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Re: [dinosaur] Mesosaurs (+ parareptiles as diapsids) (free pdf) + Coahuila State dinosaur find history + more



The first article about mesosaurs and parareptiles is now available in full in open access:


Michel Laurin and Graciela H. PiÃeiro (2017)
A reassessment of the taxonomic position of mesosaurs, and a surprising phylogeny of early amniotes.
Frontiers in Earth SciencesÂ5:88
doi: https://doi.org/10.3389/feart.2017.00088
https://www.frontiersin.org/articles/10.3389/feart.2017.00088/full



We reassess the phylogenetic position of mesosaurs by using a data matrix that is updated and slightly expanded from a matrix that the first author published in 1995 with his former thesis advisor. The revised matrix, which incorporates anatomical information published in the last 20 years and observations on several mesosaur specimens (mostly from Uruguay) includes 17 terminal taxa and 129 characters (four more taxa and five more characters than the original matrix from 1995). The new matrix also differs by incorporating more ordered characters (all morphoclines were ordered). Parsimony analyses in PAUP 4 using the branch and bound algorithm show that the new matrix supports a position of mesosaurs at the very base of Sauropsida, as suggested by the first author in 1995. The exclusion of mesosaurs from a less inclusive clade of sauropsids is supported by a Bremer (Decay) index of 4 and a bootstrap frequency of 66%, both of which suggest that this result is moderately robust. The most parsimonious trees include some unexpected results, such as placing the anapsid reptile Paleothyris near the base of diapsids, and all of parareptiles as the sister-group of younginiforms (the most crownward diapsids included in the analyses). Turtles are placed among parareptiles, as the sister-group of pareiasaurs (and in diapsids, given that parareptiles are nested within diapsids). This unexpected result offers a potential solution to the long-lasting controversy about the position of turtles because previous studies viewed a position among diapsids and among parareptiles as mutually exclusive alternatives.




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On Sun, Oct 15, 2017 at 10:11 AM, Ben Creisler <bcreisler@gmail.com> wrote:

Ben Creisler


Some recent items

The article text has not been published online yet, but here's the posted abstract. Among other things, it proposes that the Parareptilia is within Diapsida and turtles are parareptiles after all!


Michel Laurin and Graciela H. PiÃeiro (2017)

A reassessment of the taxonomic position of mesosaurs, and a surprising phylogeny of early amniotes.

Frontiers in Earth Sciences (article text to come)

doi: 10.3389/feart.2017.00088

https://www.frontiersin.org/articles/10.3389/feart.2017.00088/abstract


Â

We reassess the phylogenetic position of mesosaurs by using a data matrix that is updated and slightly expanded from a matrix that the first author published in 1995 with his former thesis advisor. The revised matrix, which incorporates anatomical information published in the last twenty years and observations on several mesosaur specimens (mostly from Uruguay) includes seventeen terminal taxa and 129 characters (four more taxa and five more characters than the original matrix from 1995). The new matrix also differs by incorporating more ordered characters (all morphoclines were ordered). Parsimony analyses in PAUP 4 using the branch and bound algorithm show that the new matrix supports a position of mesosaurs at the very base of Sauropsida, as suggested by the first author in 1995. The exclusion of mesosaurs from a less inclusive clade of sauropsids is supported by a Bremer (Decay) index of 4 and a bootstrap frequency of 66%, both of which suggest that this result is moderately robust. The most parsimonious trees include some unexpected results, such as placing the anapsid reptile Paleothyris near the base of diapsids, and all of parareptiles as the sister-group of younginiforms (the most crownward diapsids included in the analyses). Turtles are placed among parareptiles, as the sister-group of pareiasaurs (and in diapsids, given that parareptiles are nested within diapsids). This unexpected result offers a potential solution to the long-lasting controversy about the position of turtles because previous studies viewed a position among diapsids and among parareptiles as mutually exclusive alternatives


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A short paper from last year not yet mentioned, with a free pdf:


Sven SACHS, Udo SCHEER & MÃrton RABI (2016)

Reste von protostegiden MeeresschildkrÃten aus dem Cenomanium (Oberkreide) des Kassenberges (MÃlheim an der Ruhr, Westdeutschland).

[Protostegid marine turtle remains from the Cenomanian (Late Cretaceous) of the Kassenberg (MÃlheim an der Ruhr, Western Germany).]

Bericht des Naturwissenschaftlichen Vereins fÃr Bielefeld und Umgegend 54 (2016): 32 - 43


pdf download:


https://www.nwv-bielefeld.de/app/download/10854305697/NwvBerichte2016+-+Sachs%2C+Scheer%2C+Rabi+-+Reste+von+protostegiden+Meeresschildkr%C3%B6ten.pdf?t=1487156179




Postcranial remains of protostegid turtles from the lowermost Cenomanian of MÃlheim an der Ruhr (Western Germany) are described. The material includes fragments from the carapace and appendicular skeleton of a taxon with a medium carapace length of approximately 20-30 cm. The turtle remains supplement the record of this group from the Cenomanian of Germany and the fossil fauna of the Kassenberg.



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Newsletter for the FundaciÃn para el Estudio de los Dinosaurios en Castilla y LeÃn

BoletÃn Informativo n 68, primavera-verano 2017, with an article on Europatitan (in Spanish)

download link:


http://fundaciondinosaurioscyl.com/es/c/?iddoc=1970


https://fundaciondinosaurioscyl.blogspot.com.es/2017/10/boletin-informativo-n-68-primavera.html


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abstracts book with some dinosaur-related items


2017 XV CONGRESO NACIONAL DE PALEONTOLOGÃA in Mexico


http://www.ojs-igl.unam.mx/index.php/Paleontologia/article/view/572


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NEWS AND BLOGS





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Mary Anning film crowdfunding


https://www.viewnews.co.uk/plea-funds-complete-biopic-life-fossil-hunter-mary-anning/


http://www.bridportnews.co.uk/NEWS/15591715.Life_of_world_renowned_fossil_hunter_set_for_big_screen___but_your_help_is_needed/


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History of dinosaur fossils from Coahuila State in Mexico, first discovered by German geologist Erich Haarmann in 1910-1912 (in Spanish)


https://www.debate.com.mx/cultura/Sabias-que-en-Coahuila-se-descubrio-el-primer-dinosaurio-del-pais-20171013-0111.html


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New wireless audio and video technology for tablet computers enhances hadrosaur Antonio and other fossils on display at museum in Villaggio del Pescatore, Italy (in Italian)


http://www.triesteprima.it/eventi/weekend/sito-paleontologico-villaggio-del-pescatore-15-ottobre-2017.html


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Interview with paleontologist Martin KundrÃt, including dinosaur finds in Iran (in Slovak)


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Laiyangosaurus (in Chinese)



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