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Jurassic ichthyosaurs + Triassic coprolites from Poland + Permian tracks from Italy + more



Ben Creisler
bcreisler@gmail.com

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


Insacco, G., Chairenza, A. A., and Cau, A., 2013/2014
Temnodontosaurus and Stenopterygius (Diapsida: Ichthyosauria)
specimens in the Comiso Natural History Museum (Sicily, Italy).
Natura Rerum 3: 1-12

free pdf:
http://www.edizionibelvedere.it/images/pdf/volume3/1.%20Insacco%20et%20al.pdf


The paleontological collection of the Comiso Natural History Museum
(Sicily, Italy) includes two ichthyosaurian specimens from the Lower
Jurassic Posidonia Shale (southwestern Germany). Based on comparative
morphology, we refer them to Temnodontosaurus and Stenopterygius both
common genera in the Toarcian of Southern Germany.

====

Michal Zaton, Grzegorz Niedzwiedzki, Leszek Marynowski, Karim
Benzerara, Christian Pott, Julie Cosmidis, Tomasz Krzykawski & Pawel
Filipiak (2015)
Coprolites of Late Triassic carnivorous vertebrates from Poland: an
integrative approach.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)
doi:10.1016/j.palaeo.2015.04.009
http://www.sciencedirect.com/science/article/pii/S0031018215001947

Highlights

Vertebrate coprolites from the Upper Triassic of Poland have been studied
Phosphatic groundmass attests for carnivores as coprolite producers
Groundmass is composed of coccoid structures interpreted as fossilized bacteria
Carnivores incidentally/accidentally swallowed plants as evidenced
from inclusions
Preservation of many labile organic compounds indicates rapid faeces
mineralization

Abstract

Vertebrate coprolites derived from Upper Triassic terrestrial deposits
of southern Poland have been subjected to various analytical methods
in order to retrieve information about their composition, producer’s
diet and nature of the microscopic structures preserved in the
groundmass. Morphologically, the coprolites have been classified into
four morphotypes, of which only three were further analysed due to
their good state of preservation. Their groundmass are composed of
francolite, a carbonate-rich apatite, in which abundant coccoid
structures are preserved. Based on various microscopic and organic
geochemical techniques, they are interpreted as fossilized bacteria
which could have mediated the phosphatization of the faeces. The thin
sectioning revealed that the coprolites consist of those containing
exclusively bone remains, and those preserving both bone and plant
remains. Those coprolites preserving only vertebrate remains are
suggestive for exclusive carnivorous diet of the producers. However,
the interpretation of coprolites consisting of both vertebrate and
plant remains is more debatable. Although they may attest to omnivory,
it cannot be excluded that potential producers were carnivorous and
occasionally ingested plants, or accidentally swallowed plant material
during feeding. The latter may involve predation or scavenging upon
other herbivorous animals. The potential producers may have been
animals that foraged in or near aquatic habitats, such as semi-aquatic
archosaurs and/or temnospondyls. This is supported by the presence of
ostracode and other aquatic arthropod remains, and fish scales within
the coprolites, as well as by the presence of specific biomarkers such
as phytanic and pristanic acids, which are characteristic constituents
of fish oil. The preservation of such labile organic compounds as
sterols, palmitin, stearin or levoglucosan attests for rapid,
microbially-mediated mineralization of the faeces at very early stages
of diagenesis.

==

Lorenzo Marchetti, Ausonio Ronchi, Giuseppe Santi, Paolo Schirolli &
Maria Alessandra Conti (2015)
Revision of a classic site for Permian tetrapod ichnology (Collio
Formation, Trompia and Caffaro valleys, N. Italy), new evidences for
the radiation of captorhinomorph footprints.
Palaeogeography, Palaeoclimatology, Palaeoecology (advance online publication)
doi:10.1016/j.palaeo.2015.04.005
http://www.sciencedirect.com/science/article/pii/S003101821500190X

Highlights

Tetrapod ichnotaxonomy based on well-preserved material;
New material of Erpetopus cassinisi and Varanopus isp. (new unnamed species);
Minimum age of the first appearance of Erpetopus in a global context;
Late Early Permian radiation of captorhinomorph footprints confirmed;
Facies-controlled tetrapod ichnofauna.

Abstract

The recent studies on Permian captorhinomorph (non-diapsid eureptile)
footprints from North America, North Africa and Europe raised the
interest on their taxonomic and biostratigraphic significance. They
seem to radiate in the late Early Permian, but the scarcity of
absolute dating in the classic sections bearing these trace fossils is
not helpful in order to unravel their distribution. The continental
Collio Formation cropping out extensively in the central Southern Alps
of Italy can cover this gap of knowledge, since it preserves a rich
testimony of these trace fossils (Erpetopus, Hyloidichnus, Varanopus)
and it is well-constrained from radiometric datings and fossil
content. For this and because of the huge amount of stored but
unanalyzed material, a revision was necessary, through careful
taxonomic assignations. These taxa are here confirmed and/or
identified as being: Amphisauropus kablikae, cf. Batrachichnus isp.,
Dromopus lacertoides, Erpetopus cassinisi, Hyloidichnus bifurcatus,
Limnopus heterodactylus and Varanopus isp. The occurrence of Erpetopus
at the base of the Collio Formation (Kungurian base) suggests its
minimum age of first appearance in a global context: this is a very
important presence in order to build a reliable tetrapod footprint
biostratigraphy during the Permian. The quantity of material yielded
in the different facies of the Collio and Dosso dei Galli Formations
also permit new insights on the paleoenvironments and climatic
settings.

====



David P.G. Bond, Paul B. Wignall, Michael M. Joachimski, Yadong Sun,
Ivan Savov, Stephen E. Grasby, Benoit Beauchamp and Dierk P.G.
Blomeier (2015)
An abrupt extinction in the Middle Permian (Capitanian) of the Boreal
Realm (Spitsbergen) and its link to anoxia and acidification.
Geological Society of America Bulletin (advance online publication)
doi: 10.1130/B31216.1
http://gsabulletin.gsapubs.org/content/early/2015/04/15/B31216.1.abstract

Free pdf:

http://gsabulletin.gsapubs.org/content/early/2015/04/15/B31216.1.full.pdf+html



The controversial Capitanian (Middle Permian, 262 Ma) extinction event
is only known from equatorial latitudes, and consequently its global
extent is poorly resolved. We demonstrate that there were two, severe
extinctions amongst brachiopods in northern Boreal latitudes
(Spitsbergen) in the Middle to Late Permian, separated by a recovery
phase. New age dating of the Spitsbergen strata (belonging to the Kapp
Starostin Formation), using strontium isotopes and δ13C trends and
comparison with better-dated sections in Greenland, suggests that the
first crisis occurred in the Capitanian. This age assignment indicates
that this Middle Permian extinction is manifested at higher latitudes.
Redox proxies (pyrite framboids and trace metals) show that the Boreal
crisis coincided with an intensification of oxygen depletion,
implicating anoxia in the extinction scenario. The widespread and
near-total loss of carbonates across the Boreal Realm also suggests a
role for acidification in the crisis. The recovery interval saw the
appearance of new brachiopod and bivalve taxa alongside survivors, and
an increased mollusk dominance, resulting in an assemblage reminiscent
of younger Mesozoic assemblages. The subsequent end-Permian mass
extinction terminated this Late Permian radiation.