Southeastern South America Research Articles

<p><strong>A new subspecies<em> </em>of <em>Jodina rhombifolia</em> (Santalales: Cervantesiaceae), with taxonomical considerations</strong></p>

The monotypic genus Jodina is endemic from central to south-eastern South America, where it grows from southern Bolivia and Brazil, Uruguay, to northern and central Argentina. The only species included in the genus is Jodina rhombifolia, a small hemiparasitic tree about 4–8 m high that is characteristic of the chacoan environments of the Neotropical region and Monte from the South American transition zone. As part of the floristic updates in the Neotropical and Andean regions of South America, the nomenclature of taxa related to Jodina rhombifolia was re-examined. Owing to the morphological and anatomical differences observed, and the well-delimited geographical distribution patterns that suggest the existence of two distinguishable subspecific entities, a new subspecies of Jodina rhombifolia is proposed here. Two lectotypes are designated and the nomenclature is clarified. An identification key, complete descriptions of the taxa and geographical distribution of the subspecies are also provided.

118 years of ornithological knowledge of a forgotten region of the Atlantic Forest near the largest city in South America

The Atlantic Forest in eastern South America harbors 849 bird species, of which 216 are endemic and 122 threatened with extinction. It is also one of the 25 biodiversity hotspots recognized throughout the world. Within this biome, the Serra do Mar stands out as an important area of endemism in South America. Nonetheless, ornithological knowledge of the Serra do Mar remains underestimated and incomplete. One lacunae of information for the Serra is a region called Curucutu, which is adjacent to the largest urban area in South America. The avifauna of Curucutu has been sampled occasionally since 1900, but all of the available data have yet to be published. Therefore, we compiled ornithological data published on Serra do Mar over the last 118 years and undertook a 16-year-long field inventory using 3 methods of data collection simultaneously (visual observations, point counts, and mist nets) for a total of 395 field days. Sampling was performed in forest and natural grasslands along an elevational gradient from 5 to 850 m.a.s.l. A total of 422 species of birds, 128 of which are endemic to the Atlantic Forest and 29 that are threatened with extinction, were documented, thereby illustrating the importance of this region. Of this total, 382 species occur in Núcleo Curucutu do Parque Estadual da Serra do Mar, demonstrating the importance of this reserve to the regional avifauna. We made several significant additions to the avifauna of the region, with only one species, the Black-necked Aracari (Pteroglossus aracari), being considered regionally extinct because of a lack of records since 1900—thus representing a kind of poorly studied extinction that has yet to be investigated and may be happening with much greater frequency in large forested areas of Serra do Mar. Even though the region is partially protected, being a state reserve, its proximity to the largest urban area in South America automatically puts the area under threat, especially considering the disorganized urban growth that has been encroaching upon natural areas of the region. The expansion of current reserves, and the establishment of new protected areas in this region of Serra do Mar is essential for guaranteeing the integrity of this very rich and threatened bird community of the Atlantic Forest.

Global patterns and trends in ovarian cancer incidence: age, period and birth cohort analysis

BackgroundOvarian cancer (OC) is the seventh most common malignancy worldwide and the most lethal gynaecological malignancy. We aimed to explore global geographical patterns and temporal trends from 1973 to 2015 for 41 countries in OC incidence and especially to analyse the birth cohort effect to gain further insight into the underlying causal factors of OC and identify countries with increasing risk of OC.MethodsOC data were drawn from the Cancer Incidence in Five Continents databases and online databases published by governments. The joinpoint regression model was applied to detect changes in OC trends. The age–period–cohort model was applied to explore age and birth cohort effects.ResultsThe age-standardized rate of OC incidence ranged from 3.0 to 11.4 per 100,000 women worldwide in 2012. The highest age-standardized rate was observed in Central and Eastern Europe, with 11.4 per 100,000 women in 2012. For the most recent 10-year period, the increasing trends were mainly observed in Central and South America, Asia and Central and Eastern Europe. The largest significant increase was observed in Brazil, with an average annual percentage change of 4.4%. For recent birth cohorts, cohort-specific increases in risk were pronounced in Estonia, Finland, Iceland, Lithuania, the United Kingdom, Germany, the Netherlands, Italy, Malta, Slovenia, Bulgaria, Russia, Australia, New Zealand, Brazil, Costa Rica, Ecuador, India, Japan, the Philippines and Thailand.ConclusionsDisparities in the incidence and risk of OC persist worldwide. The increased risk of birth cohort in OC incidence was observed for most countries in Asia, Central and Eastern Europe, and Central and South America. The reason for the increasing OC risk for recent birth cohorts in these countries should be investigated with further epidemiology studies.

Effects of climate and geography on spatial patterns of genetic structure in tropical skinks

Knowledge of how contemporary and historical factors drive patterns of genetic structure across geographic space can shed light on the processes underlying diversification. This approach is especially fruitful in studies of widespread species or species clades that occur across multiple environmental conditions and biomes. In the Neotropics, specifically, molecular data from widespread vertebrate species have revealed high levels of lineage diversity and spatial genetic structure – yet studies that explore the possible correlates of local structure patterns are lacking. We investigate the distribution of lineage diversity within two widespread South American skink species complexes of the genus Mabuya. We characterize genetic structure and diversity in these widely ranged lizards, and identify potential geographic and environmental correlates, to shed light on the processes that promote lineage diversification across the heterogeneous landscapes which they occupy. In both groups, we found mitochondrial lineages to be spatially structured along the coastal forests and the savannas of Brazil. These mtDNA patterns are, however, not shared with those inferred from nuclear DNA markers. The geographic location of major mitochondrial genetic breaks is consistent with those of other taxa, suggesting common responses to former landscape change in eastern South America, particularly along geological faults. Genetic differentiation is correlated with environmental turnover and geographic separation in one, but not in the other, group of skinks. Compared to other studies of similarly widely distributed organisms, the link between spatial environmental gradients and genetic differentiation is not as strong or consistent, suggesting a more complex history underlying current phylogeographic patterns. Our genetic data indicate the existence of yet undescribed diversity in wide-ranging lizards, and the value of phylogenetic and phylogeographic studies of similarly understudied species.

A new mechanism for millennial scale positive precipitation anomalies over tropical South America

Continental and marine paleoclimate archives from northwestern and northeastern South America recorded positive precipitation anomalies during Heinrich Stadials (HS). These anomalies have been classically attributed to enhanced austral summer (monsoon) precipitation. However, the lack of marine paleoclimate records off eastern South America as well as inconsistencies between southeastern South American continental and marine records hamper a comprehensive understanding of the mechanism responsible for (sub-) tropical South American hydroclimate response to HS. Here we investigate piston core M125-95-3 collected off eastern South America (10.94°S) and simulate South American HS conditions with a high-resolution version of an atmosphere-ocean general circulation model. Further, meridional changes in precipitation over (sub-) tropical South America were assessed with a thorough compilation of previously available marine paleorecords. Our ln(Ti/Ca) and ln(Fe/K) data show increases during HS6-Younger Dryas. It is the first core off eastern South America and the southernmost from the Atlantic continental margin of South America that unequivocally records HS-related positive precipitation anomalies. Based on our new data, model results and the compilation of available marine records, we propose a new mechanism for the positive precipitation anomalies over tropical South America during HS. The new mechanism involves austral summer precipitation increases only over eastern South America while the rest of tropical South America experienced precipitation increases during the winter, challenging the widely held assumption of a strengthened monsoon. South American precipitation changes were triggered by dynamic and thermodynamic processes including a stronger moisture supply from the equatorial North Atlantic (tropical South Atlantic) in austral winter (summer).

Mortuary Pottery and Sacred Landscapes in Complex Hunter-gatherers in the Paraná Basin, South America

Tubular pottery comprises certain peculiar artifacts that were produced by late Holocene complex hunter-gatherer societies in southeastern South America for unknown purposes. Some authors have related them to mortuary behaviour which has also been suggested by historical sources, while others have considered domestic use. In this paper, the technical, compositional and functional properties of these artifacts are explored in order to contrast both hypotheses, given an example of how technical analysis allows the identification of special pottery within archeological contexts. This analysis includes a study of the fabrics involved using low and high magnification, thin sections, Scanning Electron Microscopy, Energy Dispersive X-ray Spectroscopy, Mössbauer Spectroscopy, Laser Induced Breakdown Spectroscopy and fatty acid profiles. The results show that these tubular artifacts are not fit structurally for utilitarian purposes and show no evidence of domestic use. Based on these results and on historical data, it can be postulated that they were used as part of mortuary rituals, thus becoming part of the select global group of pottery manufactured exclusively for mortuary purposes.

Aridity, soil and biome stability influence plant ecoregions in the Atlantic Forest, a biodiversity hotspot in South America

Our aims were to quantify and map the plant ecoregions of the Atlantic Forest, a biodiversity hotspot that covers ca 150 million ha in eastern South America. We used a data set on the distribution of 4378 shrub and tree species across 711 localities. Plant ecoregions were identified using analyses of species turnover for both species occurrences and relative abundances. We interpolated NMDS axes of compositional variation over the entire the Atlantic Forest extent, and then classified the compositional dissimilarity according to the number of biogeographical ecoregions previously identified through K‐means analyses. We assessed the ability of environmental, historical vegetation stability and the current human footprint to explain the occurrence of the identified ecoregions through multinomial logistic regression models. We identified 21 spatially cohesive occurrence and 14 abundance ecoregions. Aridity, soil and historical biome stability were retained in the best model explaining both occurrence and abundance ecoregions. Broad compositional zones were identified through UPGMA cluster analysis of ecoregions, and formed north and south compositional blocks. Our work confirms the existence of a broad north–south divide within the Atlantic Forest, previously suggested based on climatic and amphibious data. Differences between the occurrence and abundance maps suggest the location of transition zones to neighbouring domains and endemism centres. Due to the aggregate nature of our analyses, site‐level disturbance degree was not considered, implying that human impacts could be broader then we could detect. There was limited overlap between our results and previous Atlantic Forest regionalization efforts, indicating that multi‐taxa, physiognomic and environmental regionalization schemes based on expert opinion or vegetation maps are poor proxies for compositional ecoregions.

Autecology of Kentropyx calcarata (Squamata: Teiidae) in a Remnant of Atlantic Forest in Eastern South America

Abstract Kentropyx calcarata is a widely foraging teiid lizard species that inhabits forest environments east of the Andes in South America. We studied the ecology of a K. calcarata population in a...

A comparison of bird communities in natural and revegetated grasslands in south Brazil

Natural grasslands are declining due to loss, fragmentation and degradation, resulting in the decline of grassland-associated bird species. The Pampas Biome in south Brazil is not exception to this worldwide trend, facing the expansion of croplands and afforestation with exotic tree plantations for cellulose production. To cope with the continuous degradation and loss of grasslands, restoration is an important conservation strategy, but basic information regarding the response of the fauna to restoration practices in southeastern South America grasslands is lacking. Here we compared the structure of bird communities in natural grasslands and revegetated grasslands after mining by planting native and exotic grasses. We sampled birds using 5-min point counts with unlimited radius in three replicates of each habitat (natural and revegetated grasslands; average size 22.2 ± 2.3 ha). We also compared the vegetation density between the two habitat types. The structure of bird communities at natural and revegetated grasslands differed, with natural grasslands presenting higher species richness (42 vs. 35 species) and abundance (1459 vs. 839 records) than revegetated areas, and also a distinct species composition. Ten of the 11 grassland species that were associated to one of the two habitat types occurred more frequently in natural grasslands, which had higher vegetation density than revegetated areas. Even a decade after the beginning of the restoration process, revegetated areas did not resemble natural grasslands in bird species richness, abundance, and composition. These results differed from another study conducted in the Brazilian Pampas in which native plant species were used to actively restore a grassland. Therefore, until we have additional studies addressing the use of exotic grasses for the recovery of bird communities in South America grasslands, we encourage greater representation of native plant species in restoration projects.

Phylogenetic relationships and historical biogeography of Oligosarcus (Teleostei: Characidae): Examining riverine landscape evolution in southeastern South America

The pike-characin Oligosarcus is a group of Characidae composed of 22 species, which have mostly allopatric distributed species in southeastern South America and sympatric occurrence of few species. Oligosarcus shares a similar distribution pattern with other fish genera and therefore, can help us to understand biogeographic events that influenced freshwater fish distribution in the southeastern South America. Our paper presents the most extensive taxonomic coverage for molecular analysis of Oligosarcus and uses various methods to examine the evolutionary history of the genus. Phylogenetic relationships among species of Oligosarcus were examined using a multilocus dataset by Maximum Likelihood and Bayesian methods. A relaxed molecular clock was used to estimate lineage divergence times, which provide a framework to examine the biogeographic history of this clade across the drainage basins of southeastern South America. Oligosarcus was resolved as monophyletic with strong support, and related to lineages currently assigned to the genus Astyanax. Within Oligosarcus, two groups of approximately equal species richness were resolved as monophyletic, mainly restricted to continental and coastal drainages of southeastern South America. Oligosarcus radiation is estimated to the late Neogene, with its origin in the Pliocene and most speciation events occurring in the Pleistocene. Some apomorphic characteristics associated with piscivory (e.g. large caniniform teeth) in Oligosarcus likely have evolved once, and are convergent to similar phenotypes observed in a distantly related clade of Astyanax (formerly Bramocharax). In addition, the presence of morphological convergence within the genus Oligosarcus (e.g. trophic morphology) seems to explain the difference between the present molecular hypothesis and some previous morphological studies. Ancestral geographical range estimation using analytical methods (e.g. DIVALIKE and DEC) demonstrated the effects of different Landscape Evolution Models (LEMs) on diversification of Oligosarcus. The results suggest that the two main Oligosarcus clades evolved in allopatry in continental and coastal drainages, with subsequent range extension and vicariance events that established the modern distributions. LEM analyses indicate the importance of formation of riverine barriers across the watershed of the La Plata basin and the effects of sea-level changes during the Pleistocene for delineating lineage distributions of Oligosarcus.

Postrift stress field inversion in the Potiguar Basin, Brazil – Implications for petroleum systems and evolution of the equatorial margin of South America

Rifting and related normal stress regime in the equatorial continental margin of Brazil ceased during the Late Cretaceous, when the stress regimes in eastern South America and West Africa changed to induce strike-slip or reverse motion. In this study, we explore the postrift tectonic, geomorphic, magmatic, and sedimentary responses to stress changes using the Potiguar Basin, the easternmost basin in the equatorial margin of Brazil, as a case study. We use field and topographic data, 2D seismic reflection lines, vertical electric soundings, and geochronological and borehole data to constrain the stress evolution of the Potiguar Basin from the Late Cretaceous to the Quaternary, discussing the role of basin inversion on sedimentation and landforms. Our results indicate the presence of two strike-slip stress regimes after rifting. The first stress field (SF1) occurred from Late Cretaceous to the middle Miocene and consisted of a N-S-oriented maximum subhorizontal compression and an E-W-oriented extension. The second stress field (SF2) took place from the middle Miocene to the present day and included subhorizontal E-W to NW-SE compression combined with N-S and NE-SW subhorizontal extension. Emplacement of volcanic rocks occurred along transtensional faults, with a principal peak during SF1 at 20–30 Ma and a subordinate peak during SF2 at 5–10 Ma. In response to shortening during SF2, a 70-km-long and 50-km-wide dome formed, where marine Miocene strata were uplifted to ~250 m asl. This uplift induced the displacement of alluvial channels away from the dome. Anticlines formed by transpression along the main NE-SW-striking faults during both SF1 and ST2 acted as traps in the petroleum system. Similar shifts and stress field inversions documented in other areas of the Brazilian continental margin are consistent with the Neogene rise of the Andes and may have implications for reconstructing the tectonic history of the Equatorial Atlantic margin of South America.

Río Uruguay. Una síntesis arqueológica

La cuenca del río Uruguay se extiende a través de Brasil, Argentina y Uruguay y es una de las redes fluviales fundamentales para la ocupación humana del sudeste de Sudamérica. Desde sus nacientes hasta su desembocadura y desde el Pleistoceno final hasta la actualidad, este río presenta evidencias arqueológicas y etnohistóricas de ocupaciones indígenas. En este marco, este artículo constituye una síntesis regional de la historia de estas ocupaciones y del desarrollo de las investigaciones arqueológicas en los tres países mencionados. Primero, se expone el contexto ambiental y los estudios arqueológicos realizados. Posteriormente, se presentan los sitios arqueológicos y los artefactos más relevantes para la transición Pleistoceno-Holoceno, Holoceno temprano y Holoceno medio. Por último, se caracteriza el registro arqueológico Taquara-Itararé, Goya-Malabrigo y guaraní correspondiente al Holoceno tardío. La información presentada permite reconocer al río Uruguay y sus afluentes como el escenario de una compleja dinámica poblacional, caracterizada por la articulación de un gran número de poblaciones, cultural y lingüísticamente diversas, durante más de 12.000 años.

The effects of grassland ecosystem afforestation on avian phylogenetic diversity, taxonomic diversity and evolutionary distinctiveness

Forest plantations are among the main threats to the grassland ecosystems of southeastern South America. One key question is whether such plantations affect the evolutionary diversity of bird communities, since previous studies have shown a reduction in taxonomic and functional diversity. High levels of phylogenetic diversity can ensure the conservation of communities, and high evolutionary potential to adapt to environmental changes. Taking this into account we investigated whether the conversion of native grasslands into forest plantations impacted the evolutionary and taxonomic diversity of bird communities, through an analysis of the different dimensions of diversity. Our investigations took place in southern Brazil where native grasslands predominate, however many have been afforested in recent years. We collected data from bird communities in native grassland and forest habitats, as well as from eucalyptus plantations. Our results did not detect a reduction in phylogenetic diversity in the planted areas but did demonstrate the taxonomic impoverishment of bird communities. Furthermore, we registered a reduction in the evolutionary distinctiveness of bird communities in forest plantations and a variation of phylogenetic composition among habitats. This indicates the evolutionary adaptations of species to their habitat, whether it is forest or grassland. Riparian forest lineages appeared more capable of colonizing forest plantations, while grassland lineages appeared unfit to do so. Afforestation of grassland ecosystems may represent a future threat to the maintenance of evolutionarily distinct bird species, as well as to strict grassland species which have been shown to be evolutionarily unable to colonize forest plantations. We recommend the maintenance of forest plantations only in areas that have already been converted or degraded. Additionally, we emphasize the importance of practicing non-intensive economic activities in these areas, for example, cattle production in low-intensity. Such activities in low-intensity have been shown to be beneficial for the maintenance of the evolutionary and taxonomic diversity of bird communities.

Coherent South American Monsoon Variability During the Last Millennium Revealed Through High‐Resolution Proxy Records

AbstractThe number of paleoprecipitation records from the South American Monsoon domain that cover the last millennium has increased substantially in past years. However, hitherto most studies focused only on regional aspects, thereby neglecting the role of large‐scale monsoon variability and the mechanisms that link proxy locations in space and time. Here we decompose the South American Monsoon into its main modes of variability by applying a Monte Carlo principal component analysis to a compilation of 11 well‐dated summer paleoprecipitation records from tropical South America. The first mode represents changes in precipitation over the core monsoon domain, while the second mode is characterized by high loadings along the fringes of the South American Monsoon over Southeastern South America and the northern monsoon limit. Composite analysis reveals an enhanced monsoon with a wider, rather than a southward displaced, South Atlantic Convergence Zone during the early Little Ice Age, in contrast to previous interpretations.

Common cause for severe droughts in South America and marine heatwaves in the South Atlantic

In 2013/14 eastern South America experienced one of its worst droughts. At the same time an unprecedented marine heatwave developed in the western South Atlantic. The drought was linked to suppression of the South Atlantic convergence zone and its associated rainfall, which led to water shortages in Brazil and impacted food supplies globally. Here we show from observations that such droughts and adjacent marine heatwaves have a common remote cause. Atmospheric blocking triggered by tropical convection in the Indian and Pacific oceans can cause persistent anticyclonic circulation that not only leads to severe drought but also generates marine heatwaves in the adjacent ocean. We show that increased shortwave radiation due to reduced cloud cover and reduced ocean heat loss from weaker winds are the main contributors to the establishment of marine heatwaves in the region. The proposed mechanism, which involves droughts, extreme air temperature over land and atmospheric blocking explains approximately 60% of the marine heatwave events in the western South Atlantic. We also identified an increase in frequency, duration, intensity and extension of marine heatwave events over the satellite period 1982–2016. Moreover, surface primary production was reduced during these events with implications for regional fisheries. Droughts in South America and marine heatwaves in the South Atlantic have a common remote cause, convection in the tropical oceans that triggers atmospheric blocking, suggest analyses of observations.

Cutaneous larva migrans - a case report in amplas community health centre, Medan

Cutaneous Larva Migrans (CLM) is one of the most helminthic skin infestations, frequently in tropics and subtropics countries, including Southeastern United States, Central, and South America, Southeast Asia, and Africa. The infected cats and dogs usually defecate in sandpits, seashore, or areas with loose, wet soils where also being the natural environments for the larvae. Human is the dead-end hosts that the filariform larvae in humans are not capable of maturation. The larvae keep moving approximately 2 – 3 cm/day. During its migration, an itchy erythematous. CLM is a self-limiting disease, the spontaneous resolution coming up within a few weeks. But most patients used to receive anti-parasite therapy, such as Albendazole or Ivermectin.

A paleoclimatic reconstruction of the Carboniferous-Permian paleovalley fill in the eastern Paganzo Basin: Insights into glacial extent and deglaciation of southwestern Gondwana

During the mid-Carboniferous, ice centers located in present-day western Argentina disappeared until the late Cenozoic with glaciation of the Andes. The disappearance of mid-Carboniferous glaciers and the subsequent climate shift, recorded in the Paganzo Basin, has been attributed to global events and drivers, such as increased atmospheric CO2 concentrations and the shifting position of Gondwana across the South Pole. However, glaciers continued at the same paleolatitude in eastern South America and did not disappear from Gondwana until the Late Permian. This study investigates links to local drivers that acted in combination with other global drivers to explain the early deglaciation along the western margin of Gondwana. To do this, several outcrops within the eastern portion of the Paganzo Basin in western Argentina were sampled for the Chemical Index of Alteration (CIA) geochemical analyses. Here, we test the applicability of the CIA as a paleoclimate proxy on strata in the Olta-Malanzán paleovalley that historically was thought to have been glaciated. A recent study by the authors has shown that the paleovalley was not glaciated, but owes its origin to extension and excavation by fluvial processes. However, the late Paleozoic stratigraphy of this paleovalley system is similar to the rest of the Paganzo Basin. The results from the paleovalley samples show that this area was intermittently humid and arid through time, but with an overall arid profile. This signature is predominantly due to the nature of the paleovalley, which was subjected to rapid burial from frequent rock falls, progradation alluvial fans/fan deltas, and lacustrine sediment gravity flows (Malanzán Fm.), which prevented any significant chemical weathering. While the overall Pennsylvanian climatic signature appears to be relatively arid (Malanzán, Loma Larga, and Solca Fms.), it seems that the climate during the deposition of the late Pennsylvanian and Permian La Colina Formation was more humid than previously thought.

Intraseasonal modulation of spring‐strong wind events associated with convection in northeastern Argentina

AbstractThe relationship between intraseasonal variability (IS; 10–90 days) and days which registered convection‐associated strong surface wind events (CSSWE) over northeastern Argentina (NEA) was studied. The climatological behaviour of these strong wind events showed a higher duration and occurrence in austral spring. CSSWE were categorized as a function of the wet and dry phases of the spring‐season intraseasonal (spring‐SIS) index, which describes the activity of the leading pattern of IS‐filtered outgoing longwave radiation (IS‐OLR) during that season in eastern South America. A modulation of the IS variability over localized and mesoscale phenomena as the CSSWE was found, showing significant peaks of wind variability in that timescale, and especially the submonthly timescale. The CSSWE were categorized according to the phases of the spring‐SIS pattern and most of them occurred before or during a wet phase, especially for the longer CSSWE. Moreover, the detection of CSSWE days during and before a dry phase was scarce. Rossby wave trains were observed to organize the circulation on intraseasonal timescales that configure regional cyclonic anomalies in such way that favours the development of CSSWE, promoting mid‐level ascents over NEA and northerly advection of humidity to the region. Together with the composites of IS‐OLR anomalies and the spectra of wind velocity, they support the fact that the higher‐frequency IS variability is the primary influence for the development of CSSWE.

Impacto Mês a Mês do Modo Anular Sul na América do Sul

The goal of this paper is to study month-to-month impacts of Southern Hemisphere Annular Mode (SAM) phases over South America (SA). Composite analyses were performed excluding ENSO years. Southeastern SA (SESA), part of Southeastern and Central-West of Brazil seem to be more affected by SAM. However, SAM influences are different for each month, and there are also differences of the influences between SAM phases (not always opposite). For air temperature, March, May, July, August, September, and November show positive (negative) anomalies affecting regions cited above during the negative (positive) SAM phase. Although, the coverage of these anomalies is different among these months. February and December present a temperature anomaly dipole, with positive (negative) anomaly at SESA and negative (positive) northward, in the negative (positive) SAM phase. January has a different behavior compared with other months but also presents a nearly opposite signal between SAM phases. Precipitation anomalies composites indicate a weakening (strengthening) of South Atlantic Convergence Zone configuration at negative (positive) SAM phase (November-January and March). SESA region shows positive (negative) precipitation anomalies at negative (positive) SAM phases, during March-June and December. Nevertheless, in October, SAM oppositely influences this region. A case study (January 2017 - negative SAM - neutral ENSO) shows great similarity with the precipitation composites, ratifying the results. However, for temperature, the coastal region is the only which presents similarity with the composites.

Outstanding plant endemism levels strongly support the recognition ofcampo rupestreprovinces in mountaintops of eastern South America

AbstractAimThe Braziliancampo rupestreis a vegetation associated to ancient mountaintops in eastern South America, spread mainly over disjunct areas of the Espinhaço Range and the Chapada dos Veadeiros. These areas hold outstanding levels of plant diversity and endemism, but despite their uniqueness they have been neglected in recent bioregionalizations for the Neotropical region. Given their particular levels of species richness and endemism, we here test the recognition of these as distinct bioregions within the Chacoan dominion.LocationMountaintops of eastern South America.MethodsWe listed 1,748 angiosperm species endemic to thecampo rupestreof the Espinhaço Range and Chapada dos Veadeiros regions, based on the data gathered from the Brazilian Flora 2020 Project. We extracted all occurrence information available from GBIF (the Global Biodiversity Information Facility) for such list and also for a polygon gathering all the study area, including information from adjacent vegetations. Data went through standard cleaning procedures and a network clustering analysis was performed to delimitate the boundaries of the new bioregions.ResultsOur data strongly support the recognition of two distinct bioregions along the Espinhaço Range, but none in the Chapada dos Veadeiros. Given their high levels of endemism and singularity within the Chacoan dominion, we formalize two provinces associated tocampo rupestrein the Espinhaço Range, naming them as “Chapada Diamantina” and “Southern Espinhaço” provinces. Within the latter province, three districts are also recognized, based on this and previous studies: “Diamantina Plateau”, “Grão‐Mogol” and “Iron Quadrangle” districts.Main conclusionsThe formalization of new and previously described bioregions highlights thecampo rupestreas a vegetation harbouring outstanding levels of species richness and endemism in South America, contributing to a better understanding of biogeographical patterns in the Neotropics. Also, as we follow the International Code of Area Nomenclature as a device to standardize recognition of bioregions, this shall facilitate further biogeographical and conservation studies in these areas. Further assessments with new and revisited data are needed to enable minor scale bioregionalization within the Chacoan dominion.