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Eggshells from the three extant crocodilian species Crocodylus mindorensis (Philippine Crocodile), Paleosuchus palpebrosus (Cuvier's Smooth-fronted Caiman or Musky Caiman) and Alligator mississippiensis (American Alligator or Common Alligator) were prepared for thin section and scanning electron microscope analyses and are described in order to improve the knowledge on crocodilian eggs anatomy and microstructure, and to find new apomorphies that can be used for identification. Both extant and fossil crocodilian eggs present an ornamentation that vary as anastomo-, ramo- or the here newly described rugosocavate type. The angusticaniculate pore system is a shared character for Crocodylomorpha eggshells and some dinosaurian and avian groups. Previously reported signs of incubated crocodilian eggs were found also on our only fertilised and hatched egg. Paleosuchus palpebrosus presents unique organization and morphology of the three eggshell layers, with a relatively thin middle layer characterised by dense and compact tabular microstructure.

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The amniote eggshell functions as a respiratory structure adapted for the optimal transmission of respiratory gasses to and from the embryo according to its physiological requirements. Therefore amniotes with higher oxygen requirements, such as those that sustain higher metabolic rates, can be expected to have eggshells that can maintain a greater gas flux to and from the egg. Studies of extant amniotes have found that eggshells of reduced porosity impose a limit on the metabolic rate of the offspring. Here we show a highly significant relationship between metabolic rates and eggshell porosity in extant amniotes that predicts highly endothermic metabolic rates in dinosaurs. This study finds the eggshell porosity of extant endotherms to be significantly higher than that of extant ectotherms. Eggshell porosity values of dinosaurs are found to be significantly higherthan that of extant ectotherms, but not extant endotherms. Dinosaur eggshells are commonly preserved in the fossil record, and porosity may be readily identified and measured. This provides a simple tool to identify metabolic rates in extinct egg-laying tetrapods whose eggs possessed a mineralized shell

Portugal has been providing dinosaur remains since, at least, 1863. The 18th century tiles depicting the legend of Our Lady in Cabo Espichel are probably the oldest known dinosaur track illustration. To our knowledge, the first remains found in Portugal were theropod teeth collected near Porto das Barcas (Late Jurassic of Lourinhã) in June 20th, 1863 by the geologist Carlos Ribeiro (1813-1882). The first dinosaur paper was written by Henri Sauvage (1842-1917) published in 1896. All remains collected since 19th century were gathered in a work signed by Albert de Lapparent (1905-1975) and Georges Zbyszewski (1909-1999 ) titled Les Dinosauriens du Portugal (1957) that was a significant milestone in the Portuguese dinosaur paleontology and gives the state-of-the-art by the time. Several dinosaurs are named, described, depicted and mapped in that monograph. The first track record is given by Jacinto Pedro Gomes (1844-1916) in 1916. Concerning the non-scientific literature referring to dinosaurs, in 1884 the newspaper Occidente reports the Bernissart findings in Belgium. In the 1959 occurs the first visit to Portugal of Walter Kühne (1911-1991) from the Free University of Berlin. Further visits and work granted the access to the Guimarota Mine and other Late Jurassic deposits in the 1960’s, 70’s and 80’s with a high number of publications. In the 1980’s and early 1990’s starts a progressive era for dinosaur paleontology in Portugal with the works of Peter Galton, Miguel Telles Antunes, the Natural History Museum, the Museum of Lourinhã and the New University of Lisbon, Oliver Rauhut, and others.

A survey of Hemidactylus turcicus (Reptilia, Gekkonidae) was carried out every 3 weeks from March to November of 1997, in nocturnal transects in the city of Évora, Portugal. In this country this species is strictly nocturnal with a mean daily activity peak at 2hOO A.M (UTC).A model that correlates Activity and Temperature of the air is given. H. turcicus prefers, as microhabitat, walls (78%) and doors (16%) of low used houses. The average height in which they were found is about 3 meters.

Clavicles and interclavicles are plesiomorphically present in Reptilia. However, several groups show reduction or even loss of these elements. Crocodylimorpha, e.g., lost the clavicles, whereas dinosaurs are generally interpreted to only preserve the clavicles, the theropod furcula representing an unique case of fused clavicles. In sauropods, reports of clavicles are relatively frequent in non-titanosauriforms. These elements are elongated, curved, and rather stout bones with a spatulate and a bifurcate end. However, they were always found as single bones, and differ from the relatively short and unbifurcated clavicles found articulated with the scapulae of basal sauropodomorphs. Elements from the Howe Quarry (Late Jurassic; Wyoming, USA) shed new light on these interpretations. Besides the elongated, curved bones (herein named morphotype A), also pairs of symmetric, L-shaped bones were recovered (morphotype B), associated with diplodocid dorsal and cervical vertebrae. Elements resembling morphotype B - articulated between the scapulae - have recently been reported from a diplodocid found near Tensleep, Wyoming. Taphonomic evidence, as well as the fact that they were preserved in symmetrical pairs, therefore implies that morphotype B represents the true sauropod clavicles. Contrary to earlier reports, morphotype A elements from the Howe Quarry, as well as of previously reported specimens show a symmetry plane following the long axis of the elements. It is thus possible that the morphotype A elements were single bones from the body midline. The only such element present in the pectoral girdle of tetrapods are the interclavicle and the furcula. Comparison with crocodilian and lacertiform interclavicles indicates that the bifurcate end of the sauropod elements might represent the reduced transverse processes of the anterior end, and the spatulate end would have covered the coracoids or sternal plates ventrally. The presence of both clavicles and interclavicles in the pectoral girdle stiffens the anterior trunk, and enhances considerably its stability. Such an enforcement might have been needed in diplodocids due to the strong lateral forces induced to the fore-limbs by the posteriorly placed center of mass (due to shorter fore- than hind-limbs), as well as lateral movements of the enormously elongated necks and tails. The absence of clavicles and interclavicles in titanosauriforms coincides with the development of wide-gauge locomotion style. The presence of interclavicles in sauropods supports the recently proposed homology of the furcula with the interclavicle, instead of representing fused clavicles. Interclavicles were thus not lost, but may have remained cartilaginous or have yet to be found in basal dinosauriforms.

Abstract: The paleontological collections of the Museum of Lourinhã, in Portugal, has a rich paleontological collection, particularly of Late Jurassic dinosaurs of the Lourinhã Formation (Kimmeridgian-Tithonian). Most salient highlights comprehend the following dinosaur holotype specimens: stegosaur Miragaia longicollum, theropod Lourinhanosaurus antunesi, sauropod Dinheirosaurus lourinhanensis, ornithopod Draconyx loureiroi, theropod Allosaurus europaeus, and, a mammal, Kuehneodon hahni. Other dinosaur specimens are referred including the nest and eggs and embryos of Lourinhanosaurus. Portugal is very productive in Late Jurassic vertebrates, being the seventh country bearing more dinosaur taxa.

The precursor of the North Atlantic existed between the North American and Iberian blocks from the earliest Jurassic Hettangian and has been ever expanding since. By the Kimmeridgian and Tithonian, when much of the Morrison Fm rocks were deposited, the proto-Atlantic was more than 300 km wide at 27° paleolatitude between North America and Iberia. Macrovertebrate paleontology reveals a unique story to the isolation of Iberia and instead suggest a paleogeographic land connection between North American and Iberia. Torvosaurus, Allosaurus, Ceratosaurus, Stegosaurus, Supersaurus and others have a distribution restricted to Morrison Formation in North America and Lourinhã Formation in Portugal. A novel paleogeographic model is here suggested: (1) around the Middle–Late Jurassic transition there is a major palaeoceanographic and palaeoclimatic reorganization, coincidental to a major eustatic sea-level drop and uplift associated with the Callovian– Oxfordian Atlantic Regressive Event; (2) creating an ephemeral land bridge presenting a temporary opportunity for terrestrial gateways likely across the Flemish Cap and Galician Bank land masses, allowing large dinosaurian taxa to cross the northern proto-Atlantic in both directions; (3) finally, a Callovian–Oxfordian faunal exchange around the 163 Ma, through latest Kimmeridgian at 152 Ma (the age of equivalent genera in both Morrison and Portugal), is was an interval that allowed speciation, but retaining generic similarity of vertebrates. This model is consistent with the chronology and taxonomy required for speciation of the Iberian and American forms, exemplified by the coeval sister-taxa pairs Torvosaurus tanneri and T. gurneyi, Allosaurus fragilis and A. europaeus, or Supersaurus vivianae and S. lourinhanensis. While some of the smaller animals in the fauna show Morrison/Portugal affinities, most from Iberia have European or even Asian affinities. The larger-bodied fauna are more closely related to Morrison than to mainland Europe (except for dacentrurine stegosaurs). The body size differences and affinities of taxa across paleogeography is comparable to what is observed today across the Wallace Line. Migration may have also occurred in both directions. The closest relative of Torvosaurus is likely the European Bathonian Megalosaurus, thus the presence of the genus in North America represents a European migration. On other hand, Allosaurus and Supersaurus origins are consistent with a North American origin, representing an westto-east migration.

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