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The Sociedade de História Natural in Torres Vedras, Portugal houses an extensive collection of as yet undescribed dinosaur tracks with ornithopod affinities. They have been collected from different Late Jurassic (Kimmeridgian-Tithonian) geological formations (Praia de Amoreira-Porto Novo, Alcobaça, Sobral, and Freixial) that outcrop along the Portuguese coast, and belong to two different sub-basins of the Lusitanian Basin (the Consolação and Turcifal sub-basins). Three main morphotypes can be distinguished on the basis of size, mesaxony and the morphology of the metatarsophalangeal pad impression. The minute to small-sized morphotype is similar to the Anomoepus-like tracks identified in other Late Jurassic areas. The small to medium-sized morphotype resembles the Late Jurassic-Early Cretaceous ichnotaxon Dinehichnus, already known in the Lusitanian Basin. Interestingly, these two morphotypes can be distinguished qualitatively (slightly different size, metatarsophalangeal pad impression and digit morphology) but are nevertheless difficult to discriminate by quantitatively analysing their length-width ratio and mesaxony. The third morphotype is considered a large ornithopod footprint belonging to the ichnofamily Iguanodontipodidae. This ichnofamily is typical for Cretaceous tracksites but the new material suggests that it might also be present in the Late Jurassic. The three morphotypes show a negative correlation between size and mesaxony, so the smaller tracks show the stronger mesaxony, and the larger ones weaker mesaxony. The Upper Jurassic ornithopod record from the Lusitanian Basin has yielded both small and medium-sized ornithopod remains, mainly iguanodontians such as dryosaurids and ankylopollexians, which are the main candidates to be the trackmakers.

The upper Cenomanian and basal Turonian ammonite assemblages of the West Portuguese Carbonate Platform (WPCP) are characterised by the occurrence of many Tethyan species, with emphasis on Vascoceratidae. They include Vascoceras gamai , type-species of the genus, and several other taxa created in 1898, by Choffat, based on abundant materials collected from exposures of the Baixo Mondego region (West Central Portugal), in the northern range of the carbonate platform. As noted by Berthou et al., in 1975 and subsequent works, many of these Vascoceras are upper Cenomanian and form two distinct assemblages, respectively with Euomphaloceras septemseriatus and Pseudaspidoceras pseudonodosoides . The occurrence of this latter species can be correlated with the uppermost Cenomanian Neocardioceras juddii standard zone, since both species co-occur in assemblages with vascoceratid ammonites described by Cobban et al. (1989) in New Mexico (United States). It is precisely from the same assemblages that the genus Rubroceras was originally described, as an interesting example of the late Cenomanian evolutionary diversification of the Vascoceratidae, when highly ornamented forms with transverse ribs persisting in the body chamber appeared in Tethyan assemblages with Vascoceras , characterised by much more smooth morphologies. As in New Mexico, the occurrence of Rubroceras in the WPCP is restricted to a stratigraphic unit with Pseudaspidoceras pseudonodosoides , Vascoceras gamai , V. barcoicense and V. silvanense . Besides Rubroceras alatum and R . burroense , other additional taxa are Spatithes ( Jeanrogericeras ) subconciliatus , Vascoceras adonense , Vascoceras sp. A and Parapuzosia ( Austiniceras ) sp. This assemblage mostly occurs in the outcrops of Nossa Senhora dos Olivais, near Tentugal, in the northern range of the carbonate platform. It is found above beds with Euomphaloceras septemseriatus and Vascoceras gamai , and below the highest upper Cenomanian unit of the area, with P . pseudonodosoides , Spatithes ( Jeanrogericeras ) subconciliatus , Fagesia catinus , and depressed Vascoceras , such as V . durandi , V . douvillei and V . kossmati . In addition to New Mexico and West Portugal, representatives of Rubroceras are presently known from other carbonate platforms of North Africa, Arabian Peninsula and Nigeria, where they have been found in ammonite assemblages correlative to the Neocardioceras juddii standard zone. They are apparently absent from the remaining basins of the Iberian microplate with abundance of Vascoceratidae representatives, namely the Iberian Through (Spain), whose late Cenomanian oceanic communication was more processed from the North. Further studies will provide a better understanding of this important biotic dispersal event across the Tethyan Realm, as an additional marker of uppermost Cenomanian ammonite assemblages.

A new Upper Cretaceous vertebrate tracksite has been discovered at Tamajon (Iberian Ranges, Guadalajara, Spain). The track level is a relatively smooth and slightly undulating sandy ferruginous crust, corresponding to an erosive surface at the base of a small meandering channel. It is incised into the underlying planar cross-bedded sandstones of coastal bars located at the middle-upper part of the Utrillas Formation (middle-upper Cenomanian). The site shows an extraordinary concentration of vertebrate tracks, among which numerous sets of two to five isolated digit impressions (“swim tracks”) and, at least, two trackways referred to crocodyliforms, and a single tridactyl footprint probably produced by a theropod dinosaur can be recognized. There are also several long traces (epichnial grooves) revealing sharp direction changes (up to 90°) which seem to be fish fin traces ( Undichna unisulca ), although crocodyliforms (tail marks) and/or fish invertebrates cannot be rejected as possible tracemakers. Some crocodyliform tracks reveal a thin raised rim, due to the displacement of the sediment by the pressure produced by the feet. Several impressions are moderately deformed by small sediment slides, only preserving their deepest part (claw marks). This is clearly indicative of a soft substrate with a high degree of plasticity and water content at the time of the track registration. Nevertheless, the sediment was hard enough to preserve manus and pes print morphologies and also possible crocodyliform tail and/or fish fin traces. Small rhizoliths can also be recognized and may belong to herbaceous wetland vegetation. The morphology of the palaeochannel, the sedimentary context and the track preservation seem to indicate that the tracks were impressed in a shallow channel located near the coast, under wet conditions and in different moments of time. This discovery represents the first occurrence of vertebrate ichnites in the Utrillas Formation, a stratigraphic unit where osteological and ichnological remains are relatively scarce, and it confirms that some crocodyliforms lived in near coast channels during the deposition of this unit.

The palaeontological sites of Riba de Santiuste and Sienes (Riba de Santiuste area) are located in the province of Guadalajara, Spain. They include a stratigraphic interval in Muschelkalk facies belonging to the “Cuesta del Castillo Sandstones” Formation and “Royuela Dolostones, Marls and Mudstones” Formation. These sites include numerous fossil plants, direct vertebrate remains, and vertebrate swim traces. The vertebrate remains correspond to a multitude of anatomical elements of Sauropterygia (Nothosauroidea, Placodontia) and possible Archosauria (Rauisuchia) remains. The fossil material attributed to nothosaurs includes teeth, coracoids, a thoracic vertebra, some isolated vertebral centra, humerus, rib fragments, and some dorsal and caudal vertebrae. The remains attributed to placodonts correspond to fragments of skull, quadrate, teeth and osteoderms. Other undetermined sauropterygian remains, such as ulnas, fragments of long bones, fragments of ribs, and articular facets of ribs have been also recovered. Additionally, a fragment of mandible and an intervertebral disk of indeterminate reptiles whose size could be compatible with archosaurs are also described. These bones are exceptionally well-preserved because the fossilization processes have preserved the microstructure of the tissues. The sites also show vertebrate traces, with parallel scratch impressions interpreted as swim traces. The relative stratigraphic position and the palaeontological content of these sites suggest a Ladinian age (Middle Triassic). The interpretation of the sedimentary facies here described also suggests that the sites could correspond to detrital-carbonate mixed deposits of coastal intertidal to supratidal environments. This work is developed within Predoctoral Research Training Grant CT45/15-CT46/15 from the UCM, and is a contribution to Research Projects CGL2015-66604 and CGL2015-68363 from the Spanish Ministerio de Economía y Competitividad (Economy and Competitiveness Ministry).

UID/HIS/04209/2013 A shell coming from an upper Oxfordian section of the Lusitanian Basin located in Alqueidão da Serra (Municipality of Porto de Mós, West Central Portugal) is here presented. It corresponds to the oldest remain of a turtle identified in Portugal. In fact, the record of Jurassic turtles identified in pre-Kimmeridgian levels of Europe is very scarce. The new specimen represents the second worldwide identification of a Plesiochelyid turtle (basal Eucryptodira) performed in pre-Kimmeridgian levels, being the only one recognized at generic level. Therefore, this specimen corresponds to the oldest identification of Craspedochelys, a genus well-represented in Kimmeridgian and Tithonian levels of several European countries. This finding contributes the first evidence on the synchronous coexistence of more than a member of Plesiochelyidae in pre-Kimmeridgian levels, which provides arguments to justify the relatively wide diversity known for this exclusively Jurassic clade during the Kimmeridgian and the Tithonian. authorsversion published

Late Jurassic theropod tracks are very common both in North Africa and Europe. Two recently described ichnotaxa Megalosauripus transjuranicus and Jurabrontes curtedulensis from the Kimmeridgian of Switzerland show the coexistence of two apex predators in the same palaeoenvironment. Similar tracks can be found in tracksites from the Iberian Peninsula and from Morocco. Here, we further explore the similarities among the Swiss ichnotaxa and the other tracks from Germany (Kimmeridgian), Spain (Tithonian-Berriasian), Portugal (Oxfordian-Tithonian) and Morocco (Kimmeridgian) through novel three-dimensional data comparisons. Specimens were grouped in two morphotypes: 1) large and gracile (30 50 cm). The analyses show a great morphological overlap among these two morphotypes and the Swiss ichnotaxa (Megalosauripus transjuranicus and Jurabrontes curtedulensis, respectively), even despite the differences in sedimentary environment and age. This suggests a widespread occurrence of similar ichnotaxa along the western margin of Tethys during the Late Jurassic. The new data support the hypothesis of a Gondwana-Laurasia faunal exchange during the Middle or early Late Jurassic, and the presence of migratory routes around the Tethys.

Fieldwork carried out during the past few years in the Algarve region (Portugal) has allowed the description of dinosaur tracks for the first time in the Mesozoic Algarve Basin. Five track levels of Early Barremian age have been described from the Santa and Salema tracksites situated near Vila do Bispo (southwest Algarve). These comprise theropod and iguanodontian footprints (Iguanodontipus isp. was identified at the Santa tracksite). A sequence of subcircular and tridactyl impressions with a characteristic morphology of ornithopod footprints with a high pace angulation value made it possible to determine how erosion changes the print morphology and to understand the sequences of subcircular impressions with a high value of pace angulation in the track record. These dinosaur footprints are preserved in marginal-marine carbonate sediments of a large inner shelf palaeoenvironment with shoals and tidal-flat areas that were periodically exposed. The warm and dry climate favoured extensive growth of algal mats and the deposition of dolomitic sediments. The discovery of these track levels has also enabled the palaeobiogeographical data available for the Early Cretaceous Iguanodontia of the Iberian Peninsula and southwestern Europe to be refined.

A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal)preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late Jurassic-Early Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes.

The study in course of the materials rescued from the fire that in 1978, destroyed much of the palaeontological collections of the current National Museum of Natural History and Science (Museu Nacional de Historia Natural e da Ciencia) of Lisbon, has allowed the rediscovery of several Cretaceous cephalopods (and the corresponding original labels) that the renowned palaeontologist Alcide d'Orbigny, according to the wishes of the emperor Napoleon III, offered to the king Pedro V in 1855, in order to re-establish the good relationships between France and Portugal. These historical specimens correspond to nautiloids: Angulithes triangularisde Montfort, 1808; ammonoids: Phylloceras (Hypophylloceras) tethys (d'Orbigny, 1840), Ptychophylloceras (Semisulcatoceras) semisulcatum (d'Orbigny, 1840), Neolissoceras grasianum (d'Orbigny, 1840), Pleurohoplites (Pleurohoplites) renauxianus (d'Orbigny, 1840), Acanthoceras rhotomagense (Brongniart, 1822), Coilopoceras requienianus (d'Orbigny, 1840) and Turrilites (Turrilites) costatusLamarck, 1801; and belemnoids: Duvalia dilatata (de Blainville, 1827), Hibolithes subfusiformis (Raspail, 1829) and Belemnitella mucronata (von Schlotheim, 1813). All of them come from outcrops relevant for the French stratigraphy, and they seem to have been selected by d'Orbigny with a representative criterion.

The Galinha tracksite reveals a sequence of Bajocian—Bathonian limestones belonging to the Serra de Aire Formation (West-Central Portugal) and is one of the few sites in the world where Middle Jurassic sauropod dinosaur tracks can be found. This tracksite is characterised by the presence of long, wide gauge sauropod trackways, the Middle Jurassic age of which suggests these dinosaurs were more widely distributed over time than previously thought. Two trackways contain unique pes and manus prints with morphologies that allow a new sauropod ichnotaxon to be described: Polyonyx gomesi igen, et isp. nov. On the basis of different manus/pes prints and trackway features, the proposal is made to subdivide Sauropodomorpha ichno-morphotypes into five groups: Tetrasauropus-like, Otozoum-like, Breviparopus/Parabrontopodus-like; Brontopodus-like, and Polyonyx-like. Polyonyx gomesi igen, et isp. nov. is thought to represent a non-neosauropod eusauropod, with a well developed manus digit I. The posterior orientation of...

A recently discovered Early Cretaceous (early late Albian) dinosaur tracksite at Parede beach (Cascais, Portugal) reveals evidence of dinoturbation and at least two sauropod trackways. One of these trackways can be classified as narrow-gauge, which represents unique evidence in the Albian of the Iberian Peninsula and provides for the improvement of knowledge of this kind of trackway and its probable trackmaker, in an age when the sauropod record is scarce. These dinosaur tracks are preserved on the upper surface of a marly limestone bed that belongs to the Gale Formation (Agua Doce Member, middle to lower upper Albian). The study of thin-sections of the beds C22/24 and C26 in the Parede section has revealed a microfacies composed of foraminifers, radiolarians, ostracods, corals, bivalves, gastropods, and echinoids in a mainly wackestone texture with biomicritic matrix. These assemblages match with the lithofacies, marine molluscs, echinids, and ichnofossils sampled from the section and indicate a shallow marine, inner shelf palaeoenvironment with a shallowing-upward trend. The biofacies and the sequence analysis are compatible with the early late Albian age attributed to the tracksite. These tracks and the moderate dinoturbation index indicate sauropod activity in this palaeoenvironment. Titanosaurs can be dismissed as possible trackmakers on the basis of the narrow-gauge trackway, and probably by the kidney-shaped manus morphology and the pes-dominated configuration of the trackway. Narrow-gauge sauropod trackways have been positively associated with coastal palaeoenvironments, and the Parede tracksite supports this interpretation. In addition, this tracksite adds new data about the presence of sauropod pes-dominated trackways in cohesive substrates. As the Portuguese Cretaceous sauropod osteological remains are very scarce, the Parede tracksite yields new and relevant evidence of these dinosaurs. Furthermore, the Parede tracksite is the youngest evidence of sauropods in the Portuguese record and some of the rare evidence of sauropods in Europe during the Albian. This discovery enhances the palaeobiological data for the Early Cretaceous Sauropoda of the Iberian Peninsula, where the osteological remains of these dinosaurs are relatively scarce in this region of southwestern Europe. Therefore, this occurrence is also of overall interest due to its impact on Cretaceous Sauropoda palaeobiogeography.

The historical holotypes of the Cenomanian (Upper Cretaceous) ammonites Vascoceras gamai Choffat, 1898 (type of the genus), and Vascoceras barcoicense (Choffat, 1898), thought to be destroyed by the fire of March 1978 at the National Museum of Natural History, Lisbon, Portugal, have been rediscovered in good state of preservation. Based on the study of the originals, these upper Cenomanian specimens can be rehabilitated as holotypes, maintaining and justifying the status of both taxa as well as of Vascoceras cauvini Chudeau, 1909.

More than a hundred sauropod tracksites, ranging in age from Middle Jurassic (Bathonian) to Late Cretaceous (Maastrichtian), are repor­ted from the Iberian Peninsula (Spain and Portugal). Sauropod trackway orientation patterns throughout an entire geographic area such as the Iberian Peninsula and over different time periods may provide new data about the palaeoecology and behavioural patterns of sauropods. The studied tracksites exhibit two main trackway orientation patterns, directional and random, indicating different behaviours in grega­rious or solitary (milling) individuals. Gregarious behavioural patterns are mainly observed within Parabrontopodus/Breviparopus- like and Brontopodus -like ichnotypes of a single size class (either small or medium-sized), indicating age segregation. Among the gregarious sauropods the former ichnotype is linked with inland environments, while the latter is mainly linked with coastal environments. Solitary trackways are mainly of medium-sized to large individuals, are also linked with both inland ( Parabrontopodus/Breviparopus -like) and coastal environments ( Parabrontopodus/Breviparopus -like, Brontopodus -like), and belong to the above-mentioned ichnotypes as well as to Polyonyx -like ichnotypes. Thus, no obvious link between gregarious behaviour and the palaeoenvironmental setting can be inferred from the sauropod track record of the Iberian Peninsula. Nonetheless, sauropod trackways showing titanosauriform characters ( Brontopodus -like) are more common in coastal environments, contrary to what might be expected given this group’s apparent taxonomic preference for inland environments.

Large semicircular traces and markings that resemble tracks made by horses or mules wearing horseshoes, have been a source of much confusion in the paleontological literature. Study of these traces has followed a convoluted trail from thirteenth century Portuguese folklore to purported Deinonychus tracks in Uzbekistan and China, to creationist preachings in North America. We show that these traces or markings, which occur in many Phanerozoic deposits, but especially in the Mesozoic, are in most cases examples of the well known burrow Rhizocorallium, or examples of current crescents. Although these traces do bear a remarkable resemblance to tracks made by mules or horses (wearing “horseshoes"), such interpretations are obviously out of the question, for pre‐Cenozoic deposits, even though they have provided fuel for creationists. We herein show that the enigmatic trace fossil Gumatagichnus ungliformis from the Cenomanian of Uzbekistan is a Rhizocorallium burrow of invertebrate, not vertebrate, origin. Simil...

Geometric morphometrics are used to characterize shape variations in different Sauropodomorpha ichnotaxa and unclassified ichnites. Ten landmarks were collected from each of 30 specimens. Landmark configurations were superimposed, and residuals were modeled with the thin-plate spline interpolating function (to visualize shape changes). This group of techniques allows to discriminate tendencies in shape changes (providing quantitative descriptors). The multivariate analysis of shape variables on the centroid size indicates the absence of allometry in our sample of Sauropodomorpha tracks.