Re: [dinosaur] Mesenosaurus efremovi, new synapsid species from Oklahoma + Metoposaurus cranial sutures

A blog post:

New publication: A new varanopid synapsid from the early Permian of
Oklahoma and the evolutionary stasis in this clade (Maho, Gee, & Reisz,
Royal Society Open Science)

https://urldefense.proofpoint.com/v2/url?u=https-3A__bryangee.weebly.com_blog_new-2Dpublication-2Da-2Dnew-2Dvaranopid-2Dsynapsid-2Dfrom-2Dthe-2Dearly-2Dpermian-2Dof-2Doklahoma-2Dand-2Dthe-2Devolutionary-2Dstasis-2Din-2Dthis-2Dclade-2Dmaho-2Dgee-2Dreisz-2Droyal-2Dsociety-2Dopen-2Dscience&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=MORhjBItgTTa8p3pANXvuHRE2QE20jvLwrFiKKNnZoA&e= 

<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.avg.com_email-2Dsignature-3Futm-5Fmedium-3Demail-26utm-5Fsource-3Dlink-26utm-5Fcampaign-3Dsig-2Demail-26utm-5Fcontent-3Dwebmail&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=79-cA9WiYXURkXkprvmeQoeZypAMMAiFLNZEaW7cEAk&e= >
Virus-free.
www.avg.com
<https://urldefense.proofpoint.com/v2/url?u=http-3A__www.avg.com_email-2Dsignature-3Futm-5Fmedium-3Demail-26utm-5Fsource-3Dlink-26utm-5Fcampaign-3Dsig-2Demail-26utm-5Fcontent-3Dwebmail&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=79-cA9WiYXURkXkprvmeQoeZypAMMAiFLNZEaW7cEAk&e= >
<#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>

On Wed, Oct 23, 2019 at 6:46 AM Ben Creisler <[email protected]> wrote:

> Ben Creisler
> [email protected]
>
> New papers:
>
> Free pdf:
>
> Sigi Maho, Bryan M. Gee and Robert R. Reisz (2019)
> A new varanopid synapsid from the early Permian of Oklahoma and the
> evolutionary stasis in this clade.
> Royal Society Open Science 6(10): 191297
> doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1098_rsos.191297&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=tQ8Az_W8ZwSvJQ3psz0hp-HjweLhAEHbMBxTJns9FPE&e= 
> https://urldefense.proofpoint.com/v2/url?u=https-3A__royalsocietypublishing.org_doi_abs_10.1098_rsos.191297&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=_aCmVdVP75vDDWepkfsBdN5JRitSSZTXFm-PpJd9F7g&e= 
> Free pdf:
> https://urldefense.proofpoint.com/v2/url?u=https-3A__royalsocietypublishing.org_doi_pdf_10.1098_rsos.191297&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=6dqfFIkOAu3D5X7Wm2UBWiQ5mJoP_l1rJdnuSVhJwy0&e= 
>
>
> Varanopids are a basal clade of small- to medium-sized non-therapsid
> synapsids, whose range extends from the late Pennsylvanian to the late
> middle Permian, and are found in North America, Russia, Europe and South
> Africa. The greatest varanopid diversity is observed at the fossiliferous
> cave deposits near Richards Spur, Oklahoma, well known for the preservation
> of a complex early Permian upland community. Two previously described
> varanopids, Mycterosaurus and Varanops, are known only from fragmentary
> disarticulated material at Richards Spur. A third putative varanopid,
> Basicranodon fortsillensis, represented by a partial parasphenoid, has been
> synonymized with Mycterosaurus longiceps. This study reports on a new
> varanopid taxon, represented by substantially more complete material,
> including three nearly complete skulls. Such comprehensive cranial material
> allows for a detailed study of the taxon and its relationship to other
> varanopids. This new varanopid bears great morphological similarity to
> Mesenosaurus romeri from the middle Permian Mezen River Basin of northern
> Russia. Phylogenetic analysis recovers a sister relationship between this
> taxon and Me. romeri. This relationship, in conjunction with a detailed
> morphological comparison, supports the placement of this taxon within
> Mesenosaurus, as a new species, Me. efremovi. These results reveal an
> unexpected extension of the geographical and temporal range of
> Mesenosaurus, contributing to our understanding of varanopid dispersal. The
> extended persistence of this basal clade of predatory synapsids,
> underscored by the apparent evolutionary stasis of this genus, is unusual
> among Palaeozoic tetrapods. This phenomenon implies an exceptionally high
> degree of extended ecological resilience across major faunal and
> environmental transitions.
>
> Footnotes
> Electronic supplementary material is available online at
> https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.6084_m9.figshare.c.4693241&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=XVY1cGkZTHOQkBBqCjmGM0W4Yvf2j6hnowxv72exzc0&e= .
>
> =====
>
> (pay-walled)
>
> Kamil Gruntmejer,  Dorota Konietzko‐Meier,  Jordi Marcé‐Nogué,  Adam
> Bodzioch & Josep Fortuny (2019)
> Cranial suture biomechanics in Metoposaurus krasiejowensis (Temnospondyli,
> Stereospondyli) from the upper Triassic of Poland.
> Journal of Morphology (advance online publication)
> doi: https://urldefense.proofpoint.com/v2/url?u=https-3A__doi.org_10.1002_jmor.21070&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=vWBToWKTkjm0-eYtR4_NBlI1hq13Zbwv2r-xojVUvP0&e= 
> https://urldefense.proofpoint.com/v2/url?u=https-3A__onlinelibrary.wiley.com_doi_10.1002_jmor.21070&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=-KnXE4weNbJ1DJXmur3tRkAULBBDSTE8FqVXnYCdnZ8&e= 
>
>
> Cranial sutures connect adjacent bones of the skull and play an important
> role in the absorption of stresses that may occur during different
> activities. The Late Triassic temnospondyl amphibian Metoposaurus
> krasiejowensis has been extensively studied over the years in terms of
> skull biomechanics, but without a detailed description of the function of
> cranial sutures. In the present study, 34 thin sections of cranial sutures
> were examined in order to determine their histovariability and interpret
> their biomechanical role in the skull. The histological model was compared
> with three‐dimensional‐finite element analysis (FEA) simulations of the
> skull under bilateral and lateral biting as well as skull‐raising loads for
> maximum and minimum principal stress. Histologically, only two sutural
> morphologies were recognised in the skull of Metoposaurus: interdigitated
> sutures (commonly associated with compressive stresses) are dominant along
> the entire length of the skull roof and palate; tongue‐and‐groove sutures
> (commonly associated with tensile stresses) are present across the maxilla.
> FEA shows a much more complex picture of stress type and distribution than
> predicted by sutures. Common to both methods is a predominance of
> compressive stresses which act on the skull during biting. The methods
> predict different stress regimes during biting in the posterior part of the
> skull: where histological analysis suggests compression, FEA predicts
> tension. For lateral biting and skull raising, histological and digital
> reconstructions show similar general patterns but with some variations.
>
> ==
>
>
> <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.avg.com_email-2Dsignature-3Futm-5Fmedium-3Demail-26utm-5Fsource-3Dlink-26utm-5Fcampaign-3Dsig-2Demail-26utm-5Fcontent-3Dwebmail&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=79-cA9WiYXURkXkprvmeQoeZypAMMAiFLNZEaW7cEAk&e= > Virus-free.
> www.avg.com
> <https://urldefense.proofpoint.com/v2/url?u=http-3A__www.avg.com_email-2Dsignature-3Futm-5Fmedium-3Demail-26utm-5Fsource-3Dlink-26utm-5Fcampaign-3Dsig-2Demail-26utm-5Fcontent-3Dwebmail&d=DwIFaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=eJcJ66YRGI8lYpyS9HkvYYrS48h3dLvfS0-zOX1EhrI&s=79-cA9WiYXURkXkprvmeQoeZypAMMAiFLNZEaW7cEAk&e= >
> <#m_-3202282900773363243_DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2>
>