurs or any other suchians (Long & Murry, 1995 ).

Trả lời

Email của bạn sẽ không được hiển thị công khai.