José Ignacio Canudo

A New Sauropod: Tastavinsaurus Sanzi Gen. Et Sp. Nov. from the Early Cretaceous (Aptian) of Spain

Abstract The new sauropod dinosaur Tastavinsaurus sanzi, gen. et sp. nov., from the early Aptian of Spain is described. The holotype is a partially articulated skeleton of an adult individual recovered from the Arsis-1 site in Peñarroya de Tastavins (Teruel) at the base of the marine Xert Formation. It is one of the most complete and best-preserved sauropod dinosaur skeletons from the European Early Cretaceous. The fossil remains comprise the three caudalmost thoracic vertebrae, part of a fourth, nine thoracic rib fragments, sacrum, 25 caudal vertebrae, 21 chevrons, both ilia, pubes, ischia and femora, right tibia, right fibula, six metatarsals, and seven pedal phalanges (including four unguals). The new taxon is defined by 19 autapomorphies. In our cladistic analysis, Tastavinsaurus is the sister-taxon of the North American Venenosaurus within Titanosauriformes, which includes the Brachiosauridae, Somphospondyli, and Titanosauria. The new taxon provides new information about the diversity of non-brachiosaurid titanosauriforms during the Early Cretaceous in Europe and paleobiogeographic relationships between Europe and North America.

La séquence des rongeurs (Mammalia) des sites du Pléistocène inférieur et moyen d'Atapuerca (Burgos, Espagne)

The Rodent sequence (Mammalia) of the Lower to Middle Pleistocene sites of Atapuerca (Burgos, Spain). The Sierra the Atapuerca has several Early to Middle Pleistocene localities related with a karst system. A railway trench exposes some of the cave deposits that have an excellent record of fossil humans, large and small mammals and other vertebrates, as well as an important Lithic industry of Modes 1 to 3. Some of these caves are: Trinchera Dolina, Trinchera Galeria, Trinchera Elefante and Sima de los Huesos. In this paper we expose our results obtained from the study of the small mammals from the Atapuerca sites. The Gran Dolina or Trinchera Dolina is stratigraphically the longest sequence (18m), and it is divided in 11 stratigraphical levels, from bottom TD1, to top TD11. They belong to different chronological periods of Early and Middle Pleistocene age. The uppermost levels of Gran Dolina (TD11, TD10 and TD8b) contain Middle Pleistocene (post-Cromerian) micromammal assemblages: Arvicola, diverse and modern Microtus Terricola species, and Pliomys lenki. The lowermost levels (TD3 to TD6) contain late Early to early Middle Pleistocene mammals: Allophaiomys, Mimomys savini, primitive Microtus, Stenocranius, Terricola and, Pliomys episcopalis species. TD8a contains a scarce association of wet and open country faunas as Microtus related to the M. cf. oeconomus-ratticepoides. The level TD7 (between TD 6 and TD8a), records the Matuyama/Brunhes paleomagnetic reversal, and it has few fossil remains. Levels TD1, 2 and 9 are sterile in fossil contents. The level TD6 has record one of the earliest Homo species of Europe: Homo antecessor. The Trinchera Galeria complex has been divided into five clastic fill phases (GI to GV) with twelve human living floors (GSU1-12) and it have yielded also human remains. The lower levels represent a more intense occupation of the cave by humans, yielding many stone tools and herbivore bones. Rodents from this site are characteristic of the Middle Pleistocene, (11 species): Arvicola aff. sapidus, Microtus jansoni, Microtus aff. arvalis, Terricola atapuerquensis, Iberomys brecciensis, Pliomys lenki, Allocricetus bursae, Apodemus sp., Eliomys quercinus quercinus, Marmota sp., Hystrix (Acanthion) vinogradovi. The Trinchera Elefante red lower unit has some rodents in common to the lower levels of Trinchera Dolina (TD3–TD6) as Allophaiomys chalinei, Iberomys huescarensis, Pliomys episcopalis and some of them are new to the Atapuerca record of small mammals : Ungaromys nanus, Castillomys rivas, Eliomys sp., Mimomys sp. and Allophaiomys lavocati. Small mammals from the upper units are still under study. The Sima de los Huesos site, well known by the well preserved, anatomically complete association of fossil human remains of Homo heidelbergensis, has very few fossils of small vertebrates: Allocricetus bursae; Apodemus sylvaticus; Pliomys lenki relictus; Microtinae indet.; Eliomys quercinus., the cave bats Rhinolophus mehelyi; Myotis myotis/M. blythi and Miniopterus schreibersi; some insectivores belonging to the genus Crocidura sp., some fish vertebrae and teeth (Salmo sp. and Leuciscus sp.) and undetermined small reptile bones. Fragments of gasteropods, arthropods, charophytes and plant remains are also present.

Discriminating between Medium-Sized Tridactyl Trackmakers: Tracking Ornithopod Tracks in the Base of the Cretaceous (Berriasian, Spain)

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 length-width 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.

A New Crocodylian from the Late Maastrichtian of Spain: Implications for the Initial Radiation of Crocodyloids

Background The earliest crocodylians are known primarily from the Late Cretaceous of North America and Europe. The representatives of Gavialoidea and Alligatoroidea are known in the Late Cretaceous of both continents, yet the biogeographic origins of Crocodyloidea are poorly understood. Up to now, only one representative of this clade has been known from the Late Cretaceous, the basal crocodyloid Prodiplocynodon from the Maastrichtian of North America. Methodology/Principal Findings The fossil studied is a skull collected from sandstones in the lower part of the Tremp Formation, in Chron C30n, dated at −67.6 to 65.5 Ma (late Maastrichtian), in Arén (Huesca, Spain). It is located in a continuous section that contains the K/P boundary, in which the dinosaur faunas closest to the K/P boundary in Europe have been described, including Arenysaurus ardevoli and Blasisaurus canudoi. Phylogenetic analysis places the new taxon, Arenysuchus gascabadiolorum, at the base of Crocodyloidea. Conclusions/Significance The new taxon is the oldest crocodyloid representative in Eurasia. Crocodyloidea had previously only been known from the Palaeogene onwards in this part of Laurasia. Phylogenetically, Arenysuchus gascabadiolorum is situated at the base of the first radiation of crocodyloids that occurred in the late Maastrichtian, shedding light on this part of the cladogram. The presence of basal crocodyloids at the end of the Cretaceous both in North America and Europe provides new evidence of the faunal exchange via the Thulean Land Bridge during the Maastrichtian.

La Cantalera: an exceptional window onto the vertebrate biodiversity of the Hauterivian-Barremian transition in the Iberian Peninsula

La Cantalera is an accumulation site for fossil vertebrates consisting mainly of teeth and isolated postcranial remains. It has the greatest vertebrate biodiversity of any site from the Hauterivian-Barremian transition in the Iberian Peninsula. Up to now, 31 vertebrate taxa have been recognized: an osteichthyan (Teleostei indet.), two amphibians (Albanerpetonidae indet. and Discoglossidae indet.), a chelonian (Pleurosternidae? indet.), a lizard (Paramacellodidae? indet.), four crocodylomorphs (cf. Theriosuchus sp., Bernissartiidae indet., Goniopholididae indet., cf. Lisboasaurus sp.), two pterosaurs (Istiodactylidae? indet., Ornithocheiridae? indet.), four ornithopod dinosaurs (Iguanodontoidea indet., Hadrosauroidea? indet., “Hypsilophodontidae” indet., Rhabdodontidae? indet.), a thyreophoran (Polacanthidae indet.), a sauropod (Euhelopodidae indet.), eleven theropods (Carcharodontosauridae? indet., Baryonychinae indet., aff. Paronychodon sp., Maniraptora indet. 1-3, Dromaeosaurinae indet. 1-3, Velociraptorinae indet., Avialae? indet.) and three or four multituberculate mammals (Cantalera abadi, Eobaatar sp., Plagiaulacidae or Eobaataridae gen. et sp. indet., “Plagiaulacida” indet.). Nine ootaxa have also been distinguished at the site of La Cantalera. Oofamilies assigned to dinosaurs (Elongaloolithidae, Prismatoolithidae, cf. Spheroolithidae), to crocodiles (Krokolithidae) and eggshells of two oofamilies incertidae sedis are represented. This association is consistent with the record of bone and tooth remains from the site. La Cantalera was formed in a marshy environment where there was an intermittent body of water. The great majority of the vertebrate fossil remains lack evidence of transport, so the preserved association is a good representation of the vertebrate ecosystem in or around the marshy area of La Cantalera. The vertebrate association of La Cantalera displays certain differences with respect to those from lacustrine environments of the Hauterivian-Barremian transition of the Iberian Range. These differences include, for example, the absence of Chondrichthyes, the merely token presence of the osteichthyans, the scarcity of chelonians, the presence of exclusively multituberculate mammals, the lower diversity of sauropods and the greater diversity of theropods.

The eusuchian crocodylomorph Allodaposuchus subjuniperus sp. nov., a new species from the latest Cretaceous (upper Maastrichtian) of Spain

This paper describes the skull of the eusuchian Allodaposuchus subjuniperus sp. nov. This new skull was recovered between the villages of Beranuy and Serraduy del Pon (Huesca, Spain). Stratigraphically, it was located in a level of coarse-grained sandstones in the middle-upper part of the lower red unit (Conqués Formation) of the Tremp Group, in the uppermost Maastrichtian close to the Cretaceous–Paleogene boundary. Until now Allodaposuchus was a monospecific genus. Phylogenetic analysis places the new taxon as a basal member of Eusuchia forming a clade with the other European Allodaposuchus remains and as a sister clade to the endemic European members of Hylaeochampsidae. Furthermore, Allodaposuchus and Hylaeochampsidae are within the stem of Crocodylia, being key taxa to understanding the origin of Crocodylia. The new taxon is the latest record of Allodaposuchus from Europe, and it presents significant enough morphological differences from Allodaposuchus precedens to establish a new species. The morphological variations in the material included in Allodaposuchus, the wide range of age and the geographical separation among the remains from Romania, France and Spain indicate that Allodaposuchus is not a monospecific genus as traditionally established.http://zoobank.org/96CCE2FE-531A-4479-BE54-172D589D16A0

A new sauropod titanosaur from the Plottier Formation (Upper Cretaceous) of Patagonia (Argentina)

This paper presents a new titanosaur sauropod, collected from levels of reddish clays assigned to the Plottier Formation (Coniacian-Santonian). The holotype of Petrobrasaurus puestohernandezi gen. et. sp. nov. is a disarticulated specimen, from which teeth, cervical, dorsal and caudal vertebrae, sternal plates, metacarpals, femora, tibia, a fragment of ilium, pubis, haemal arches, and cervical and dorsal ribs have been preserved. This period is of particular interest because it saw the definitive isolation of the vertebrate faunas of Patagonia, with the separation of South America from the rest of Gondwana, a process that had begun during the Early Cretaceous. Although some of the characters observed in Petrobrasaurus gen. nov. suggest a relationship with the South American clade Lognkosauria, this new sauropod is regarded as Titanosauria incertae sedis until a more profound analysis of the Titanosauria that in which it is included is undertaken.

The Latest Succession of Dinosaur Tracksites in Europe: Hadrosaur Ichnology, Track Production and Palaeoenvironments

A comprehensive review and study of the rich dinosaur track record of the Tremp Formation in the southern Pyrenees of Spain (Southwestern Europe) shows a unique succession of footprint localities prior to the end-Cretaceous mass extinction event. A description of some 30 new tracksites and data on sedimentary environments, track occurrence and preservation, ichnology and chronostratigraphy are provided. These new track localities represent various facies types within a diverse set of fluvial environments. The footprint discoveries mostly represent hadrosaurian and, less abundantly, to sauropod dinosaurs. The hadrosaur tracks are significantly smaller in size than, but morphologically similar to, those of North America and Asia and are attributable to the ichnogenus Hadrosauropodus. The track succession, with more than 40 distinct track levels, indicates that hadrosaur footprints in the Ibero-Armorican region occur predominantly in the late Maaastrichtian (at least above the early Maastrichtian–late Maastrichtian boundary). The highest abundance is found noticeably found in the late Maastrichtian, with tracks occurring in the C29r magnetochron, within about the latest 300,000 years of the Cretaceous.

Manus track preservation bias as a key factor for assessing trackmaker identity and quadrupedalism in basal ornithopods.

Background The Las Cerradicas site (Tithonian–Berriasian), Teruel, Spain, preserves at least seventeen dinosaur trackways, some of them formerly attributed to quadrupedal ornithopods, sauropods and theropods. The exposure of new track evidence allows a more detailed interpretation of the controversial tridactyl trackways as well as the modes of locomotion and taxonomic affinities of the trackmakers. Methodology/Principal Findings Detailed stratigraphic analysis reveals four different levels where footprints have been preserved in different modes. Within the tridactyl trackways, manus tracks are mainly present in a specific horizon relative to surface tracks. The presence of manus tracks is interpreted as evidence of an ornithopod trackmaker. Cross-sections produced from photogrammetric digital models show different depths of the pes and manus, suggesting covariance in loading between the forelimbs and the hindlimbs. Conclusions/Significance Several features (digital pads, length/width ratio, claw marks) of some ornithopod pes tracks from Las Cerradicas are reminiscent of theropod pedal morphology. This morphological convergence, combined with the shallow nature of the manus tracks, which reduces preservation potential, opens a new window into the interpretation of these tridactyl tracks. Thus, trackmaker assignations during the Jurassic–Cretaceous interval of purported theropod trackways may potentially represent ornithopods. Moreover, the Las Cerradicas trackways are further evidence for quadrupedalism among some basal small- to medium-sized ornithopods from this time interval.

El Kef blind test I results

Samples were disaggregated in water. Each sample was then cleaned with ultrasonic agitation for 10 to 15 s and washed through a 63-pm screen. The procedure was repeated until a clean foraminiferal residue was recovered from the screen. The final residue was dried in an oven at 50°C. Population counts were made from representative splits (using an Otto microsplitter) of 300-400 specimens from the >63+m size fraction. The sample 15-20 cm below the K/T boundary was contaminated in the laboratory. For this reason, it was not included in the analysis. The sample counts and species identified are listed in Tables 1 and 2.