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Furio M.,Institute Catala Of Paleontologia Miquel Crusafont | Prieto J.,Ludwig Maximilians University of Munich | Van Den Hoek Ostende L.W.,Naturalis Biodiversity Center
Comptes Rendus - Palevol | Year: 2015

For the first time, the heterosoricid genus Dinosorex from the Iberian Peninsula has been studied in detail. Dental morphology and measurements match the original description of the species Dinosorex grycivensis Rzebik-Kowalska and Topachevsky, 1997. This is the first time that the species is reported in southwestern Europe. Biostratigraphically, the last occurrences of Dinosorex in the Vallès-Penedès basin coincide with the transition from early to late Vallesian, together with the first occurrences of the murid Progonomys, at about 9.6. Ma. This is close in time to the estimated moment of final extinction for the genus. Froman evolutionary point of view, it is remarkable that in themore than forty localities in the Vallès-Penedès Basin, spanning three million years, there are no apparent morphological changes. Notably, to date, no occurrences have been reported in central Europe that could link the Ukrainian and Iberian assemblages biogeographically. These results clearly highlight the need of revision of other European forms to place the Iberian finds in a broader scenarioin order to fully comprehend the factors driving the evolution and ultimately extinction of the "terror-shrews". © 2015 Académie des sciences.

Anton M.,CSIC - National Museum of Natural Sciences | Salesa M.J.,CSIC - National Museum of Natural Sciences | Galobart A.,Institute Catala Of Paleontologia Miquel Crusafont | Tseng Z.J.,American Museum of Natural History
Quaternary Science Reviews | Year: 2014

The systematics of the Plio-Pleistocene scimitar toothed felid Homotherium have remained problematic after more than a century of fossil findings in Eurasia, Africa and the Americas. Ranging in age between around 4 million and 10,000 years, fossils of this genus display considerable variation, but the distribution of that variation has largely failed to fit a consistent pattern that would allow a clear distinction between species, especially in the Eurasiatic record. The study of undescribed mandibular and cranial fossils of Homotherium from Pleistocene sites in Spain and Alaska provides new insights into the morphological variability within this widespread genus. The results of our study and comparison of the new material with the published fossils of Homotherium confirm the difficulty in dividing the sample into clear-cut species. The new mandible from Incarcal (Spain) shows in a more dramatic way than before how the sample from that Spanish site encompasses the range of variability observed in the Villafranchian and Pleistocene Eurasiatic record, while older, possibly Ruscinian fossils of Homotherium from East Europe display less reduced lower premolars and probably correspond to a different species. The Alaskan fossils, on the other hand, add to the variability in mandibular and cranial morphology of the late Pleistocene North American record. We find no evidence to allow a species-level division within the Villafranchian-Pleistocene Homotherium sample from Eurasia, which for now is best classified as a single variable species, Homotherium latidens, but there are indications of evolution within the lineage, such as the presence of a pocketed anterior margin of the mandibular masseteric fossa, a feature found in the younger fossils of middle or late Pleistocene age but consistently absent in older specimens. A comparable pattern is found in the American record, where the same mandibular feature is observed in late Pleistocene fossils, although in that continent the "primitive" features of some older Homotherium fossils of Blancan (Pliocene) age are consistent enough to justify their classification in a separate species, Homotherium ischyrus. Only the finding of more complete cranial fossils of middle and late Pleistocene age will reveal if there are additional morphological features (besides the pocketing of the masseteric fossa) that could one day allow the separation of younger populations from those of Late Pliocene and Early Pleistocene age. © 2013 Elsevier Ltd.

Meijer H.J.M.,Institute Catala Of Paleontologia Miquel Crusafont | Meijer H.J.M.,Smithsonian Institution | Meijer H.J.M.,Naturalis Biodiversity Center
Comptes Rendus - Palevol | Year: 2014

A new large representative of the Anseriformes, Garganornis ballmanni n. gen. et n. sp., from the Miocene of Gargano, Italy, is described from the distal end of a left tibiotarsus. G. ballmanni displays morphological features that are characteristic of the Anseriformes, but differs from all extant and fossil Anseriformes, as well as from taxa closely related to Anseriformes. G. ballmanni is characterized by a very wide and shallow fossa intercondylaris, a less pronounced difference in width of the lateral and medial condyle, reduced epicondyli, and a circular opening of the distal canal. G. ballmanni is larger than any living member of Anseriformes, and with an estimated body mass between 15.3 and 22.3. kg, it was most likely flightless. Although the observed similarities between G. ballmanni and basal taxa might indicate that G. ballmanni represents an insular relict of a stem lineage, it is considered more likely that G. ballmanni was a species of waterfowl highly adapted to a terrestrial lifestyle in an insular environment where mammalian carnivores are rare. © 2013 Académie des sciences.

Castanera D.,University of Zaragoza | Razzolini N.L.,Institute Catala Of Paleontologia Miquel Crusafont | Vila B.,University of Zaragoza | Barco J.L.,Paleoymas | Canudo J.I.,University of Zaragoza
PLoS ONE | Year: 2013

Background: Recent work on the Jurassic-Cretaceous transition of the Iberian Range (Spain) has opened a new window onto the interpretation of the trackmakers of some medium-sized tridactyl tracks. The ichnotaxon Therangospodus oncalensis has been described in the Huérteles Formation (Berriasian) and is one of the classical tracks from the area assigned to medium-sized theropods. Methodology/Principal Findings: A review of the type locality of Therangospodus oncalensis (Fuentesalvo tracksite) and other tracksites from the Huérteles Formation (Berriasian) has yielded new information on the morphology, gait and trackmaker identity of the aforementioned ichnospecies. The new data suggest that the trackmaker is an ornithopod rather than a theropod on the basis of the length/width ratio, the anterior triangle lengthwidth ratio, the short steps, the round to quadrangular heel pad impression and the probable manus impressions. Conclusions/Significance: T. oncalensis shows similarities with various tracks from the Berriasian of Europe assigned to Iguanodontipus. The ichnotaxonomical status of this ichnospecies is here considered as Iguanodontipus? oncalensis due to the current state of knowledge of the ichnotaxonomy of medium-sized ornithopod tracks. This reassessment of I? oncalensis also has two significant implications for the palaeoecology of the faunas during the deposition of the Huérteles Formation: 1- the high number and percentage of theropod tracks would be lower than previous papers have suggested. 2- the gregarious behaviour described in the type locality (Fuentesalvo) would be among ornithopods instead of theropods. © 2013 Castanera et al.

Vila B.,University of Zaragoza | Vila B.,Institute Catala Of Paleontologia Miquel Crusafont | Oms O.,Autonomous University of Barcelona | Galobart A.,Institute Catala Of Paleontologia Miquel Crusafont | And 4 more authors.
PLoS ONE | Year: 2013

The study of a small sauropod trackway from the Late Cretaceous Fumanya tracksite (southern Pyrenees, Catalonia) and further comparisons with larger trackways from the same locality suggest a causative relationship between gait, gauge, and body proportions of the respective titanosaur trackmakers. This analysis, conducted in the context of scaling predictions and using geometric similarity and dynamic similarity hypotheses, reveals similar Froude numbers and relative stride lengths for both small and large trackmakers from Fumanya. Evidence for geometric similarity in these trackways suggests that titanosaurs of different sizes moved in a dynamically similar way, probably using an amble gait. The wide gauge condition reported in trackways of small and large titanosaurs implies that they possessed similar body (trunk and limbs) proportions despite large differences in body size. These results strengthen the hypothesis that titanosaurs possessed a distinctive suite of anatomical characteristics that are well reflected in their tracks and trackways. © 2013 Vila et al.

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