5.8.1 Anterior cervical paramedian osteoderms
The original about three paramedian rows of your right side try maintained for the PEFO 34561, and several rows is actually preserved inside the PEFO 42442/UWBM 116869 (Contour 12h). The original osteoderm is approximately triangular in dorsolateral evaluate which have upright medial and you will posterior entation was weakly incised, and there is zero anterior club. Instead, to your prior ventral surface you will find a beneficial scalloped, rugose epidermis to have articulation on posterior margin of your own skull. That it osteoderm is similar to the initial within the morphology except so it lacks the latest ventral articular facial skin and you will rather provides a weak anterior pub across the thin prior margin. The 3rd osteoderm was square (mediolateral width:anteroposterior size proportion regarding 2.0), with a dorsal ornamentation off brief pits. It osteoderm was curved close their horizontal border, as there are a noticable prior pub with an effective triangular prior projection at point away from arching. The ventral epidermis of your own plate is actually easy. During the dorsal view, the newest medial margin are straight, whereas new lateral margin was lightly game and you can lacks an articular facial skin having a horizontal osteoderm.
5.8.dos Center and you can rear cervical paramedian osteoderms
Cervical paramedian osteoderms was broad than simply a lot of time (mediolateral thickness:anteroposterior length ratio regarding 2.5 excluding brand new anterior pub) and look so you’re able to widen a little for the for each and every next posterior line (Profile 12h). Brand new dorsal pitting are reduced and weakly incised. The fresh anterior pub makes up about one-5th of one’s full length of this new osteoderm. New anterior margin of one’s osteoderm is actually straight and you can lacks anteromedial and prior projections. The osteoderm is slightly curved around the lateral border, two-thirds the exact distance on the medial line. There is absolutely no dorsal eminence of this part in which the osteoderm is curved. In the dorsal look at the medial margin of your osteoderm is upright, while brand new horizontal edge is weakly curved. New horizontal margins taper and have now zero signs and symptoms of an articular facial skin getting a lateral osteoderm. For this reason, there is presently no evidence to possess cervical lateral osteoderms in the R. callenderi.
5.8.step three Dorsal trunk area paramedian osteoderms
Dorsal paramedian osteoderms is termed such as for example as they safety the trunk vertebral show (Enough time & Ballew, 1985 ). Such osteoderms (Figures 12a, b, h) features mediolateral depth:anteroposterior duration percentages of about dos.2 leaving out the latest prior bar. Brand new dorsal pitting in these plates is actually larger plus incised next for the cervical paramedians. From inside the dorsal see, brand new medial margin is actually straight, therefore the horizontal boundary slightly round. Such as brand new cervicals, these types of osteoderms is transversely curved around the horizontal margin; but not, in a lot of of these osteoderms there is a good dorsal eminence inside the the form of a keen anteroposterior ridge that lacks pitting and connections the newest posterior margin of your osteoderm. This ridge is more pronounced regarding the a lot more posteriorly centered osteoderms, nevertheless the appropriate condition from the transform is not obvious into the the existing content. The fresh anterior club are well-build however, comprises lower than that-5th of overall duration of the latest osteoderm, compared with the new cervical osteoderms. Furthermore, there are two distinct processes to your anterior club, an excellent triangular anterior processes anterior towards dorsal eminence and you may a great triangular anteromedial projection. The fresh anterior margin of one’s osteoderm between these forecasts is actually concave into the dorsal consider. Comparable forecasts and also the concave edian plates out-of low-desmatosuchin aetosaurs (e.g., Scutarx deltatylus, PEFO 34045). The brand new ventral surface of the osteoderm is effortless.
5.8.cuatro Horizontal trunk osteoderms
New articulated sample PEFO 42442/UWBM 116869 (Profile 12h) saves a number of the horizontal osteoderms inside the asiandating indir articulation (7 off to the right front and you will half a dozen into the remaining), and so they was in fact expose courtesy no less than the newest mid-trunk area to help you sacral area. Cervical and caudal lateral osteoderms are not maintained. There is just an individual number of lateral osteoderms per row like in aetosaurs, differing of A great. geoffreyi, which in particular places has actually collection of internal and external lateral osteoderms ( ). The new lateral osteoderms out of Roentgen. callenderi is significantly oblong (subrectangular otherwise egg-shaped, more than large), which have an increasing central keel and you may a surrounding ornamentation out of superficial pits as with one other osteoderms (Shape 12c). There is absolutely no strong medial articulation epidermis towards corresponding paramedian; yet not, this new medial edge is straight, whereas the latest lateral line is actually game. The new lateral osteoderms is some flexed from inside the prior and you may posterior views, therefore the brand new element are split into line of medial and you will horizontal flanges as in aetosaurs (Parker, 2007 ). These flanges is off around equivalent proportions, and you will overall this new osteoderms have become slim when comparing to most other aetosauriforms, different somewhat regarding lateral osteoderms out of An excellent. geoffreyi, and aetosaurs that are far wide during the dorsal consider and you may possibly square or large than simply long rectangles (Desojo ainsi que al., 2013 ; ). Also, the fresh laterals out of R. callenderi use up all your obvious dorsal eminences you to definitely setting elongate spines in lot of almost every other aetosauriforms (e.g, desmatosuchin aetosaurs sensu Parker, 2016a ). Alternatively they appear a lot more like the latest appendicular osteoderms used in aetosaurs and you can erpetosuchids (e.g., Ezcurra ainsi que al., 2017 ; Heckert & Lucas, 1999 ).
