callenderi attempt, whose mid-diaphysis significant axis diameter range out of fourteen.4 (PEFO 34561) so you’re able to twenty-two.step one mm (PEFO 33991). 1, that is following next brand new suggest (sixteen.4 mm) and you can similar to the median proportions (fifteen.cuatro mm) of the sample. Regardless if dimensions are perhaps not the ultimate proxy for ontogeny (Griffin et al., 2020 ), the existence of drastically big femora (PEFO 33991 and you may 35318) in addition to decreased an EFS into the PEFO 33843 each other suggest that second individual was not adult, although it had most likely enacted the purpose of inflection within the progress bend. Thus, we are able to hypothesize that every of your specimens contained in this analysis is actually neither very early juveniles or grownups away from an excellent skeletal readiness position.
5.9.2 Paramedian osteoderms
From inside the evaluating the fresh osteohistology of sampled paramedian osteoderms regarding Roentgen. callenderi and Krzyzanowskisaurus hunti, it is vital to remember that particular seen version may be because of positional outcomes, both in regards to the new osteoderm’s exact venue about carapace and you can in which along the osteoderm brand new histological area is actually taken. Lower than, we identify both osteoderms together with her, explicitly noting where they disagree.
Including the femur, the new sampled paramedian osteoderm out-of Roentgen. callenderi (PEFO 33940a) keeps a thin coating out-of sparry calcite (Rates 13f, i), whereas brand new osteoderm from K. hunti (UCMP 175058) have a level off emerald-coloured adhesive, perhaps shellac (Numbers 13h, j). Splits and you may inner spaces regarding both facets are permineralized because of the calcite spar. Short areas off UCMP 175058 is actually permineralized from the a keen opaque yellow-brownish mineral (Figures 13h, j), most likely an iron nutrient such as for instance siderite otherwise hematite. Each other specimens monitor a few high breaks that have displacement and you will better quantity of reduced hairline cracks (Data 13e–j) but they are if not well-maintained.
The evidence out-of reducing development, but no EFS, was generally consistent with the proportions selection of femora in the PEFO Roentgen
Both osteoderms are mostly lightweight cortical limbs with a fairly brief number of moderately size of vascular spaces (Numbers 13f–j); this type of places is actually smaller than those individuals found in the new aetosauriform An effective. geoffreyi ( : fig. 8), however, bigger as compared to heavily-manufactured short places that comprise interior cancellous structure inside the aetosaurs (Cerda mais aussi al., 2018 ; Cerda & Desojo, 2011 ; Parker ainsi que al., 2008 ; Scheyer et al., 2014 ). As noticed by Scheyer ainsi que al. ( 2014 : pg. 255) to own a tiny paramedian osteoderm off Roentgen. callenderi, this type of endosteal room try rimmed of the supplementary lamellar tissue; the latest additional muscle answering such places is far https://datingranking.net/tr/buddygays-inceleme more comprehensive about osteoderm from K. hunti (Figures 13h, j). Regarding specimen out-of K. hunti, new ventral border of the refurbished zone forms a marked discontinuity within second tissues and you will top tissue of the basal cortex (gray arrow in Contour 13j) that’s just as the resorption range Cerda ainsi que al. ( 2018 ) demonstrated to possess aetosaurs, however, it line try quicker type of for the Roentgen. callenderi (Shape 13i). On the other hand, new basal cortex in specimens is close to entirely avascular, conserve for most generally spread simple rivers and you may pri ) seen for Revueltosaurus in addition to condition in Good. geoffreyi ( ), whereas aetosaurs seem to be somewhat so much more vascular in this region (Cerda et al., 2018 ; Scheyer ainsi que al., 2014 ). So it top bones of one’s basal cortex constitutes synchronous-fibered muscle, however, does not have the fresh laminar structure described having Good. geoffreyi (cf. , p. 16). The fresh new basal cortex of your own Roentgen. callenderi osteoderm and has now relatively abundant Sharpey’s fabric within a leading direction to the enough time axis of cross-area (Profile 13i, just like the updates noticed in some aetosaurs (cf. Cerda mais aussi al., 2018 : fig. 7g–h), whereas they look getting missing inside K. hunti (Shape 13j).
