Ben Creisler | 3 Sep 17:12 2015
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Dakotadon (Early Cretaceous ornithopod) redescribed

Ben Creisler
bcreisler <at> gmail.com

An open access preprint in PeerJ:

Clint A Boyd and Darrin C Pagnac (2015)
Insight on the anatomy, systematic relationships, and age of the Early
Cretaceous ankylopollexian dinosaur Dakotadon lakotaensis.
PeerJ PrePrints 3:e1649
doi: https://dx.doi.org/10.7287/peerj.preprints.1135v2
https://peerj.com/preprints/1135/
https://peerj.com/preprints/1135.pdf

Knowledge regarding the early evolution within the dinosaurian clade
Ankylopollexia drastically increased over the past two decades, in
part because of an increase in described taxa from the Early
Cretaceous of North America. These advances motivated the recent
completion of extensive preparation and conservation work on the
holotype and only known specimen of Dakotadon lakotaensis, a basal
ankylopollexian from the Lakota Formation of South Dakota. That
specimen (SDSM 8656) preserves a partial skull, lower jaws, a single
dorsal vertebra, and two caudal vertebrae. That new preparation work
exposed several bones not included in the original description and
revealed that other bones were previously misidentified. The presence
of extensive deformation in areas of the skull is also noted that
influenced inaccuracies in prior descriptions and reconstructions of
this taxon. In addition to providing an extensive re-description of D.
lakotaensis, this study reviews previously proposed diagnoses for this
taxon, identifies two autapomorphies, and provides an extensive
differential diagnosis. Dakotadon lakotaensis is distinct from the
(Continue reading)

Ben Creisler | 2 Sep 20:01 2015
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Montana sauropod + Dimetrodon in Texas + Carnotaurus skull mechanics + more

Ben Creisler
bcreisler <at> gmail.com

Some recent news and blog items:

Moving fossils of possible new Jurassic Montana sauropod species

http://missoulian.com/news/local/huge-dinosaur-fossils-hauled-to-billings-for-cleaning-may-be/article_ab01b1c4-0592-5cfe-a999-3ccbf68bd7d7.html

http://mtstandard.com/news/local/huge-dinosaur-fossils-hauled-to-billings-for-cleaning-may-be/article_2456dca1-7076-5908-a5ca-65f77ef4ebe6.html

video

http://www.kulr8.com/story/29937927/potential-new-species-of-dinosaur-transported-to-billings

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Bob Bakker and Dimetrodon site in Texas

http://www.texasobserver.org/big-dig/

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Padillasaurus from Colombia, intereview with José Luis Carballido (in Spanish)

http://www.zocalo.com.mx/seccion/articulo/descubren-una-nueva-especie-de-dinosaurio-sauropodo-1441204258

==

Plesiosaurs that used to be dinosaurs
(Continue reading)

Ben Creisler | 2 Sep 19:12 2015
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Eunotosaurus skull + amphisbaenian lizard origin + sawfish "teeth"

Ben Creisler
bcreisler <at> gmail.com

A number of recent papers that may be of interest:

G. S. Bever, Tyler R. Lyson, Daniel J. Field & Bhart-Anjan S. Bhullar (2015)
Evolutionary origin of the turtle skull.
Nature (advance online publication)
doi:10.1038/nature14900
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14900.html

Transitional fossils informing the origin of turtles are among the
most sought-after discoveries in palaeontology. Despite strong genomic
evidence indicating that turtles evolved from within the diapsid
radiation (which includes all other living reptiles), evidence of the
inferred transformation between an ancestral turtle with an open,
diapsid skull to the closed, anapsid condition of modern turtles
remains elusive. Here we use high-resolution computed tomography and a
novel character/taxon matrix to study the skull of Eunotosaurus
africanus, a 260-million-year-old fossil reptile from the Karoo Basin
of South Africa, whose distinctive postcranial skeleton shares many
unique features with the shelled body plan of turtles. Scepticism
regarding the status of Eunotosaurus as the earliest stem turtle
arises from the possibility that these shell-related features are the
products of evolutionary convergence. Our phylogenetic analyses
indicate strong cranial support for Eunotosaurus as a critical
transitional form in turtle evolution, thus fortifying a
40-million-year extension to the turtle stem and moving the ecological
context of its origin back onto land. Furthermore, we find unexpected
evidence that Eunotosaurus is a diapsid reptile in the process of
(Continue reading)

Ben Creisler | 2 Sep 00:04 2015
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Proposed terminology of theropod teeth

Ben Creisler
bcreisler <at> gmail.com

A new online paper:

Christophe Hendrickx, Octávio Mateus & Ricardo Araújo (2015)
A proposed terminology of theropod teeth (Dinosauria, Saurischia).
Journal of Vertebrate Paleontology (advance online publication)
DOI:10.1080/02724634.2015.982797
http://www.tandfonline.com/doi/full/10.1080/02724634.2015.982797#abstract

Theropod teeth are typically not described in detail, yet these
abundant vertebrate fossils are not only frequently reported in the
literature, but also preserve extensive anatomical information. Often
in descriptions, important characters of the crown and ornamentations
are omitted, and in many instances, authors do not include a
description of theropod dentition at all. The paucity of information
makes identification of isolated teeth difficult and taxonomic
assignments uncertain. Therefore, we here propose a standardization of
the anatomical and morphometric terms for tooth anatomical subunits,
as well as a methodology to describe isolated teeth comprehensively.
As a corollary, this study exposes the importance of detailed
anatomical descriptions with the utilitarian purpose of clarifying
taxonomy and identifying isolated theropod teeth.

SUPPLEMENTAL DATA—Supplemental materials are available for this
article for free at www.tandfonline.com/ujvp

Ben Creisler | 1 Sep 17:33 2015
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Neuquensaurus (titanosaur from Argentina) morphological diversity

Ben Creisler
bcreisler <at> gmail.com

A new online paper:

V. Zurriaguz (2015)
Morphological diversity of Neuquensaurus Powell, 1992 (Sauropoda;
Titanosauria): insights from geometric morphometrics applied to the
vertebral centrum shape.
Historical Biology (advance online publication)
DOI:10.1080/08912963.2015.1079630
http://www.tandfonline.com/doi/full/10.1080/08912963.2015.1079630#abstract

Neuquensaurus is a small-sized titanosaur from the Upper Cretaceous of
Patagonia, Argentina, for which two species were recognised in the
past (Neuquensaurus australis and Neuquensaurus robustus). Given that
such division was only based on the relative robustness of the limb
bones, the validity of the species N. robustus has been questioned. In
this work, we studied the morphological variation of the vertebrae of
this genus through geometric morphometric techniques and the
description of relevant anatomical features in order to assess if
there are one or more morphotypes within Neuquensaurus. We found two
distinguishable morphotypes, one belonging to N. australis and other
that includes specimens assigned to both N. australis and N. robustus.
The occurrence of a posterior cervical vertebra with a particular
anatomical feature (i.e. four sprl) could indicate the presence of
another taxon than N. australis in the studied sample. Although the
validity of the species N. robustus cannot be discussed on the basis
of the current data, our study supports the hypothesis of at least two
different morphotypes of Neuquensaurus (which could be related to
(Continue reading)

soledad.esteban | 1 Sep 14:58 2015

Workshop Geometric Morphometrics in R, January 18-22, Barcelona.


Dear colleagues,

The second edition of our course "Geometrics Morphometrics in R" has just opened registration. Basic
knowledge of R is required.
 
Dates: January 18th-22nd, 2016.

Instructor: Dr. Julien Claude (Institut des Sciences de l’Évolution de Montpellier, France), author
of Morphometrics with R (http://www.springer.com/us/book/9780387777894). 

PLACE:  Facilities of the Centre de Restauració i Interpretació Paleontologica, Els Hostalets de
Pierola,  Barcelona (Spain). 

Concepts in geometric morphometrics will be taught using a series of original data sets and working in R for
solving a series of tasks. The course will start with an introduction to R and will rapidly go into shape
analysis with measurements, landmark data and outlines. The participants are welcome to bring their own
data and problems so that we may find R solutions.

Registration and more info: http://www.transmittingscience.org/courses/gm/gm-in-r/

PROGRAM: http://www.transmittingscience.org/courses/gm/gm-in-r/#Program
 
This course is organized by Transmitting Science, the Institut Català de Paleontologia and the Centre
de Restauració i Interpretació Paleontologica.
 
Please feel free to distribute this information between your colleagues if you consider it appropriate.
With best regards

Soledad De Esteban-Trivigno
(Continue reading)

Mickey Mortimer | 1 Sep 02:34 2015
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Museum d'Histoire naturelle de Boulogne-sur-Mer collection fate?

According to Young et al. (2014), the Museum d'Histoire naturelle de Boulogne-sur-Mer in France was
closed in 2003.  Does anyone know what happened to their collections?

Mickey Mortimer
 		 	   		  

Ben Creisler | 31 Aug 17:28 2015
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Ankylosaurid tail club evolution

Ben Creisler
bcreisler <at> gmail.com

A new paper:

Victoria M. Arbour and Philip J. Currie (2015)
Ankylosaurid dinosaur tail clubs evolved through stepwise acquisition
of key features.
Journal of Anatomy (advance online publication)
DOI: 10.1111/joa.12363
http://onlinelibrary.wiley.com/doi/10.1111/joa.12363/abstract

Ankylosaurid ankylosaurs were quadrupedal, herbivorous dinosaurs with
abundant dermal ossifications. They are best known for their
distinctive tail club composed of stiff, interlocking vertebrae (the
handle) and large, bulbous osteoderms (the knob), which may have been
used as a weapon. However, tail clubs appear relatively late in the
evolution of ankylosaurids, and seemed to have been present only in a
derived clade of ankylosaurids during the last 20 million years of the
Mesozoic Era. New evidence from mid Cretaceous fossils from China
suggests that the evolution of the tail club occurred at least 40
million years earlier, and in a stepwise manner, with early
ankylosaurids evolving handle-like vertebrae before the distal
osteoderms enlarged and coossified to form a knob.

Blog:

http://pseudoplocephalus.blogspot.com/2015/08/how-ankylosaur-got-its-tail-club.html

(Continue reading)

Ben Creisler | 31 Aug 07:26 2015
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Marine Reptiles from Luoping Biota of Middle Triassic of China

Ben Creisler
bcreisler <at> gmail.com

A recent paper not yet mentioned.

I have not been able to get the pdf to download successfully, however.

WEN Wen, ZHANG Qi-yue, LIU Jun, HU Shi-xue, ZHOU Chang-yong, HUANG
Jin-yuan and XIE Tao (2015)
New Progress in the Study of Marine Reptiles from the Luoping Biota of
Middle Triassic Anisian Period.
Acta Geoscientica Sinica 36(4):385-393
http://www.cagsbulletin.com/dqxben/ch/reader/view_abstract.aspx?file_no=20150401&flag=1

pdf:

http://www.cagsbulletin.com/dqxben/ch/reader/create_pdf.aspx?file_no=20150401&flag=1&journal_id=dqxben&year_id=2015

The Luoping Biota was discovered in 2007 by the Chengdu Center of
China Geological Survey during 1:50000 regional mapping works at
Dawazi Village, Luoxiong Town, 15 km southeast of Luoping City, Yunnan
Province. The interval containing the Luoping biota is the middle to
upper part of Member II of the Guanling Formation. The fossil
assemblage of the Luoping biota is a mixture of marine animals,
terrestrial plants and a few terrestrial animals. To date, more than
ten fossil groups have been recovered, which include marine reptiles,
fishes, arthropods, echinoderms, ammonites, bivalves, gastropods,
lingulid brachiopods, foraminifers, and plants. The Luoping Biota is
one of the most diverse Triassic marine fossil Lagerstatten records in
the world. The age of the Luoping biota is assigned to the Pelsonian
(Continue reading)

Poekilopleuron | 31 Aug 07:14 2015
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Centrosaurus bonebed mystery

Good day,

I would like to ask if it was already resolved what conditions caused the 
demise of around 667 Centrosaurus individuals in the famous "Hilda bonebed" 
in Alberta? Is the idea of a huge flash flood still supported? And the same 
for Clevelan Lloyds allosaurs - does the idea of deadly natural trap still 
hold? Thank you very much, Tom
Ben Creisler | 30 Aug 00:21 2015
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Vertebrates at Permian-Triassic boundary in Karoo Basin (free pdf)

Ben Creisler
bcreisler <at> gmail.com

A new online paper in open access:

Robert A. Gastaldo, Sandra L. Kamo, Johann Neveling, John W. Geissman,
Marion Bamford and Cindy V. Looy (2015)
Is the vertebrate-defined Permian-Triassic boundary in the Karoo
Basin, South Africa, the terrestrial expression of the end-Permian
marine event?
Geology (advance online publication)
doi: 10.1130/G37040.1
http://geology.gsapubs.org/content/early/2015/08/28/G37040.1.abstract

Free pdf:
http://geology.gsapubs.org/content/early/2015/08/28/G37040.1.full.pdf+html

The end-Permian extinction records the greatest ecological catastrophe
in Earth history. The vertebrate fossil record in the Karoo Basin,
South Africa, has been used for more than a century as the standard
for understanding turnover in terrestrial ecosystems, recently claimed
to be in synchrony with the marine crisis. Workers assumed that
systematic turnover at the Dicynodon assemblage zone boundary,
followed by the appearance of new taxa directly above the base of the
Lystrosaurus assemblage zone, is the continental expression of the
end-Permian event and recovery. To test this hypothesis, we present
the first high-precision age on strata close to the inferred
Permian-Triassic boundary. A U-Pb isotope dilution–thermal ionization
mass spectrometry zircon age of 253.48 ± 0.15 Ma (early Changhsingian)
is from a silicified ash layer ~60 m below the current
(Continue reading)


Gmane