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Integration of late Quaternary continental and marine proxies allows improved reconstruction of palaeoenvironment and palaeoclimates models for the south-eastern coast of Brazil. In this paper, we analyse pollen, fern spores, and dinoflagellate cysts in a marine sediment core (GL74) over the last ∼109 kyr. Results showed that, between 109 and 89.5 kyr, low sea levels promoted the expansion of herbaceous taxa across open areas while climatic conditions were relatively warm and humid, as indicated by the high frequency of Atlantic rainforest Ombrophilous forest pollen types and abundant of fern spores. Between ∼79–49 kyr, higher concentrations of palynomorphs were recorded, which were likely related to the low relative sea level during the last glacial period. During this interval, there was a decrease in tree pollen grains and an increase in shrub and herbaceous pollen grains, indicating cold and relatively dry weather conditions. In the Holocene period, the low deposition of palynomorphs may have been influenced by the gradual submergence of the central part of the Brazilian coast. This process was associated with warm and humid climatic conditions, as suggested by the expansion of rainforests and the presence of hygrophyte/aquatic taxa and fern spores, as well as the retraction of grassland pollen types. Dinocyst assemblages suggest that nutrient-rich waters and/or the presence of upwelling cells were dominant between ∼109–88 kyr, but gradually reduced between 88 and 65 kyr (and/or ∼ 88–20 kyr) under the influence of subtropical fronts. The study culminated in the dominance of unproductive warm water in the upper column between 65 and 0.5 kyr. • Correlation of continental and marine proxies in south-eastern Brazil during the late Quaternary Late • Quaternary dynamics of the South Atlantic Ocean based on dinocysts • Reconstruction of palaeovegetation and palaeoclimate for the last ∼109 kyr along the southeast coast of Brazil [ABSTRACT FROM AUTHOR]

A rich insect fauna is found in the Cretaceous (Aptian) Nova Olinda Member of the Crato Formation in the Araripe Basin, northeastern Brazil. The Crato Formation was deposited close to the centre of the supercontinent Gondwana, prior to significant rifting. In this paper, we analyzed remains of 1135 insect specimens, representing 55 families, within two limestone facies of the Nova Olinda Member: pale yellow and dark gray limestones. We collected taphonomical data and assessed the paleoecological significance of insect faunas in terms of their distribution and interaction with the paleoenvironment. The insect fauna is dominanted by fully terrestrial taxa despite preservation in an aquatic paleoenvironment. Considering both facies, the distribution of insect families is similar throughout the Nova Olinda Member, which excludes possible overlapping of one entomofauna over another. The pale yellow limestones near the top of the section are richer in fossil insect content and show a higher incidence of aquatic and semiaquatic insects preserved in dorsoventral view compared to the dark gray limestones. This suggests that the Crato insects preserved in the pale yellow limestones experienced short transport distances or prolonged decay or both. In contrast, insects preserved in the dark gray limestones appear proportionally with higher degrees of disarticulation than those preserved in the pale yellow limestones, indicating that these insects underwent a higher degree of postmortem transport in the biostratinomic stage. Compared to descriptions of other Early Cretaceous assemblages, the taxonomic literature of Crato Paleoentomofauna shows distinct differences. The Yixian and Zaza formations are described as being dominated by beetles and wasps. The Crato Formation, however, is relatively richer in Paleoptera species. Both the sedimentary facies studied and the paleoentomological content reveal a complex ecosystem inserted in a depositional setting, similar to modern long-standing wetlands, and where periodically flooded zones were surrounded by dry lands with xeromorphic vegetation. • Crato insects preserved in the dark gray limestones appear proportionally with higher degrees of disarticulation. • The paleoentomological content reveals an ecosystem inserted in a setting similar to modern long-standing wetlands. • Compared to other Early Cretaceous assemblages, the Crato Paleoentomofauna is relatively richer in Paleoptera species. [ABSTRACT FROM AUTHOR]

Paleosols are an under-utilized tool for paleoenvironmental and paleoclimatic reconstruction in Brazilian intracontinental basins. The Itapecuru Formation, from the Lower Cretaceous of the Parnaíba Basin, consists of a 600-m-thick succession of interbedded very fine-to-fine-grained sandstone, mudstone, and paleosols containing rich fossil assemblages. This paper provides a detailed description of the macro and microscopic pedogenic features of a hydromorphic paleosol profile whithin the Itapecuru Formation. Analyses of clay mineralogy and whole-rock geochemistry in the hydromorphic paleosols at the Prata locality are used to infer pedogenic processes, paleoclimate, paleohumidity and paleovegetation. Estimates of paleoprecipitation and paleotemperature using climofunctions, chemical index of alteration without potassium, and paleosol weathering index proxies (PWIs) show values ranging from 810 to 1042 mm/yr (SE = ±78.1 mm/yr) and 10.9 to 11.8 °C (SE = ±0.23 °C), respectively. Climofunction values (MAP and MAT), paleohumidity, Kӧppen aridity index, and pedogenic clay mineral content suggest a humid paleoclimate during soil-forming and weathering processes. Based on these climate data and previously published paleogeographic and palynological studies, the Cretaceous (Albian) Prata pedotype was formed within the equatorial humid belt with vegetation of wet tropical forests. • Alluvial paleosols are characterized in the Parnaíba Basin. • Based on mineralogy and geochemistry analysis, six pedogenic processes were recognized along the Prata pedotype. • Climofunctions values suggest a humid paleoclimate during paleopedogenic modification. • The Albian paleolatitude of Brazil, along with studied climate data, suggests the influence of the Equatorial Humid Belt. • The soil taxonomy following paleoclimate data and pedogenic processes define the Prata pedotype as Ultisol Aquults. [ABSTRACT FROM AUTHOR]

This paper examines a glacial diamictite-bearing succession from the upper Itararé Group (Taciba Formation) in eastern Paraná Basin, Brazil. The object of study provides the opportunity to investigate in detail the late stages of glacial sedimentation during the Late Paleozoic Ice Age (LPIA) in this sector of SW Gondwana, with implications for glacial cyclicity and regional paleo-ice flow reconstructions. Sedimentology, geological mapping and palynological analysis allowed the recognition of four facies associations, comprising subaqueous outwash, mass-transport, tide-influenced delta-front, and tide-influenced delta plain deposits. The succession records at least two episodes of ice-margin advance and retreat into a marine-influenced environment and can be placed in the earliest Permian based on the palynomorph assemblage. Cross stratification in outwash facies and deltaic deposits indicate sediment transport to the SW, the same revealed by deformational structures in mass-transport diamictites derived from downslope resedimentation of glaciomarine sediments during deglaciation. A glacial source to NE is therefore indicated and is in agreement with paleo-ice flow directions obtained from previously studied localities to the north. This north-derived early Permian glaciation contrasts with glacial sources to the SE recognized in the lower and middle intervals of the Itararé Group. The scenario suggests a geometric reconfiguration of the Paraná Basin during the LPIA and the migration of ice centers with time during the Late Paleozoic Ice Age in SW Gondwana. [ABSTRACT FROM AUTHOR]

In this paper, we use palynology and geochemical proxies to reconstruct late Quaternary vegetation changes within the hydrographic basin of Parnaíba, Northeast Brazil, over the last 130 kyrs. Findings are based on the analysis of a marine sediment core (GL-1248) retrieved from the western equatorial Atlantic (0°55.2′S, 43°24.1′W), close to the coast. Geochemical proxies (Fe/K ratio and Ɛ Nd) indicative of soil erosion match changes in reconstructed vegetation, suggesting a dynamic pattern of hydrological disturbances and ecosystem evolution. Given that reconstructed vegetation does not present the same response to precipitation anomalies on the millennial scale, we sought the main drivers of vegetation changes in the Parnaíba watershed. Results indicate that vegetation succession was primarily influenced by austral insolation from March to May, which triggered changes in the pioneer vegetation types. Our study improves the knowledge of tropical vegetation dynamics in an orbital framework, suggesting 23-kyr precessional cycles as the main driver of landscape evolution in Northeast (NE) Brazil. We also infer that such past climate change events may have been a key causal factor of the high biodiversity of the Neotropics, mediated through the biological exchange of the Amazon and Atlantic rainforest species via ecological forest corridors in the semi-arid Northeast Brazil. • We discuss vegetation change and how it reflects hydrological changes within the Parnaíba Basin, northeastern (NE) Brazil, over the past 130 kyrs • Geochemical proxies (Fe/K ratio and ƐNd) in core GL-1248 are synchronous with reconstructed vegetation patterns, highlighting periods of enhanced or reduced local soil erosion during hydrological disturbances • We define three major vegetation groups (tropical dry forest, lowland rainforest, and wetland), and the discrepancy in water requirements between tropical dry forests and lowland rainforests is discussed • Analysis of the hydroclimatic mechanisms in NE Brazil that triggered the succession of vegetation during glacial phases is discussed [ABSTRACT FROM AUTHOR]

Studies dealing with the reconstruction of Holocene climate change of tropical areas are scarce. Of these, multi-proxy investigations using peatlands are still absent. In this paper, we present the Holocene record of environmental changes in central–eastern Brazil reconstructed from a core sampled in Pau de Fruta mire (Serra do Espinhaço Meridional, Brazil). We combined palynological and geochemical analyses, supported by core stratigraphy, 14 C dating and multivariate statistics. The location of the mire is ideal because it is in an area which is directly associated with the South Atlantic Convergence Zone (SACZ). Six main phases of change suggested by vegetation and local and regional landscape dynamics were described. In phase I (~ 10,000–7360 cal. yr BP) the climate was very wet and cold and was accompanied by soil instability in the mire catchment (severe local erosion) and the 8.2 ka event was easily recognizable by a large increase in the deposition of regional dust. Phase II (~ 7360–4200 cal. yr BP) was characterized by wet and warm conditions, catchment soil stability and enhanced deposition of regional dust. In phase III (~ 4200–2200 cal. yr BP), climate was dry and warm and soil erosion in the catchment increased again. In phase IV (~ 2200–1160 cal. yr BP) dry and punctuated cooling was reconstructed, together with enhanced deposition of regional dust. Phase V (~ 1160–400 cal. yr BP) reflects sub-humid climatic conditions (like the current climate), the lowest inputs of local and regional dust and the largest accumulation of peat in the mire. While in phase VI (< ~ 400 cal. yr BP) sub-humid conditions continued but both local and regional erosion significantly increased. Our results demonstrate that the tropical peatlands of Serra do Espinhaço Meridional contain relevant records of Holocene climate changes, and that a multi-proxy approach offers good opportunities for a detailed reconstruction of palaeoenvironments. [ABSTRACT FROM AUTHOR]

Burrowing behavior is an important adaptation of animals that live in arid and semi-arid conditions. In this paper, we describe examples of vertebrate burrows from the Upper Cretaceous (Maastrichtian) Adamantina Formation of the Bauru Basin, Brazil, most likely produced by turtles. The Adamantina Formation preserves abundant and diverse turtle body fossils such as Bauruemys elegans (Testudines: Pleurodira); however turtle burrows have not been previously documented. The newly reported burrows are preserved in fluvial sandstone facies and exposed in sections that partially preserve their three-dimensional geometry. Burrows are simple J-shaped tunnels with a cross-sectional shape that is semicircular (half-dome) with a flattened floor. Such burrows show a partially preserved entrance with an inclined ramp angle (22°), and grooves and ridges up to 1 cm in width preserved along the burrows walls and floor. The architecture and sedimentary facies of the host sandstone body, together with the occurrence of Taenidium barretti and the absence of rhizoliths, suggest that the burrow was excavated by scratch digging into an exposed point bar of a meandering river channel. Based on burrow morphology, dimensions, as well as ridges,and grooves in the walls and floor, we propose that burrows were formed by a chelonian (such as a freshwater turtle) during aestivation. We highlight that these are first examples of turtle burrows reported from the Cretaceous, and their occurrence reinforces the hypothesis that the original function of turtle shells was as an adaptation to fossorial behavior. [Display omitted] • The first freshwater turtle burrows from Cretaceous of South America. • The burrows occur in fluvial point bars of Adamantina Formation. • Evidence of fossorial and aestivation behavior in turtles during Cretaceous. • Results reinforce the hypothesis of fossorial behavior in stem turtles. [ABSTRACT FROM AUTHOR]

Abstract: The occurrence of crowded Rosselia ichnofabric in Early Devonian deposits of ‘Transition Beds’ (Western Gondwana Paraná Basin, southern Brazil) and the paleobiology and paleoecology of its potential tracemakers are discussed in this paper. Crowded Rosselia ichnofabric has been recorded chiefly in Cenozoic storm beds associated with high sedimentation rates on the inner shelf, and is usually interpreted as resulting from opportunistic behavior of terebellid polychaetes. Rosselia is a common ichnotaxon in the archetypical Cruziana ichnofacies, developed preferentially in fair-weather deposits formed in inner shelf settings. During storm surges, however, this endobenthic community is strongly affected, decimating those that are unable to escape. New records presented herein reinforce the conclusion that short-term colonization represented by crowded Rosselia ichnofabric occurs essentially in erosive storm deposits of high sedimentation rates. Rather than being opportunistic, the crowded Rosselia ichnofabric appears to be the result of a strategic behavior developed by stress-tolerant terebellid polychaetes in inner shelf zones during or just after storm surges. This strategic behavior appeared during the early Paleozoic and was adopted by terebellids from their earliest appearance. [Copyright &y& Elsevier]

Abstract: The Bananal Basin is the most important intracratonic Quaternary sedimentary basin of South America and preserves a good record of the paleohydrological conditions of Central Brazil at the Cerrado–Amazon ecotone. This area is currently a large tropical plain, seasonally flooded by rainfall and water table saturation that can be classified as a seasonal wetland. This paper presents a geological and geomorphological analysis supported with geochronological dating aiming to reconstruct the Pleistocene environmental history of the Bananal Basin. The basin was filled by the sediments sourced by the Araguaia–Mortes fluvial system. The deposits belong to the Araguaia Formation which covers ~106,000km2 of the Bananal Basin. TL and OSL chronologies of the Araguaia Formation show that sedimentation started at least in the Middle Pleistocene (MIS 7) but aggradation and avulsion processes were important in the Lower–Middle Pleniglacial between 70.5ka and 34.0±4.6ka (MIS 4 and 3) and in the Upper Pleniglacial between 24.5±3.1 and 17.2±2.3ka (MIS 2). River avulsions were more intense in the lower Bananal Basin (Bananal Island region). Remarkably, we did not record ages between 17ka and 10ka. Although avulsion seems to have been more active in the past, the abandonment by the Araguaia of a channel belt, now occupied by the underfit Javaés River, indicates that avulsion is still active. The avulsion processes are mainly related to palaeohydrological changes, although present-day seismic activity is also recorded. Additional data is needed to generate a more detailed scenario for the older Middle Pleistocene deposits. The data is remarkable, however, because it is the first Middle Pleistocene record described in a large alluvial tropical system in Brazil. The fluvial record is temporally in agreement with records from other large Brazilian fluvial systems such as the Amazon and Paraná basins. The Bananal plain, however, is unique because of its particular style of sedimentation and geomorphologic processes that generated a mega-scale anabranching-like complex pattern of paleochannels presently occupied by underfit streams. [Copyright &y& Elsevier]

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]

In the southern tropical Andes, previous studies performed on lacustrine basins display large water-level fluctuations due to changes in the precipitation minus evaporation balance during the Holocene. Significant changes in groundwater levels were also inferred from river paleowetland deposits in northern Chile and the northern Bolivian Altiplano but the discrepancies which appeared in the data from paleolakes and paleowetlands are still not understood. In this paper we present stratigraphy and diatom analyses in new paleowetland records from non-glacial valleys. These data, compared with previous results, show that non-stormy precipitation (recorded by fine and/or organic sedimentation) dominated continuously from ∼11 200 to ∼1500 cal yr BP and that convective rainfall (recorded by strong erosion) occurred only episodically in the northern Altiplano. Convective rainfall was similar to the type of precipitation which nowadays occurs during the rainy season (austral summer) when the tropical easterlies from the Atlantic reach the Bolivian Andes. Non-stormy precipitation is interpreted as a result of an intensification of cold-air incursions from southern polar regions, in good agreement with data from Brazil. The maximum intensity in cold-air incursions occurred during the Early Holocene and coincided with a climatic optimum in Antarctica and a considerably reduced El Nin˜o Southern Oscillation (ENSO). During the Middle and Late Holocene, cold-air incursions decreased and the ENSO frequency increased. We suggest that the interactions between the southern high and low latitudes, by means of cold-air incursions and associated changes in the west wind flow, have been the main mechanisms involved in climatic changes at the latitudes of Bolivia. [Copyright &y& Elsevier]

Drowning unconformities are surfaces characterized on seismic data by high amplitude contrast between deepwater and shallow water facies. Such surfaces are created by the covering of the platform by onlapping siliciclastic sediments or other non-platform material. The key aspect of this paper is the application of the drowning unconformity concept, commonly used in marine settings, to a more restrictive one: the coquinas of the Itapema Formation, in the pre-salt succession of the Santos Basin (Brazil). In the studied area the sequence boundaries of the deposits related to the Itapema Formation are often associated with high reflectivity seismic horizons, which are tied to radioactive peaks of low-energy sedimentary facies in the gamma ray logs and also to the siliciclastic supply rate increase. However, the stratigraphic significance of these reflectors still lacks further investigation and an adequate description. In this way, it is proposed that the space-time filling of the Itapema Formation occurred by the successive migration of proximal facies towards the structural highs, under continuous accommodation space generation conditions and high carbonate production rate, with the depocenters limited by rapid expansions of the basin. The results presented here, therefore, suggest that the sedimentary record of this section was punctuated by instantaneous transgressive surfaces that altered the ecological accommodation, forcing the backstepping of the coquina deposits and the development of a drowning unconformity in the final stage of the Itapema Formation deposition. This configuration produced at the top of this unit a specific facies association characterized by packstones and mudstones composed of micritized grains, which increase in volume and thickness towards the structural lows and tend to be thinner on the way up to the structural highs, where they may be eroded by the Pre-Alagoas Unconformity. The correct identification of such surfaces is essential for understanding the sedimentary filling of the studied area. Depending on which surface is mapped, they may be related to different processes and occur in opposite positions in the base-level cycles. Thus, we propose the existence of two surfaces at the end of the deposition of the Itapema Formation. The first limits the top of the coquinas and is represented by the contrast of low-energy sediments (packstones and micritized mudstones) and the coquinas deposits, configuring the platform drowning itself. The second one, in turn, is understood here as the Pre-Alagoas Unconformity, a subaerial unconformity associated with the regional platform exposure, developed after the drowning events recognized here. • Seismic and well characterization of drowning unconformities in the pre-salt succession. • Drowning unconformities in a non-marine environment setting. • Shut-down of the coquina factory associated with a rapid drowning in early Cretaceous. [ABSTRACT FROM AUTHOR]

Experimental taphonomy using microbial mats offers new insights into the mechanisms involved in the decay of organisms and their preservation as fossils. In this paper, the experimental decay products of soft-bodied insect larvae (the greater wax moth, Galleria mellonella , and the mealworm, Tenebrio molitor) in microbial mats have been described and compared with those of grylloid fossils derived from the Cretaceous Crato Formation of Brazil. This novel approach characterises the decay and mineralisation of different tissues (cuticle, gut tract, silk gland, trachea, and fat body tissues) using transverse histological sections. Multivariate seriation statistics using histology indicate a significant non-random process, in which the two species show the same general decay sequence, namely: decay of fat bodies and muscles on Day 11, digestive degradation and occurrence of endogenous bacteria on approximately Day 30, and degradation of cuticles and tracheal networks (the most perdurable) on Days 60 and 120, respectively. Principal component analysis, based on the qualitative features of the decaying state of tissues, showed that the greatest alterations occurred between Days 60 and 180 in the controls without mats; however, in the microbial mat experiments, larvae showed better preservation overall. Based on scanning electron microscopy and energy-dispersive X-ray spectroscopy, mineralisation of the larvae extends outside the cuticle and inner tissues. The predominance of certain anions (sulfate, chloride, and phosphate) is associated with the microbial activity of the mat community and the composition of water. The organic mesh of exopolymeric substances and cyanobacteria enriched in elements (e.g., Na and Mg) formed an amorphous crust that covered the larval body. This crust is similar to the massive crystallised external film found on the grylloid fossils derived from the Crato Formation of Brazil. The minerals were found to vary with location and time, with sulfates appearing mostly internally and for longer periods. Sulfurisation is discussed as the principal preservation process and is rapid in the early stages of organic matter decay. This comparison between the outcomes produced by taphonomic experiments using actual microbial mats and exceptionally preserved fossils can provide valuable information to understand more about the formation of numerous Konservat-Lagerstätten. • Soft-tissue decay and mineralisation was tracked using histological sections in insect larvae; • Histological decay resulted in a significant non-random process; • The distribution of minerals has a time and location-dependent pattern; • Exceptional preservation in Crato Formation can be explained by the organic crust generated by the microbial mat [ABSTRACT FROM AUTHOR]

Shell concentrations are one of the most distinctive features of the Holocene coastal stratigraphy in the southern portion of Santa Catarina State, southern Brazil. In this paper, we integrated stratigraphic, geochronological, geophysical, and taphonomic data to discuss the processes involved in the genesis of shell concentrations in a siliciclastic and subtropical setting, a useful analogy for ancient shell concentrations in semi-closed environments affected by storms. The data indicated the succession of three facies associations (FA): bay, lagoon, and back-barrier. This succession implies a grain size fining-upward trend that is representative of a gradual shallowing. Interpretation of GPR sections revealed that the passage from the bay to lagoonal deposits occurred by forming a laterally continuous, high-amplitude surface overlain by sigmoidal reflections, which characterized the progressive basinward backstepping of the lagoonal margin. Shell concentrations in bay deposits are an allochthonous product of storm flows in shallow waters. In contrast, accumulations of the bivalve Anomalocardia brasiliana had their valves reworked in the lagoonal margins and transported to the bottom, characterizing a parautochthonous accumulation. In this study, the correlation of taphonomy and grain size indicates that in bay FA, the loss of periostracum is correlated with increased gradients of fine sand, and part of the shell samples correlates to corrosion and abrasion in increased gradients of medium sand and decreased ones of fine sand. Additionally, in the lagoon FA, the loss of periostracum depends on the decrease in mud-enriched sediments and the increase in fine and medium sand, whereas brightness loss and color alteration are related to the increase in fine and medium sand, as well as margin modification. Corrosion was positively correlated to the mud-dominated fraction. • Dense concentrations of bivalve shells occur in the bay and lagoon facies association. • Allochthonous and parautochthonous bivalve shell concentrations were differentiated. • In bay FA, the loss of periostracum positively correlates to fine sand. • In the lagoon FA, corrosion was positively correlated to mud-dominated sediments. • Gradients of medium sand and fine sand correlated to corrosion and abrasion. [ABSTRACT FROM AUTHOR]

The proboscidean Notiomastodon platensis is widely recognized in the Pleistocene of Brazil, but direct evidence for its feeding behavior is scant. In this paper, we report palynological assemblages preserved in dental calculi to infer dietary preferences and habitats. Molar specimens (m1 and M3/m3) with significant calculus accumulation were examined from localities along the Coastal Plain (CPRS) and the Campanha region (western state in Pampa biome) in Rio Grande do Sul state, southern Brazil. Palynomorphs obtained from calculus were identified with light microscopy, and we applied species distribution modelling (SDM) for arboreal/shrub pollen taxa to investigate the environmental contexts for proboscideans during the Last Interglacial (LIG, 120 ka BP) and Last Glacial Maximum (LGM, 21 ka BP). Pollen assemblages indicate a generalist diet for N. platensis , and corroborate previous paleoecological studies. N. platensis from CPRS showed two patterns: the subadult individual was a specialized browser in wooded habitats, inferred from pollen taxa dominated by arboreal species (mainly Myrtaceae), while mature/senile adult individuals were dominantly grazers to mixed-feeders in open habitats inferred from herbaceous pollen (mainly Cyperaceae) mixed with woody elements. For the Campanha region, diet interpretation is difficult due to the absence of pollen; however, Poaceae phytoliths indicate that grasses may have been important food items, notably pooid C 3 grasses. N. platensis potentially accessed a more heterogeneous environment with mixed open grasslands and forests around the LIG interval because of the larger extension of forest at the time. Grassland landscapes could have been more foraged by proboscideans around the LGM given the dry and cold climate conditions, which resulted in a northward retraction of forest. • Palynological analysis of dental calculus is used to infer the paleodiet of Pleistocene proboscideans from southern Brazil; • Individuals of different age class had distinct feeding behaviors and/or habitats; • Species distribution modellings suggest distinct environmental landscapes for the proboscideans home ranges; • Grasslands/forests and open grasslands were accessed during the Last Interglacial and Last Glacial Maximum, respectively. [ABSTRACT FROM AUTHOR]

The Paraná Basin, the largest basin in South America, received glacially derived sediments during the Late Palaeozoic Ice Age (LPIA) of the Gondwana supercontinent. Despite the importance of this basin for understanding the continental development of the Gondwana glaciation, and the fact that ca. 95% of this basin is not exposed at the surface, few attempts have been made to connect the exposed glacial strata to the subsurface record. In this paper, exposures of glacial cycles in the Upper Itararé Group in Santa Catarina State, southern Brazil, are analyzed, locally correlated and then linked to the three major glacial cycles previously described from subsurface studies along the basin. Together study areas (Doutor Pedrinho and Vidal Ramos) record five, partially comparable shorter glacial subcycles (relative to the major glacial cycles). These series comprise coarse-grained subaqueous outwash deposits, turbidite sand sheets, marine shales, and diamictites, the latter mostly derived from delta slope failure and ensuing resedimentation. In addition to sedimentological and genetic stratigraphic description and analysis, preliminary age determination based on the palynological content is also presented. Besides, a regional correlation of the described succession to the subsurface record is proposed based on well logs and core information. All the palynomorph associations identified from the exposed successions, which represent the upper third part of the Itararé Group, are related to the Subzone Protohaploxypinus goraiensis , base of the Vittatina costabilis Zone. This zone and correlated ones along the Gondwana are considered Early Permian in age. However, a first isotopic age recently obtained for the upper Itararé Group and published elsewhere is considered within a regional stratigraphic framework once it leads to new insights in terms of the LPIA time span recorded in the Paraná Basin. • Late Palaeozoic glacial cycles in western Gondwana • Correlation of long and short-term glacial cycles • Palynology of the upper Itararé group • Sequence stratigraphy of glacially-related successions [ABSTRACT FROM AUTHOR]