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News species of Cretaceous mammal and sphenodont + other non-dino papers



From: Ben Creisler
bcreisler@gmail.com

A number of recent non-dino papers that may be of interest to some:


Barbatodon oardaensis

Vlad Aurel Codrea, Alexandru Adrian Solomon, Márton Venczel & Thierry
Smith (2014)A new kogaionid multituberculate mammal from the
Maastrichtian of the Transylvanian Basin, Romania.
Comptes Rendus Palevol (advance online publication)
doi: http://dx.doi.org/10.1016/j.crpv.2014.01.003
http://www.sciencedirect.com/science/article/pii/S163106831400027X

The Latest Cretaceous (Maastrichtian) terrestrial sedimentary
sequences of the Hateg Basin in Transylvania are well known for the
so-called "Hateg Island" vertebrate faunas, which evolved in endemic
(insular?) conditions. In addition to frogs, lizards, turtles,
crocodilians, birds and dinosaurs, peculiar multituberculate mammals
have been recorded, all belonging to the family Kogaionidae. Here, a
new species of the genus Barbatodon is reported from the Maastrichtian
Sard Formation in the Transylvanian Basin (Alba County, Romania).
Barbatodon oardaensis n. sp. is characterized by M1 cusp formula 3:4:2
and is much smaller than the two other Maastrichtian kogaionids from
Transylvania, Barbatodon transylvanicus and Kogaionon ungureanui. The
origin and paleobiogeography of kogaionids are discussed.

===

Priosphenodon minimus

Sebastian Apesteguia & Jose L. Carballido (2014)
A new eilenodontine (Lepidosauria, Sphenodontidae) from the Lower
Cretaceous of central Patagonia
Journal of Vertebrate Paleontology 34(2): 303-317
DOI:10.1080/02724634.2013.803974
http://www.tandfonline.com/doi/full/10.1080/02724634.2013.803974#.UxX9hvldXeI

A new species of eilenodontine sphenodontian, Priosphenodon minimus,
is described from a locality 400 km south of those that yield the
northern Patagonian eilenodontines (the largest known terrestrial
sphenodontians). The new species, represented by subadult specimens,
is both the smallest known eilenodontine and the southernmost record
of the group. Pr. minimus is characterized by a nearly vertical
lateral process of the premaxilla; anteriorly extended frontals that
lack the naso-prefrontal projections; a rounded frontal anterior
process; a prefrontal that posteriorly embraces the nasal; a coronoid
process of the dentary that is tall and with an anterior border that
is vertical in medial view; strong anteromedial flanges on all teeth;
uncommonly dense dental packing; and an anteriorly extended angular
that reaches the midlength of the lower jaw. Differences from juvenile
specimens of Priosphenodon avelasi, such as the interruption of the
prefrontal-jugal contact, are marked. The holotype and associated
material come from early Albian strata, and are therefore around 12
million years older than the northern Patagonian giant sphenodontians.
The new species here described reveals that many of the characters
used to diagnose Kaikaifilusaurus calvoi are widespread, so this taxon
should be regarded as a nomen dubium. Therefore, the genus
Priosphenodon is considered as valid herein, with the new species
assigned to it. A phylogenetic analysis demonstrates the monophyly of
Priosphenodon and suggests that the new taxon represents an incidence
of dwarfing. This discovery increases the morphological disparity
among these specialized herbivores, and provides new climatological
and biostratigraphic information on the terrestrial ecosystems of
Patagonia.


==

Sean P. Modesto, Amy J. Lamb & R. R. Reisz (2014)
The captorhinid reptile Captorhinikos valensis from the lower Permian
Vale Formation of Texas, and the evolution of herbivory in eureptiles.
Journal of Vertebrate Paleontology 34(2): 291-302
DOI:10.1080/02724634.2013.809358
http://www.tandfonline.com/doi/full/10.1080/02724634.2013.809358#.UxX9V_ldXeI


Captorhinikos valensis is a poorly known, multiple-tooth-rowed
captorhinid reptile from the Lower Permian Vale Formation of Texas.
Our reappraisal of C. valensis reveals it to be a small moradisaurine,
exhibiting a maximum of five rows of bullet-shaped teeth in the
multiple-rowed region of both the maxilla and the dentary. The
slightly radiating organization of the tooth rows distinguishes C.
valensis from the parallel arrangement of the tooth rows exhibited by
all other moradisaurines. Captorhinikos valensis is also
distinguishable from the coeval moradisaurine Labidosaurikos meachami
by a more conspicuously denticulated, broader, 'U'-shaped transverse
flange of the pterygoid, a plesiomorphic morphology shared with the
large, single-rowed captorhinid Labidosaurus hamatus. Postcranial
information is limited to two short series of presacral vertebrae not
associated with the cranial materials; open neurocentral sutures are
present in one specimen, indicating immaturity at death. We
investigated the relationships of C. valensis to other captorhinids by
adding it to the data matrix of a previously published analysis that
included several moradisaurine captorhinids. A branch-and-bound PAUP
analysis discovered a single optimal tree. Whereas a previous analysis
of captorhinid interrelationships found the (undifferentiated) genus
Captorhinikos to fall outside of a clade composed of L. hamatus and
the large moradisaurines, our analysis recovered C. valensis in a
clade with the genera Labidosaurikos, Gansurhinus, Moradisaurus, and
Rothianiscus (i.e., Moradisaurinae sensu stricto), and Captorhinikos
chozaensis as the sister species of a clade that includes L. hamatus
and Moradisaurinae s.s.; Captorhinikos chozaensis is no longer
classifiable as a moradisaurine (according to our phylogenetic
definition for the group), and should be assigned to a new genus.
Stratigraphic calibration of our captorhinid phylogeny indicates that
moradisaurines evolved by the middle Kungurian (middle Leonardian).

==


Márton Rabi, Vladimir B. Sukhanov, Vera N. Egorova, Igor Danilov &
Walter G. Joyce (2014)
Osteology, relationships, and ecology of Annemys (Testudines,
Eucryptodira) from the Late Jurassic of Shar Teg, Mongolia, and
phylogenetic definitions for Xinjiangchelyidae, Sinemydidae, and
Macrobaenidae.
Journal of Vertebrate Paleontology 34(2): 327-352
DOI:10.1080/02724634.2013.807274
http://www.tandfonline.com/doi/full/10.1080/02724634.2013.807274#.UxX9sPldXeI


A complete description of the xinjiangchelyid turtles Annemys levensis
and A. latiens is provided, based on all available material from the
Upper Jurassic type locality of Shar Teg, Mongolia. Annemys latiens
was previously known almost exclusively from shell material, but an
undescribed skull from Shar Teg is referable to this species and its
distinct morphology confirms the presence of two taxa at this
locality. Annemys latiens has an elongated skull that markedly differs
in proportions from those of A. levensis and resembles the shape of
some recent, piscivorous turtles. The overall similarity of the shells
of the two Annemys species combined with significant differences in
the skull indicate that these turtles probably partitioned the aquatic
niche by exploring different feeding strategies. Among
xinjiangchelyids, at least three different skull morphotypes can be
differentiated, which implies a moderate level of ecological
diversification among Late Jurassic Asian turtles. Phylogenetic
analysis weakly supports the inclusion of Annemys spp. into
Xinjiangchelyidae and places xinjiangchelyids at the stem of
Testudines, but the latter result is considered tentative.
Phylogenetic definitions of Xinjiangchelyidae, Sinemydidae, and
Macrobaenidae are provided for nomenclatural clarity and precision.

===

Christian Püntener, Jean-Paul Billon-Bruyat, Loïc Bocat, Jean-Pierre
Berger & Walter G. Joyce
Taxonomy and phylogeny of the turtle Tropidemys langii Rütimeyer,
1873, based on new specimens from the Kimmeridgian of the Swiss Jura
Mountains
Journal of Vertebrate Paleontology 34(2): 353-374
DOI:10.1080/02724634.2013.804412
http://www.tandfonline.com/doi/full/10.1080/02724634.2013.804412#.UxX9x_ldXeI


The fossil turtle Tropidemys langii is a representative of
Plesiochelyidae, a traditionally recognized group of Late Jurassic
turtles diagnosed by the presence of three cervical scutes and adapted
to life in the sea. Tropidemys langii was previously only known from
fossilized carapaces and, possibly, plastra from Europe, most notably
the famous 'Solothurn Turtle Limestone' of Switzerland. Due to the
sparse fossil record of Tropidemys langii, several questions
concerning its taxonomy and phylogeny have remained unanswered. Here,
new material of Tropidemys langii is reported from the Kimmeridgian of
Porrentruy, Canton Jura, Switzerland. In addition to three
well-preserved carapaces, associated plastra and limb bones (humerus
and femur) are described for the first time. The type specimens of
'Tropidemys valanginiensis' and 'Pelobatochelys blakii' lack
diagnostic characters, but can nevertheless be referred to Tropidemys.
A potential extension of the lineage into the Early Cretaceous is
uncertain, however, because the type locality of 'Tropidemys
valanginiensis' is dubious. A cladistic analysis shows that Tropidemys
langii is sister to Plesiochelys solodurensis, thereby tentatively
confirming for the first time the monophyly of Plesiochelyidae using
cladistic arguments.

===


Cheng Ji, Da-Yong Jiang, Olivier Rieppel, Ryosuke Motani, Andrea
Tintori & Zuo-Yu Sun (2014)
A new specimen of Nothosaurus youngi from the Middle Triassic of Guizhou, China
Journal of Vertebrate Paleontology 34(2): 465-470
DOI:10.1080/02724634.2013.808204
http://www.tandfonline.com/doi/full/10.1080/02724634.2013.808204#.UxX99_ldXeI

[no abstract]


===


Roksana Skrzyck (2014)
Revision of two relic actinopterygians from the Middle or Upper
Jurassic Karabastau Formation, Karatau Range, Kazakhstan.
Alcheringa (advance online publication)
DOI:10.1080/03115518.2014.880267
http://www.tandfonline.com/doi/full/10.1080/03115518.2014.880267#.UxYFhvldXeI


Three hundred and forty-six articulated fossil specimens of two
species from the Middle or Upper Jurassic Karabastau Formation of the
Karatau Range (Kazakhstan, Asia) were studied to revise two
little-known palaeonisciform fish: Pteroniscus turkestanensis and
Morrolepis aniscowitchi. Detailed morphological analysis shows that P.
turkestanensis, Daqingshaniscus longiventralis and Uighuroniscidae
form a closely related group. They are far more distantly related to
the Palaeoniscidae than previously inferred. The first detailed
scanning electron microscopy of the unique scale cover of M.
aniscowitchi is presented. Morrolepis is found to be devoid of
denticles on the surface of the bones, scales and lepidotrichia--so far
considered to be a key coccolepidid characteristic. However, it bears
exceptionally robust lateral line scales. Comparison of the axial
skeletons of M. aniscowitchi and Morrolepis andrewsi reveals their
close affinities within Coccolepididae. The axial skeleton, despite
its rare preservation in palaeonisciforms, may be taxonomically
informative, at least at the family level. The Karatau
palaeonisciforms, being among the youngest examples of basal
actinopterygians (persisting in Asia through the late Mesozoic),
possess a set of conservative morphological characters that suggest
they were relictual taxa by Jurassic times, thus highlighting some
freshwater systems as refuges for plesiomorphic taxa.

===

Sidney R. Ash (2014)
Contributions to the Upper Triassic Chinle flora in the American southwest.
Palaeobiodiversity and Palaeoenvironments (advance online publication)
DOI: 10.1007/s12549-014-0150-3
http://link.springer.com/article/10.1007/s12549-014-0150-3

This article summarises an investigation of three selected species of
fossil gymnosperms collected from the Upper Triassic Chinle Formation
of the American southwest. Included here is an emended diagnosis of
Lindleycladus arizonicus (Daugherty) comb. nov., a description of
Elatocladus puercoensis sp. nov., and a redescription, based on new
material, of the contentious plant fossil Dechellyia gormanii Ash.
Also, the evidence (excisions and galls) of insect predation found on
some of the leaves of the new specimens of D. gormanii is described
and compared with that reported earlier on other fossil leaves in the
Chinle Formation.

===