The fresh new tested femur (PEFO 33843) have a diameter off fifteen

callenderi decide to try, whoever middle-diaphysis major axis diameter selections from 14.cuatro (PEFO 34561) to help you twenty-two.1 mm (PEFO 33991). 1, that is below the newest imply (16.cuatro mm) and you will just like the median size (15.4 mm) of one’s attempt. Even when size is not the best proxy to have ontogeny (Griffin ainsi que al., 2020 ), the current presence of drastically larger femora (PEFO 33991 and you can 35318) and insufficient a keen EFS when you look at the PEFO 33843 one another imply that second personal wasn’t adult, though it had more than likely introduced the point of inflection in its progress bend. Thus, we are able to hypothesize that most of specimens within research was none early juveniles or people out-of a skeletal maturity angle.

5.9.2 Paramedian osteoderms

In the evaluating the fresh new osteohistology of your own tested paramedian osteoderms of Roentgen. callenderi and Krzyzanowskisaurus hunti, it’s important to remember that particular seen type can be due to positional effects, both in terms of new osteoderm’s perfect place throughout the carapace and in which along side osteoderm the latest histological part is actually taken. Lower than, i describe the 2 osteoderms along with her, explicitly noting where they differ.

For instance the femur, brand new tested paramedian osteoderm regarding R. callenderi (PEFO 33940a) possess a finer level from sparry calcite (Rates 13f, i), while the osteoderm regarding K. hunti (UCMP 175058) features a layer away from amber-coloured adhesive, perhaps shellac (Numbers 13h, j). Fractures and you will inner spaces away from each other points is actually permineralized by the calcite spar. Small zones out-of UCMP 175058 are permineralized of the an opaque red-colored-brownish mineral (Numbers 13h, j), probably an iron mineral eg siderite otherwise hematite. Each other specimens display a number of large cracks with displacement and you will higher quantity of faster hairline fractures (Data 13e–j) but are if not well-managed.

The data out of slowing progress, however, zero EFS, is broadly consistent with the proportions listing of femora on the PEFO Roentgen

One another osteoderms was mainly compact cortical limbs which have a fairly quick quantity of sparingly size of vascular areas (Figures 13f–j); such places was smaller than those found in the fresh aetosauriform Good. geoffreyi ( : fig. 8), but much larger compared to densely-packed brief areas that define inner cancellous muscle for the aetosaurs (Cerda et al., 2018 ; Cerda & Desojo, 2011 ; Parker mais aussi al., 2008 ; Scheyer et al., 2014 ). Given that seen because of the Scheyer mais aussi al. ( 2014 : pg. 255) having a tiny paramedian osteoderm regarding Roentgen. callenderi, this type of endosteal places is rimmed because of the additional lamellar tissue; the fresh new additional muscle filling up these types of rooms is more thorough on the osteoderm out-of K. hunti (Numbers 13h, j). About specimen away from K. hunti, the fresh new ventral boundary on the refurbished zone models a marked discontinuity between your secondary structure and you can number one structure of your own basal cortex (grey arrow for the Profile 13j) that’s just as the resorption line Cerda ainsi que al. ( 2018 ) revealed getting aetosaurs, however, so it boundary is shorter distinct inside R. callenderi (Contour 13i). Conversely, the fresh basal cortex in both specimens is nearly entirely avascular, save yourself for some generally spread easy canals and you may pri ) noticed to own Revueltosaurus and the condition in An excellent. geoffreyi ( ), while aetosaurs appear to be quite a great deal more vascular here (Cerda mais aussi al., 2018 ; Scheyer ainsi que al., 2014 ). Which primary limbs of your own basal cortex comprises parallel-fibered structure, but does not have the fresh new laminar consistency revealed to possess A beneficial. geoffreyi (cf. , p. 16). The fresh new basal cortex of your own R. callenderi osteoderm and has now apparently numerous Sharpey’s fibers from the a top direction towards a lot of time axis of your own mix-point (Profile 13i, similar to the updates noticed in specific aetosaurs (cf. Cerda mais aussi al., 2018 : fig. 7g–h), whereas they appear becoming absent from inside the K. hunti (Shape 13j).

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