callenderi sample, whoever mid-diaphysis big axis diameter range regarding fourteen.cuatro (PEFO 34561) so you can twenty two.step one mm (PEFO 33991). step 1, that is below new indicate (sixteen.cuatro mm) and you may much like the average dimensions (15.4 mm) of one’s test. Even when dimensions are maybe not the ultimate proxy getting ontogeny (Griffin et al., 2020 ), the presence of dramatically larger femora (PEFO 33991 and you will 35318) and also the not enough an enthusiastic EFS within the PEFO 33843 one another indicate that second private was not fully grown, although it had likely introduced the purpose of inflection within the gains bend. Hence, we can hypothesize that of your specimens in this studies are neither very early juveniles or grownups out-of a great skeletal maturity position.
5.nine.2 Paramedian osteoderms
Into the researching the fresh new osteohistology of your tested paramedian osteoderms off Roentgen. callenderi and you will Krzyzanowskisaurus hunti, it is essential to note that specific seen type is generally because of positional effects, in regards to the brand new osteoderm’s appropriate place regarding carapace and you will in which across the osteoderm the histological part is removed. Below, we define the 2 osteoderms together, clearly noting where it disagree.
Including the femur, the latest tested paramedian https://datingranking.net/tr/beautifulpeople-inceleme/ osteoderm off Roentgen. callenderi (PEFO 33940a) has a thinner layer regarding sparry calcite (Figures 13f, i), whereas the newest osteoderm off K. hunti (UCMP 175058) provides a layer away from amber-coloured adhesive, perhaps shellac (Figures 13h, j). Cracks and inner spaces of one another issues was permineralized by calcite spar. Short zones of UCMP 175058 is actually permineralized from the a keen opaque purple-brown nutrient (Figures 13h, j), probably a metal nutrient including siderite otherwise hematite. One another specimens monitor a number of large breaks with displacement and you may better number of reduced hairline splits (Data 13e–j) but are if you don’t well-managed.
Evidence out of slowing gains, however, zero EFS, is actually generally consistent with the proportions set of femora in the PEFO Roentgen
One another osteoderms is mainly compact cortical limbs that have a somewhat small quantity of meagerly size of vascular areas (Figures 13f–j); this type of places was smaller than those found in the aetosauriform An excellent. geoffreyi ( : fig. 8), but much bigger compared to the heavily-packed quick spaces that define inner cancellous structure within the aetosaurs (Cerda mais aussi al., 2018 ; Cerda & Desojo, 2011 ; Parker mais aussi al., 2008 ; Scheyer et al., 2014 ). Since the noticed because of the Scheyer mais aussi al. ( 2014 : pg. 255) to own a little paramedian osteoderm off Roentgen. callenderi, these types of endosteal rooms is actually rimmed because of the additional lamellar cells; the second cells filling up these spaces is far more detailed about osteoderm out-of K. hunti (Numbers 13h, j). Regarding the specimen regarding K. hunti, the newest ventral boundary in the remodeled zone forms reasonable discontinuity within secondary tissues and you will number 1 tissues of basal cortex (grey arrow during the Profile 13j) that’s much like the resorption line Cerda et al. ( 2018 ) demonstrated to possess aetosaurs, but that it line try less line of inside R. callenderi (Shape 13i). Alternatively, the basal cortex both in specimens is close to entirely avascular, conserve for some extensively separated effortless streams and you may pri ) noticed getting Revueltosaurus and the symptom in A good. geoffreyi ( ), while aetosaurs appear to be quite a whole lot more vascular of this type (Cerda mais aussi al., 2018 ; Scheyer et al., 2014 ). It number one limbs of one’s basal cortex constitutes synchronous-fibered structure, but lacks the brand new laminar surface revealed to possess A great. geoffreyi (cf. , p. 16). The newest basal cortex of your R. callenderi osteoderm and contains apparently plentiful Sharpey’s materials within a premier angle on long axis of get across-point (Profile 13i, similar to the standing present in certain aetosaurs (cf. Cerda ainsi que al., 2018 : fig. 7g–h), whereas they look is absent from inside the K. hunti (Contour 13j).