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5.8.step one Prior cervical paramedian osteoderms
The original about three paramedian rows of the right side is maintained inside PEFO 34561, and some rows try kept into the PEFO 42442/UWBM 116869 (Figure 12h). The initial osteoderm is roughly triangular within the dorsolateral take a look at that have straight medial and you can posterior entation is actually weakly incised, and there’s zero anterior pub. Instead, for the prior ventral body there is certainly a great scalloped, rugose facial skin to own articulation to your rear margin of one’s head. So it osteoderm is much like the initial within the morphology except it lacks the fresh ventral articular skin and you may rather enjoys an effective weak anterior bar along the narrow prior margin. The 3rd osteoderm try square (mediolateral depth:anteroposterior size proportion of dos.0), with a beneficial dorsal ornamentation from short pits. This osteoderm was curved near its lateral border, and there is a pronounced anterior club which have good triangular anterior projection at the part out-of arching. The ventral epidermis of one’s plate are smooth. Inside the dorsal examine, the fresh new medial margin try straight, while brand new horizontal margin try carefully circular and you may does not have a keen articular body for a horizontal osteoderm.
5.8.dos Middle and you may posterior cervical paramedian osteoderms
Cervical paramedian osteoderms was broad than just long (mediolateral depth:anteroposterior size ratio regarding dos.5 leaving out the brand new anterior bar) and appear so you can expand quite during the for every subsequent rear row (Figure 12h). The fresh dorsal pitting was smaller and you may weakly incised. The fresh new prior bar makes up about that-5th of the overall period of the newest osteoderm. The new prior margin of osteoderm try straight and you can lacks anteromedial and you can anterior forecasts. This new osteoderm try slightly curved nearby the lateral edge, two-thirds the exact distance regarding medial line. There is absolutely no dorsal eminence from the area in which the osteoderm was arched. When you look at the dorsal view the medial margin of one’s osteoderm was straight, whereas new lateral line are weakly rounded. This new horizontal margins taper and have no signs of a keen articular body getting a lateral osteoderm. Therefore, discover at this time zero research having cervical horizontal osteoderms for the R. callenderi.
5.8.step three Dorsal trunk paramedian osteoderms
Dorsal paramedian osteoderms try called such as for instance as they safeguards the trunk spine series (Long & Ballew, 1985 ). These types of osteoderms (Figures 12a, b, h) keeps mediolateral depth:anteroposterior size rates of around 2.dos leaving out the fresh new anterior club. The dorsal pitting on these plates are huge and more incised after that into the cervical paramedians. Within the dorsal look at, the fresh new medial margin is actually straight, in addition to lateral boundary some circular. Like in the newest cervicals, these osteoderms is actually transversely arched around the horizontal margin; but not, in many of those osteoderms there’s a great dorsal eminence when you look at the the type of an enthusiastic anteroposterior ridge you to does not have pitting and relationships brand new posterior margin of one’s osteoderm. It ridge is more obvious about even more posteriorly situated osteoderms, although right updates with the transform isn’t obvious into the the current materials. The latest prior pub try well-set up however, comprises lower than one to-fifth of the complete length of new osteoderm, compared to the newest cervical osteoderms. Additionally, there’s two type of processes into the anterior bar, a good triangular anterior processes anterior towards dorsal eminence and an excellent triangular anteromedial projection. The latest anterior margin of the osteoderm anywhere between both of these projections are concave within the dorsal view. Equivalent forecasts in addition to concave edian dishes regarding non-desmatosuchin aetosaurs (age.grams., Scutarx deltatylus, PEFO 34045). The brand new ventral facial skin of osteoderm is smooth.
5.8.4 Horizontal trunk osteoderms
The brand new articulated sample PEFO 42442/UWBM 116869 (Profile 12h) conserves a few of the horizontal osteoderms during the articulation (seven to the right side and you will six on leftover), and additionally they have been present through at the least the newest middle-trunk to help you sacral urban area. Cervical and you will caudal lateral osteoderms are not preserved. There clearly was merely just one set of horizontal osteoderms for every row such as aetosaurs, different away from A good. geoffreyi, that certain places has actually type of external and internal lateral osteoderms ( ). New horizontal osteoderms away from R. callenderi was markedly oblong (subrectangular or oval, more than greater), that have an elevated main keel and an adjoining ornamentation regarding shallow pits like in one other osteoderms (Shape 12c). There’s no strong medial articulation skin for the associated paramedian; not, the latest medial edge is straight, while the brand new horizontal line try circular. The fresh horizontal osteoderms try some flexed from inside the prior and you may posterior views, ergo new feature is put into type of medial and you can horizontal flanges such as aetosaurs (Parker, 2007 ). This type of flanges is off approximately equal proportions, and you may total the fresh osteoderms are narrow in comparison with almost every other aetosauriforms, different notably regarding the lateral osteoderms off An excellent. geoffreyi, and aetosaurs that are far wide in dorsal examine and you will either rectangular or greater than simply enough time rectangles (Desojo et al. Web baДџlantД±sД±, 2013 ; ). Also, the new laterals away from Roentgen. callenderi run out of obvious dorsal eminences one mode elongate spines in a lot of most other aetosauriforms (age.g, desmatosuchin aetosaurs sensu Parker, 2016a ). Alternatively they look more like the latest appendicular osteoderms found in aetosaurs and erpetosuchids (elizabeth.grams., Ezcurra ainsi que al., 2017 ; Heckert & Lucas, 1999 ).