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Dinosaur fossils are becoming increasingly well-known from the Bauru Basin of Brazil, and represent some of the last occurring dinosaurs in South America before the end-Cretaceous mass extinction. However, sampling across the basin is not uniform, and comparatively little is known about the fossils from the northern part of the basin. Our fieldwork team discovered two isolated and well-preserved ziphodont theropod teeth from northern basin strata of the Maastrichtian Marília Formation of the south of the state of Goiás. We here identify them using quantitative analysis of morphometric data and comparisons to teeth previously described in the literature. Our comparisons and analyses indicate that they can be assigned to Abelisauridae. These specimens have little evident crown enamel ornamentation, a characteristic widely present in the teeth of theropods from the Southern Hemisphere. The materials described here are the northernmost Bauru Basin abelisaurids reported so far, demonstrating that these carnivorous dinosaurs were important faunal components across the extent of the basin, as they were in other regions of South America. • This study presents a first Abelisauridae records from the from state of Goiás of Late Cretaceous Bauru Group. • The Upper Cretaceous Abelisauridae from South America were expanded into a new area. [ABSTRACT FROM AUTHOR]

Ichnofossils are a useful tool in determining some aspects of the palaeoecology from past ecosystems, being often used as evidence of interactions between extinct organisms. In this paper we describe tooth traces found in UFRJ-DG 705 R, a fragmentary sauropod epiphysis, from the Presidente Prudente Formation, Bauru Group. We infer that these traces were made by a small to medium-sized crocodyliform, most likely an itasuchid, in a possible act of necrophagy. This new record of tooth traces in the Bauru Group showcases important evidence concerning trophic relations between sauropods and crocodyliforms in this locality during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

The description of new titanosaur specimens unearthed from deposits of the Serra da Galga Formation (Bauru Group, Late Cretaceous) at the BR-262 site, near Peirópolis (Uberaba, Minas Gerais State, Brazil), sheds light on the taxonomy of two taxa previously known from the same area and geological unit: Baurutitan britoi and Trigonosaurus pricei. A comparative revision indicates that T. pricei represents a junior synonym of Ba. britoi, and that the BR-262 specimens belong to that latter species. The information provided by the new specimens also revealed that the paratype of T. pricei (MCT 1719-R), a caudal vertebral series, actually represents a new taxon, named here as Caieiria allocaudata gen. et sp. nov. [ABSTRACT FROM AUTHOR]

Pterosaurs are powered flight vertebrates that first emerged in the Late Triassic and persisted until the end of the Cretaceous. Recent studies on the ecological niches and habitats of pterosaurs, based on discoveries of Cretaceous bone beds in China, Brazil, Morocco, and other locations, suggest a decline in pterosaur diversity during the mid-Cretaceous. Various hypotheses have been proposed to interpret this phenomenon. This study focuses on newly discovered pterosaur tracks at the Upper Cretaceous (Truonian) Hwasun Seoyuri tracksite in Korea. The analysis is based on pterosaur tracks from in situ and ex situ specimens that originate from a variety of stratigraphic levels. The evidence found suggests that the Hwasun Seoyuri tracksite was occupied by small pterosaurs over an extended period, with indications of recurrent activity across at least six levels. Furthermore, the footprint sizes observed across these multiple layers follow a non-skewed normal distribution. Considering the known logarithmic growth characteristics of pterosaurs, this result suggests a predominantly immature population at this site. The prevalence of mid-Cretaceous non-marine pterosaur tracksites on the Korean Peninsula may reflect broader ecological shifts for pterosaurs during this period. This evidence is considered alongside the habitat shifts suggested by other non-marine pterosaur fossil sites in China and Brazil, as well as with indications of the decline in Late Cretaceous non-marine basins. • New pterosaur tracks were found in the Late Cretaceous of Hwasun Seoyuri in Korea. • The trackmaker may be young or small azhdarchid or unknown taxa. • The track size distribution suggests immature pterosaur gregariousness. • The decrease in late Cretaceous pterosaurs could be linked to habitat shift. [ABSTRACT FROM AUTHOR]

Aeolosaurus is a late Cretaceous Titanosaur genus with two species discovered in Argentina and one in Brazil. Although the allocation of the Argentinean Aeolosaurus seems unequivocal, that is not the case for the Brazilian species Aeolosaurus maximus since several authors questioned its positioning into this genus, based on both anatomical and phylogenetic data. The revision of the diagnosis of Ae. maximus, with the proposition of a new autapomorphy, corroborates the anatomical uniqueness and our phylogenetic analysis stresses that the relation of Ae. maximus to the Argentinean Aeolosaurus is uncertain. Based upon that, we propose a new genus, Arrudatitan, to accommodate the Brazilian taxon. [ABSTRACT FROM AUTHOR]

The southern Goiás state region of Central Brazil has an extensive and informative record of fossil biota. Particularly over the last five years, there has been a great increase in fossil finds, which has enabled a greater understanding of this region's fauna and flora during the Late Cretaceous. In this article, we provide an updated synthesis of the biota from the Cretaceous of the southern Goiás state, the record of plants, gastropods, turtles, crocodilians, titanosaurs, and theropod dinosaurs. [ABSTRACT FROM AUTHOR]

A fossil spine, originally described as belonging to Perciformes from the Late Cretaceous Marilia Formation, Bauru Basin, Southeastern Brazil, is here restudied based on paleohistology. In addition to the overall morphology of the spine, our histological results point to the presence of pseudolamellar bone with embedded star-shaped osteocytes. These results confirm the recent redescription of this specimen as a Siluriformes, and confirm the absence, so far, of Percomorpha in freshwater deposits from the Cretaceous of Brazil and South America. [ABSTRACT FROM AUTHOR]

This work presents the first record of bony fish from the Maastrichtian of the Marília Formation (Bauru Group) in Goiás State, Brazil. A fragment of a pectoral spine, recovered by screen-washing, clearly represents an important catfish (Siluriformes) record from the Late Cretaceous of South America. The material possesses similarities with forms from the Campanian - early-Maastrichtian of the Adamantina Formation and the Maastrichtian of the Marília (São Paulo State) and El Molino (Bolivia) formations. Inclusion of the new material from Goiás in the dataset for the aforementioned areas within a paleoenvironmental setting provides evidence that Late Cretaceous catfish had a wider distribution than previously known. • This study describes first fish record from Late Cretaceous Bauru Group in Goiás state, Brazil. • The Upper Cretaceous paleogeographical and paleoenvironments from South American catfish were updates. • An overview of records of siluriformes from the Cretaceous of South America were presented. [ABSTRACT FROM AUTHOR]

The Late Cretaceous Marília Formation located in the central-southern portion of Brazil is characterized by a succession of sandstones, conglomerates, and paleosols. The paleosols constitute more than 60% of this formation, providing significant information about pedogenetic processes as well as paleoenvironmental and paleoclimate implications. The paleosols of the Marília Formation have been studied principally from a stratigraphical, sedimentological and paleopedological point of view; however, there are no studies addressing in detail the geochemical behavior of the paleosols. Therefore, we used a robust geochemical dataset combined with stratigraphical and macromorphological interpretations as well as clay mineralogy to conduct a paleoenvironmental and paleoclimate analysis of the Marília Formation in the western portion of the state of Minas Gerais in Brazil. The results indicate that the paleosols of the Marília Formation can be divided into three pedotypes and pedochemical units based on their geochemical variations and are limited at the base and top by pedochemical markers. Moreover, X-ray diffraction identified quartz and calcite as primary minerals associated with montmorillonite, smectite, illite and palygorskite, indicating wet periods combined with dry stages associated principally with dry and arid environments. The paleosol distribution and weathering index allow us to interpret the paleoenvironmental evolution of the Late Cretaceous Marília Formation, suggesting an increase in humidity from east to west in the study area. • A new approach using pedochemistry analysis was used. • Three pedochemical units and geochemical markers were identified. • Seasonal variations based on weathering indexes were observed. • Paleoenvironmental and paleoclimate conditions indicate arid to semiarid climate. [ABSTRACT FROM AUTHOR]

Substantial magmatism occurred during the development of the marginal basins of the central and southern South Atlantic. Situated on the Brazilian side of the central segment, the Campos and Santos basin represent a transitional margin, located between the magma-rich margin in the north and the magma-poor margin in the south. In addition to magmatism associated with the initiation of continental rifting, the southeast Brazilian basins experienced three main magmatic events; one during the early post-rift (i.e., sag stage) and two during the late post-rift (i.e., passive margin stage), both occurring after deposition of a thick, late Aptian salt layer. The products of post-salt, intrusive and extrusive magmatism in the southern Campos Basin are imaged in seismic reflection data and have been directly penetrated by boreholes, yet they remain poorly understood in terms of their style, detailed geometry, and distribution. Furthermore, the temporal, spatial and possibly genetic relationships between these post-salt igneous products and salt-tectonics are largely unknown. Documenting these possible salt-magma interactions is important to understanding the tectono-stratigraphic evolution of Campos Basin and other salt-bearing passive margin basins subject to magmatic activity. We use 2D and 3D seismic reflection and borehole data from the southeastern Campos Basin, offshore Brazil to map and characterize post-salt igneous sills and volcanoes, and to understand the interaction between salt tectonics and igneous products. We identified 99 sills emplaced within uppermost Aptian-to-Maastrichtian strata, 83 emplaced above the salt and 16 intra-salt, and 15 volcanoes within Upper Cretaceous-to-lower Paleogene strata, associated with a >310 km2 lava field. We also identify four, subsalt-sourced, vent-like structures, which vary in age from Paleogene to Late Cretaceous. Salt and overburden structures define a domain of extensional deformation on a base-salt basement high, and a domain of contractional deformation in the adjacent basement low. The relationship between igneous intrusions and salt tectonics is complex, i.e., in areas where they are common, sills appear to have locally restricted salt flow and the growth of large salt structures, whereas in other cases, salt structures and overlying faults appear to have partially acted as pathways to intruding magma, allowing it to ascend to relatively shallow depths. Extrusive igneous products exclusively developed after the main phase of salt movement. However, salt distribution influenced the location of volcanoes, given the latter developed where salt is welded or very thin. Salt flow and thickness also controlled the distribution of lava flow products, which accumulated in structural lows between large salt tectonic structures. Our work indicates a complex relationship between salt tectonics and magmatic emplacement that impact the post-rift evolution of Campos Basin. • We mapped 99 sills, 15 volcanoes and a >310 km2 lava field. • Sills emplacement locally influenced salt tectonics. • The intrusions do not affect the overall style of regional, thin-skinned deformation. • Salt-related faults acted as pathways to intruding magma. • Salt tectonics influenced the location of volcanoes, and lava distribution and thickness. [ABSTRACT FROM AUTHOR]

Despite the vast crocodyliform fossil record, little is known about the reproductive biology and nesting strategies of the extinct members of the group. Here we report a large accumulation of crocodilian fossil eggs from the type-locality of the baurusuchid Pissarrachampsa sera . Sedimentary facies and architectural elements of the site support a palaeoenvironmental model with a shallow lacustrine, playa-lake system interacting to ephemeral braided fluvial channels, with aeolian influence and development of sandy soils. The presence of pedogenic calcretes in the palaeosols indicates arid to semi-arid conditions. The crocodilian affinity of the eggs is supported by the thin eggshell which bears wedge-shaped shell units with tabular microstructures. Furthermore, taphonomic data support an autochthonous assemblage of eggs and skeletal remains, hinting at a monotypical stratigraphic horizon and suggesting P. sera as the egg-laying taxon. The repeated pattern of four (eventually five) eggs per clutch at the site demonstrates that P. sera laid fewer eggs compared to modern crocodilians, indicating that k-selected reproductive strategy pattern is pervasive in the fossil record of Notosuchia. In the crocodyliform phylogenetic framework, the k-strategy and the “egg clutch sizes” optimization of Notosuchia is opposite to the strategy with larger clutches consistently occurring in modern Crocodylia and Neosuchia, the sister clade to Notosuchia. Yet, the lack of data on more early-branching taxa renders unclear which pattern is plesiomorphic for Crocodyliformes as a whole. [ABSTRACT FROM AUTHOR]

The description of new titanosaur specimens unearthed from deposits of the Serra da Galga Formation (Bauru Group, Late Cretaceous) at the BR-262 site, near Peirópolis (Uberaba, Minas Gerais State, Brazil), sheds light on the taxonomy of two taxa previously known from the same area and geological unit: Baurutitan britoi and Trigonosaurus pricei . A comparative revision indicates that T. pricei represents a junior synonym of Ba. britoi , and that the BR-262 specimens belong to that latter species. The information provided by the new specimens also revealed that the paratype of T. pricei (MCT 1719-R), a caudal vertebral series, actually represents a new taxon, named here as Caieiria allocaudata gen. et sp. nov., Competing Interests: The authors declare that they have no competing interests., (© 2022 Silva Junior et al.)

Abstract: Two crocodyliform specimens recovered from the Upper Cretaceous of Argentina and originally referred to Peirosaurus torminni Price from Minas Gerais State, Brazil are reassigned to Gasparinisuchus peirosauroides gen. et sp. nov. No unique features are shared between the Brazilian and Argentinian specimens and many traits, including the presence of five premaxillary teeth, a noticeably smooth perinarial region, a lateral notch at the premaxilla–maxilla contact for the reception of an enlarged anterior dentary tooth, and the shape of the external nares, are widely distributed among peirosaurids and, in some cases, other mesoeucrocodylians. Though overlapping elements are limited to the premaxilla and the dentition, the broad, rounded rostrum, anteroposteriorly short premaxilla, reduced perinareal fossa, and short premaxillary interdental spaces in Gasparinisuchus differentiate it from P. torminni. Additionally, Gasparinisuchus is unique among peirosaurids for its broad rostrum and apparent absence of an antorbital fenestra. Reassignment of the Argentinian material formerly referred to Peirosaurus therefore removes one of the few specific links between the Cretaceous terrestrial biotas of Brazil and Argentina. [Copyright &y& Elsevier]

Abstract: An isolated caudal vertebral centrum of a theropod dinosaur was discovered in the Bauru Basin (Late Cretaceous) of Brazil, in the Maastrichtian São José do Rio Preto Formation. The vertebral centrum has pneumatic features that are similar to those in the megaraptoran theropods Aerosteon, Megaraptor, and Orkoraptor. For example, all these taxa share with the caudal centrum here described the presence of true pleurocoels or pneumatic foramina, immersed within a depression or fossa. Thus, the specimen is considered the first record of Megaraptora in Brazil. The present analysis provides new information on the vertebral caudal anatomy of this clade of bizarre Cretaceous theropods. [Copyright &y& Elsevier]

The records of Cretaceous Brazilian titanosaurs assigned to the Patagonian genus Aeolosaurus Powell (Dinosauria, Sauropoda, Titanosauria) are discussed. The fragmentary and isolated nature of many of the specimens and the incomplete knowledge of the diversity and phylogenetic relationships of Brazilian titanosaurs generate uncertainty regarding the taxonomic assignments. Revision of the Brazilian specimens attributed to Aeolosaurus suggests that there are no characters indicating the presence of this Patagonian genus in the Late Cretaceous of Brazil. The conclusion that the relationships of these specimens were incorrectly recognized, points out that better taxonomic procedures, using consistent data, such as the presence of well-defi ned apomorphies, are needed for correct taxonomic designations, paleogeographic and paleobiostratigraphic inferences and the proposal of biochrons. [ABSTRACT FROM AUTHOR]

PHYSA MEZZALIRAI: A NEW GASTROPOD FROM ADAMANTINA FORMATION (BAURU BASIN), LATE CRETACEOUS, SÃO PAULO, BRAZIL. Physa mezzalirai n. sp. (Family Physidae, Order Basommatophora), a fresh-water gastropod is described from sand-silty beds of Adamantina Formation (Bauru Basin), Late Cretaceous of São Paulo State, Brazil. This is the first occurrence of gastropods in the analyzed region and to this geological unit where the paleontological content is mostly known by the big turtle bones and shells, and by other vertebrate remains. These finding attests the paleontological potential of Adamantina Formation to the study of invertebrate fossils, nearly neglected in the moment, and could help in the refinement of fluviolacustrine paleoenvironmental and about the paleoecology during the time of Bauru Group depositon. [ABSTRACT FROM AUTHOR]

Abstract: The Marília Formation, which crops out in southeastern Brazil, is interpreted as a Late Cretaceous eolian sand sheet area. The sedimentary succession, ca 110m thick, is characterized by alternating strata of eolian deposits and paleosols. The paleosols constitute more than 66% of the thickness, and are an important element in the interpretation of the paleoenvironmental controlling factors which affected the soil formation in this eolian sand sheet. In this paper six paleosol profiles are described and assigned to two pedotypes: Itaja and Apore. The Itaja pedotype is constituted of a sequence of five superimposed polygenetic profiles which show different phases of clay illuviation and carbonate precipitation, and it has been classified as Aridisol. The Apore pedotype overlies the Itaja pedotype. This pedotype shows an increase in leaching, CIA-K ratios, reddening, and illuvial clay features in respect to Itaja, and has been classified as Alfisol. The analysis of the factors which controlled the soil formation revealed that both pedotypes formed on a stable landscape probably covered by a community of low stature plants, in which the soils had sufficient time to develop very mature profiles. The changes in soil-forming processes were driven principally by variations in available soil moisture from precipitation. Using depth-to-carbonate functions from Bk and CIA-K proxy from Bt horizons of the Itaja pedotype, mean annual precipitation (MAP) estimates range from 240 to 1078mm/yr, respectively. These contrasting climatic conditions resulted in the superimposition of arid or semi-arid with more humid climates and determined the considerable change in the pedogenic features, with many horizons showing the interlacing of calcite and clay features. In the Apore pedotype CIA-K proxy from Bt horizons estimates that averaged MAP was around 900mm/yr, and the prevalent humid conditions can be attested by soil properties and abundance and depth of root traces. Our results show that the diversity in pedotypes is mainly attributed to differences in paleoclimatic conditions during Maastrichtian time, and that eolian sedimentation was restricted to periods of harsh arid conditions, as in semi-arid climates, with MAP estimates around 240mm/yr, the formation of soils with well developed calcic horizons was possible. [Copyright &y& Elsevier]

Abstract: Few previous studies have given significant consideration to the palaeosols in aeolian sand sheet sedimentary successions and, mainly, to their palaeoenvironmental and stratigraphic meaning in interaction with the deposits. These themes are considered in this study that deals with the depositional architecture and the factors controlling the construction, accumulation and preservation of an ancient aeolian sand sheet, that forms part of the Adamantina and Marília formations, in the Bauru Basin (Late Cretaceous, Brazil). In the NW portion of the Bauru Basin, these two units, ca 220m thick, consist of sandstone, and secondarily of sandy conglomerate and mudstone, and are characterised by vertically alternated palaeosols and deposits. Facies analyses of the deposits and macroscopic characterisation of the palaeosols in 45 outcrops were integrated with laboratory analyses that consisted in descriptions of slabs of rock samples, petrographic analyses, clay mineralogy determination, geochemical analyses of the major oxides, and micromorphological characterisation of the palaeosols. Three architectural elements were recognised: palaeosols, wind-ripple-dominated aeolian sand sheet deposits, and ephemeral river deposits. The palaeosols constitute 66% of the entire sedimentary succession, and consist principally of Aridisols and, subordinately, of Alfisols, Vertisols, and Entisols. The wind-ripple-dominated aeolian sand sheet deposits (25%) are composed of sandstone, organised in translatent climbing wind-ripple strata, and secondarily of sandstone and mudstone deposited by infrequent floods. The ephemeral river deposits (9%) consist of sandy conglomerates 4m thick and ca 2km wide. Wind-ripple-dominated aeolian sand sheet deposits formed during relatively dry climate period on an unstable topographic surface of an aeolian sand sheet, where aeolian deposition or erosion prevailed. Palaeosols and ephemeral river deposits formed in a more humid climate period on a stable topographic surface of the aeolian sand sheet. Six bounding surfaces permitted the subdivision of the study formations into genetic geological bodies, revealing different spatial and temporal orders. Two first order surfaces separate mature palaeosol profiles (Aridisols, Alfisols, and Vertisols) from overlying aeolian deposits or other mature palaeosol profiles. A second order surface separates immature palaeosols (Entisols) from overlying aeolian deposits. A third order surface constitutes the channel bottom. A fourth order surface is located at the bottom of flood deposits. A fifth order surface divides translatent wind-ripple. The constructional phase of the aeolian sand sheet occurred during the relatively dry climate period, when the available sediment was supplied from the material originally deposited by rivers and stored during a more humid period (primary supply), and by soil erosion during a drier climate (secondary supply). The accumulation surface was controlled during the drier climate by cemented Bk horizons over Aridisols and by the force of the wind blowing over the other soils or deposits. Otherwise, during the more humid climate, the accumulation surface was a stabilised surface represented by the soil. Preservation was dominated by tectonically induced subsidence and burial. [Copyright &y& Elsevier]

Abstract: The Turonian–Maastrichtian beds of the Bauru Group, western São Paulo State (Brazil), have yielded a diverse biota. The nine species of mesoecrocodilians are all mesosuchians. There is a single frog, a Neubatrachia. The vertebrates include, four types of fishes, a neobatrachian frog, an anilioid snake, two lizard, six species of podocnemid turtles, nine species of mesosuchian mesoecrocodilians three theropods, two birds, five titanosaurid sauropods, and one mammalian. The invertebrates include one cyclo, one cyclophoroid and eight pulmonates. Plants are represented by only two carophyte species. The biota from western São Paulo State is one the most diverse of the Late Cretaceous in Brazil. The biota from this area confirms that Bauru Group was connected to Patagonia and other Gondwanan areas during the Late Cretaceous. [Copyright &y& Elsevier]

The Peirópolis paleontological site (Late Cretaceous, Maastrichtian) in Minas Gerais State, Brazil yielded an important assemblage of fossil vertebrates. The typical occurrence of South American widespread taxa in Peirópolis is important for correlation between the Brazilian Bauru Basin and Argentinean Late Cretaceous basins. The fishes, turtles, anuran, crocodilians and dinosaurs known from Peirópolis (Marília Formation) resemble the Patagonian latest Late Cretaceous vertebrate faunas but lacks ornithischian dinosaurs. [ABSTRACT FROM AUTHOR]

Abstract: The Sphagesauridae is a family of Crocodyliformes exclusively known for the Brazilian Late Cretaceous Bauru Basin. This lineage reveals how diverse was the morphology and ecology of terrestrial Crocodyliformes during the Late Cretaceous of Gondwana. Here is described Armadillosuchus arrudai gen. et sp. nov., a sphagesaurid that presents some mammal-like morphological features, such as propalinal and alternate unilateral jaw occlusion pattern and heavy body armor, composed of a rigid shield and mobile-banded section as in extant armadillos (Xenarthra, Dasypodidae). These unusual morphological features contrast to the double row of osteoderms observed on the closest relatives of A. arrudai. As its mammal analogs, A. arrudai presents some evidence of fossoriality and an exclusive terrestrial life style in contrast to the extant alligatorids and crocodylids. [Copyright &y& Elsevier]

A new Late Cretaceous titanosaur sauropod from the Bauru Basin of Brazil, Uberabatitan ribeiroi gen. et sp. nov., represented by at least three specimens, is described. The material comes from a level of coarse sandstone within the Serra da Galga sequence in Uberaba County, Minas Gerais State. The fossiliferous strata belong to the Marília Formation (Serra da Galga Member), Bauru Group, considered to be Maastrichtian in age. The fossils occur in the uppermost levels of the above-mentioned unit; thus, Uberabatitan ribeiroi is the youngest titanosaur to have been recorded from the Bauru Basin. The autapomorphies that support the new species are: (1) anterior and mid-cervicals with postzygodiapophyseal lamina (podl) segmented in zygapophyseal and diapophyseal laminae, of which the first extends rostrodorsally over the second; (2) mid-dorsals with a robust lateral lamina formed mainly by a diapophyseal lamina (probably homologous to the postzygodiapophyseal lamina), and, to a lesser extent, by a relic of the spinodiapophyseal lamina (spdl); (3) mid (and probably posterior) dorsals with accessory neural laminae, which are lateral to the prespinal lamina, and probably homologous to the spinoprezygapophyseal laminae (sprl); (4) mid-caudal centra with deeply excavated lateral faces; (5) pubis very thick and robust, with a very stout longitudinal crest on its external (ventral) face; and (6) proximal end of the tibia with a prominent lateral protuberance, which articulates with an equally prominent medial knob of the fibula. The titanosaurian assemblage at Uberaba includes, apart from U. ribeiroi, well-preserved specimens assigned to species of uncertain affinities ( Trigonosaurus pricei and Baurutitan britoi), as well as a few vertebrae assigned to aeolosaurines. [ABSTRACT FROM AUTHOR]

Aim To analyse the worldwide distribution patterns of Turonian marine biotas using a panbiogeographical approach. Location Turonian localities of southern and north-eastern Brazil, Mexico, Canada, central Europe, England and Morocco. Method Panbiogeographical track analysis. Results Nine generalized tracks and six nodes were found. The generalized tracks comprise two vicariant track patterns (one northern and one mid-southern) across the Atlantic. Main conclusions The generalized tracks show clearly two separate marine biotas, which were associated with the proto-South Atlantic and the proto-North Atlantic oceans. These generalized tracks, as well as the two vicariant track clusters between the north and south Atlantic, are identified by vicariant relationships shared by most of the taxa analysed, and illustrate the final break up of the Gondwana and Laurasia supercontinents and the consequences of vicariant events for the biogeography of the Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Abstract: This article offers a detailed overview of mesoeucrocodylian assemblages recovered from the Late Cretaceous southern South America Bauru and Neuquén groups as a result of extensive research during the past 110 years. The Bauru (Brazil) and Neuquén (Argentina) groups yield numerous mesoeucrocodylian remains, mainly of Turonian–late Maastrichtian (Late Cretaceous) age. The majority of the discoveries were made in the Adamantina and Marília formations of Minas Gerais and São Paulo states, Brazil, and Candeleros and Bajo de la Carpa formations of Neuquén and Río Negro provinces, Argentina. Sixty formally described species of mesoeucrocodylians are recognized on the basis of disarticulated materials; among them, notosuchians, sebecosuchians, and peirosaurids are the best represented. At least one species is common to the Bauru and Neuquén groups, and close phylogenetic affinities are postulated for the remaining taxa. The fossil record of these two South American units shows three main peaks of diversity: in the Cenomanian of Argentina, the Santonian of Argentina and Brazil, and the Maastrichtian of Brazil. The absence of notosuchians and sebecosuchians in the late Campanian–Maastrichtian of Patagonia is coincident with the paleoenvironmental changes in that landmass by that time, as well as with the increase in diversity of several groups of theropod dinosaurs. In contrast, highly specialized carnivorous mesoeucrocodylians are abundant in the Maastrichtian of the Bauru group of Brazil, whereas other tetrapod carnivorous groups are scarcely represented. [Copyright &y& Elsevier]

Abstract: In this contribution is given a preliminary up-to-date annotated list of all fossil vertebrates from the Turonian–Santonian Adamantina Formation, Bauru Group where it occurs in the Prata paleontological district which is located 45 km to the west of Prata in Minas Gerais State, Brazil. The Adamantina Formation is a reddish sandstone in the Triângulo Mineiro region. These fluviolacustrine sediments were deposited in a semiarid environment. Three fossil vertebrate sites occur in the Prata paleontological district. The diversity of vertebrates in the Adamantina Formation is modest, and its components comprise a mixture of typical austral Gondwana taxa (such as abelisaurids, Aeolosaurus) and boreal Gondwana taxa (such as Carcharodontosauridae). The absence of Laurasian taxa in the upper part of the Bauru Group is noteworthy. Excepting some turtles, crocodylians, and one titanosaurid, most of the specimens discovered in this Group are based on fragmentary and isolated remains, which make it difficult to correctly identify the fossils. For this reason, many of the taxa have only been identified in a preliminary manner. Despite this drawback, the dinosaurs are typical Gondwana forms with no evidence of Laurasian affinities. This is concordant with the idea that the Laurasian dinosaurs entered South America at the end of the Late Cretaceous; i.e. after the Turonian–Santonian, the age of the Adamantina Formation. [Copyright &y& Elsevier]

Because of their relatively reduced tectonic influence, post-rift sedimentary successions have a propensity to preserve climatically-driven cyclicity over long durations. Here we present an integrated cyclostratigraphic and sequence stratigraphic study of the post-rift Limoeiro sedimentary Formation (Fm) of the Foz do Amazonas Basin (offshore Brazil), which spans the entire Late Cretaceous epoch (almost 35 Myr long). The principal goal of the present study is to decipher very long (multi-Myr) sedimentary cyclicities and their potential origin(s) in order to delineate the main controlling factors of post-rift sediment sequences and packages. We used gamma-ray (GR) well-log data for cyclostratigarphy, and seismic data for sequence stratigraphy. Time-series analysis of GR data shows a rich series of Milankovitch frequency bands. In particular, long-period cyclicities (405 kyr, 2.4 Myr, 4.7 Myr and 9.5 Myr) are detected with high fidelity. Seismic and sequence stratigraphic interpretation shows a striking sea-level (SL) depositional sequence order, matching the 4.7 Myr orbital cyclicity inferred from cyclostratigraphy. Longer SL sequences interpreted in previous studies from the Limoeiro Fm closely match the 9.5 Myr GR related orbital cycles. Thus, we infer that the post-rift Limoeiro Fm was deposited continuously under astronomical forcing over the Late Cretaceous epoch, resulting in an extraordinary record of direct base- and sea-level responses to Milankovitch climatic forcing, including longer (multi-Myr) periodicities. The 4.7 Myr orbital component is recorded for the first time in SL sedimentary proxies, thus allowing here to update SL hierarchical orders. We suggest that third-order, and second-order and suborders SL sequences were most likely paced by long-period astronomical cycles (2.4 Myr eccentricity, and 4.7 and 9.5 Myr orbital cycles, respectively. • An integrated cyclo-seismic stratigraphy detects 2.4, 4.7 and 9.5 Myr orbital cycles. • 2.4, 4.7 and 9.5 Myr orbital cycles match third and second-order sea-level sequences. • The 4.7 Myr orbital cycle is highlighted for the first time in sea-level record. [ABSTRACT FROM AUTHOR]