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Triassic ichthyosaur from Sicily and Cretaceous Dorsetochelys from Europe



From: Ben Creisler
bcreisler@gmail.com

Two recent non-dino papers:

Cristiano dal Sasso, Gianni Insacco, Alfio Alessandro Chiarenza,
Davide di Franco & Agatino Reitano (2014)
First record of ichthyosaurs in Sicily (Upper Triassic of Monte
Scalpello, Catania Province).
Rivista italiana di Paleontologia e Stratigrafia 120(1): 71-82
http://www.rivistaitalianadipaleontologia.it/pub/index.php/contents-1997-2014/79-abstracts/139-abstracts-vol-120-1-2014


Here we report for the first time on the presence of ichthyosaurs in
Sicily, southern Italy. The deposit of origin (Mufara Formation) can
be dated to the upper Carnian (Tuvalian substage) based on a typical
association of ammonites, one of which (Shastites sp.) is embedded in
the sediment still encrusting one of the bone specimens recently
found. The latter consist of two isolated vertebral centra that are
referred to the Ichthyosauria thanks to their disk-like shape (i.e.
they are much taller than long) combined with the amphicelous
condition, lack of transverse processes, and presence of rib
articulations on the central sides. The largest specimen is more
precisely an anterior dorsal vertebra from an adult individual,
ascribed to Shastasauridae indet. By the presence of elongated
reniform diapophyseal facets, cranially not truncated, and absence of
parapophyses. The smaller specimen represents an anterior cervical
element from an immature individual of a likely smaller-sized,
indeterminate taxon. These finds indicate that the biodiversity of the
Monte Scalpello Triassic fauna is higher than previously known, but
above all represent the southernmost occurrence of Triassic
ichthyosaurs in the western Tethys basin.
==

A. Pérez-García (2014)
Revision of the poorly known Dorsetochelys typocardium, a relatively
abundant pleurosternid turtle (Paracryptodira) in the Early Cretaceous
of Europe.
Cretaceous Research 49: 152-162
doi: http://dx.doi.org/10.1016/j.cretres.2014.02.015
http://www.sciencedirect.com/science/article/pii/S0195667114000287

Pleurosternidae is one of two clades of freshwater turtles recorded
both in the European Late Jurassic and Early Cretaceous records.
Pleurosternon bullockii is the only well-known Early Cretaceous
representative of this clade. "Pleurosternon" typocardium, from
England, was defined in the 19th century. However, available
information on it is very limited as it has never been thoroughly
revised. In fact, all attributions of elements to its plastron have
already been considered doubtful. In addition, many carapace regions
were poorly understood and some characters have been wrongly
interpreted in several papers. More than ten specimens are here
attributed to this taxon, until now only known by the shell. Many of
these specimens have never been described or figured. Therefore, its
shell is characterized in detail herein. This analysis paves the way
to refuting the validity of several taxa, supporting the recently
proposed new combination of Dorsetochelys typocardium. This study also
extends the palaeobiogeographic range of distribution of this species,
so far recognized only from records from England. As a result, the
known post-Jurassic record of Pleurosternidae is identified as
exclusively composed of two taxa: Pleurosternon bullockii and
Dorsetochelys typocardium.