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Re: Therapsid skull neutron tomography + Dinilysia, snake from Argentina + Kimbetopsalis, new multituberculate



The pdf is now free:

Thomas E. Williamson, Stephen L. Brusatte, Ross Secord and Sarah Shelley (2015)
A new taeniolabidoid multituberculate (Mammalia) from the middle
Puercan of the Nacimiento Formation, New Mexico, and a revision of
taeniolabidoid systematics and phylogeny.
Zoological Journal of the Linnean Society (advance online publication)
DOI: 10.1111/zoj.12336
http://onlinelibrary.wiley.com/doi/10.1111/zoj.12336/abstract

Free pdf:

http://onlinelibrary.wiley.com/doi/10.1111/zoj.12336/pdf

On Mon, Oct 5, 2015 at 12:05 AM, Ben Creisler <bcreisler@gmail.com> wrote:
> Ben Creisler
> bcreisler@gmail.com
>
>
> Some new and recent non-dino items that may be of interest to some:
>
>
> In open access:
>
> Michael Laaß & Burkhard Schillinger (2015)
> Reconstructing the Auditory Apparatus of Therapsids by Means of
> Neutron Tomography.
> Physics Procedia 69: 628–635
> doi:10.1016/j.phpro.2015.07.089
> http://www.sciencedirect.com/science/article/pii/S1875389215006999
>
> The internal cranial structure of mammalian ancestors, i.e. the
> therapsids or “mammal-like reptiles”, is crucial for understanding the
> early mammalian evolution. In the past therapsid skulls were
> investigated by mechanical sectioning or serial grinding, which was a
> very time-consuming and destructive process and could only be applied
> to non-valuable or poorly preserved specimens. As most therapsid
> skulls are embedded in terrestrial iron-rich sediments of Late Permian
> or Triassic age, i.e. so called “Red beds”, a successful investigation
> with X-Rays is often not possible.
>
> We successfully investigated therapsid skulls by means of neutron
> tomography at the facility ANTARES at FRM II in Munich using cold
> neutron radiation. This kind of radiation is able to penetrate
> iron-rich substances in the range between 5 and 15 cm and produces a
> good contrast between matrix and bones, which enables segmentation of
> internal cranial structures such as bones, cavities and canals of
> nerves and blood vessels. In particular, neutron tomography combined
> with methods of 3D modeling was used here for the investigation and
> reconstruction of the auditory apparatus of therapsids.
>
> ===
>
>
> Kimbetopsalis--Paleocene rather Mesozoic, but of interest in post-K
> extinction recovery story
>
> Thomas E. Williamson, Stephen L. Brusatte, Ross Secord and Sarah Shelley 
> (2015)
> A new taeniolabidoid multituberculate (Mammalia) from the middle
> Puercan of the Nacimiento Formation, New Mexico, and a revision of
> taeniolabidoid systematics and phylogeny.
> Zoological Journal of the Linnean Society (advance online publication)
> DOI: 10.1111/zoj.12336
> http://onlinelibrary.wiley.com/doi/10.1111/zoj.12336/abstract
>
>
>
> Multituberculates were amongst the most abundant and taxonomically
> diverse mammals of the late Mesozoic and the Palaeocene, reaching
> their zenith in diversity and body size in the Palaeocene.
> Taeniolabidoidea, the topic of this paper, includes the largest known
> multituberculates, which possess highly complex cheek teeth adapted
> for herbivory. A new specimen from the early Palaeocene (middle
> Puercan; biochron Pu2) of the Nacimiento Formation, New Mexico
> represents a new large-bodied taeniolabidoid genus and species,
> Kimbetopsalis simmonsae. A phylogenetic analysis to examine the
> relationships within Taeniolabidoidea that includes new information
> from Kimbetopsalis gen. et sp. nov. and gen. nov. and from new
> specimens of Catopsalis fissidens, first described here, and data from
> all other described North American and Asian taeniolabidoids. This
> analysis indicates that Catopsalis is nonmonophyletic and justifies
> our transfer of the basal-most taeniolabidoid ‘Catopsalis’ joyneri to
> a new genus, Valenopsalis. Kimbetopsalis and Taeniolabis form a clade
> (Taeniolabididae), as do the Asian Lambdopsalis, Sphenopsalis, and
> possibly also Prionessus (Lambdopsalidae). Taeniolabidoids underwent a
> modest taxonomic radiation during the early Palaeocene of North
> America and underwent a dramatic increase in body size, with
> Taeniolabis taoensis possibly exceeding 100 kg. Taeniolabidoids appear
> to have gone extinct in North America by the late Palaeocene but the
> appearance of lambdopsalids in the late Palaeocene of Asia suggests
> that they dispersed from North America in the early to middle
> Palaeocene.
>
>
> News:
>
> http://news.unl.edu/newsrooms/unltoday/article/undergrad-discovers-new-mammal-species/
>
> http://www.bbc.com/news/science-environment-34414923
>
> http://in.reuters.com/article/2015/10/05/science-mammal-idINKCN0RZ08020151005
>
>
> ==
>
> Dinilysia
>
> Free pdf:
>
> L.N. Triviño & A.M. Albino (2015).
>
> Hallazgo de restos de la serpiente Dinilysia patagonica Smith-Woodward
> 1901 en una nueva localidad del Santoniano de Patagonia, Argentina.
> (in Spanish)
> [Record of remains of the snake Dinilysia patagonica Smith-Woodward
> 1901 in a new locality of the Santonian of Patagonia, Argentina.]
> Estudios Geológicos 71(2): e033
> http://dx.doi.org/10.3989/egeol.41858.347
> http://estudiosgeol.revistas.csic.es/index.php/estudiosgeol/article/view/927/1028
>
> Resumen
>
>
>
> En este trabajo se describen nuevos restos de la serpiente cretácica
> Dinilysia patagonica recuperados en la localidad Barreales Norte,
> Formación Bajo de la Carpa (Santoniano superior), provincia del
> Neuquén, Argentina. El material comprende la parte posterior de un
> cráneo parcialmente conservado y articulado con un fragmento del hueso
> compuesto, atlas y axis. Además, se preservaron seis secciones de
> columna vertebral con vértebras precloacales. La asignación a
> Dinilysia patagonica se basa en: cráneo de tamaño grande, otooccipital
> con largo proceso paraoccipital adosado a un elongado supratemporal
> que se extiende más allá del nivel del cóndilo occipital; cresta
> sagital del parietal bien desarrollada y continua con la cresta del
> supraoccipital; proótico en forma de I cursiva; vértebras anchas,
> cortas y robustas; prezigapófisis largas y muy inclinadas sobre la
> horizontal; canal neural pequeño y trilobulado; proceso
> prezigapofisario reducido; arcos neurales aplanados con el margen
> posterior recto. Este material agrega una nueva localidad al norte del
> río Neuquén para la distribución de la especie en el Cretácico
> superior.
>
> **
>
> In this study, we describe new remains of the Cretaceous snake
> Dinilysia patagonica from beds of the locality Barreales Norte, Bajo
> de la Carpa Formation (Upper Santonian), Neuquén Province, Argentina.
> The material comprises the back of a partially preserved skull,
> articulated with a fragment of the compound bone, atlas and axis.
>
> Additionally, six fragments of precloacal vertebrae have been
> preserved. The assignation to Dinilysia patagonica is based on: large
> skull, otooccipital with long paraoccipital process adjacent to an
> elongate supratemporal thatextends farther the level of the occipital
> condyle; well developed sagital crest of parietal bone, continuously
> joined with the supraoccipital crest; italics I-like prootic; wide,
> short and robust vertebrae; prezygapophyses long and highly inclined
> above the horizontal; triangular section of vertebral centrum; reduced
> prezygapophyseal process; flattened neural arches with straight
> posterior edge. This material adds a new Upper Cretaceous location for
> the distribution of the species at the north of the Neuquén River.
>
> =============