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Biotic and abiotic factors play a crucial role in determining the distribution of species. These factors dictate the conditions that must be met for a species to thrive in a particular area. Sister species that present some degree of niche overlap can shed light on how they are distributed and coexist in their environment. This study aims to investigate the geographical distribution and ecological niche of the sister species of snake-necked turtles Hydromedusa maximiliani and H. tectifera. By analyzing their niche overlap, we aim to obtain a better understanding of how these two species coexist and which variables are determining their occurences. We applied species distribution modeling and compared the niches using the niche equivalence and similarity tests. Our findings show that the distribution of H. maximiliani is most influenced by temperature seasonality and isothermality, while H. tectifera is most affected by the temperature seasonality, precipitation of warmest quarter and mean diurnal range. In addition, our results suggest that the niche expressed by H. maximiliani retained ecological characteristics that can accurately predict the H. tectifera distribution, but the inverse is not true. In this sense, differences are not solely due to the geographic availability of environmental conditions but can reflect niche restrictions, such as competition.

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Camera traps became the main observational method of a myriad of species over large areas. Data sets from camera traps can be used to describe the patterns and monitor the occupancy, abundance, and richness of wildlife, essential information for conservation in times of rapid climate and land-cover changes. Habitat loss and poaching are responsible for historical population losses of mammals in the Atlantic Forest biodiversity hotspot, especially for medium to large-sized species. Here we present a data set from camera trap surveys of medium to large-sized native mammals (>1 kg) across the Atlantic Forest. We compiled data from 5380 ground-level camera trap deployments in 3046 locations, from 2004 to 2020, resulting in 43,068 records of 58 species. These data add to existing data sets of mammals in the Atlantic Forest by including dates of camera operation needed for analyses dealing with imperfect detection. We also included, when available, information on important predictors of detection, namely the camera brand and model, use of bait, and obstruction of camera viewshed that can be measured from example pictures at each camera location. Besides its application in studies on the patterns and mechanisms behind occupancy, relative abundance, richness, and detection, the data set presented here can be used to study species' daily activity patterns, activity levels, and spatiotemporal interactions between species. Moreover, data can be used combined with other data sources in the multiple and expanding uses of integrated population modeling. An R script is available to view summaries of the data set. We expect that this data set will be used to advance the knowledge of mammal assemblages and to inform evidence-based solutions for the conservation of the Atlantic Forest. The data are not copyright restricted; please cite this paper when using the data.

As armadilhas fotográficas tornaram­se o principal método de observação de muitas espécies em grandes áreas. Os dados obtidos com armadilhas fotográficas podem ser usados para descrever os padrões e monitorar a ocupação, abundância e riqueza da vida selvagem, informação essencial para a conservação em tempos de rápidas mudanças climáticas e de cobertura do solo. A perda de habitat e a caça furtiva são responsáveis pelas perdas populacionais históricas de mamíferos no hotspot de biodiversidade da Mata Atlântica, especialmente para espécies de médio e grande porte. Aqui apresentamos um conjunto de dados de levantamentos com armadilhas fotográficas de mamíferos de médio e grande porte (>1 kg) em toda a Mata Atlântica. Compilamos dados de 5.380 armadilhas fotográficas instaladas no nível do chão em 3.046 locais, de 2004 a 2020, resultando em 43.068 registros de 58 espécies. Esses dados acrescentam aos conjuntos de dados existentes de mamíferos na Mata Atlântica por incluir as datas de operação das câmeras, que são necessárias para análises que lidam com detecção imperfeita. Também incluímos, quando disponíveis, informações sobre importantes preditores de detecção, como marca e modelo da câmera, uso de isca e obstrução do visor da câmera que pode ser medido a partir de imagens de exemplo em cada local da câmera. Além de estudos sobre os padrões e mecanismos por trás da ocupação, abundância relativa, riqueza e detecção, o conjunto de dados aqui apresentado pode ser usado para estudar os padrões de atividade diária das espécies, nível de atividade e interações espaço­temporais entre as espécies. Além disso, os dados podem ser usados em combinação com outras fontes de dados em diversas análises com modelagem populacional integrada. Um script R está disponível para visualizar um resumo do conjunto de dados. Esperamos que este conjunto de dados seja usado para aumentar o conhecimento sobre as assembleias de mamíferos e usado para informar soluções baseadas em evidências para a conservação da Mata Atlântica. Os dados não são restritos por direitos autorais e, por favor, cite este documento ao usar os dados.

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Mountains harbor a significant number of the World's biodiversity, both on tropical and temperate regions. Notably, one crucial gap in conservation is the consideration of historical and contemporary patterns influencing differential distribution in small mammal mountain species and how climate change will affect their distribution and survival. The mice Peromyscus mexicanus species group is distributed across mountains in Guatemala-Chiapas and Central America, which experienced significant effects of glacial and interglacial cycles. We determined phylogeographic and demographic patterns of lowlands and highlands mountain lineages, revealing that the radiation of modern P. mexicanus lineages occurred during the Pleistocene (ca. 2.6 mya) along Nuclear Central America. In concert with climatic cycles and the distribution of habitats, lowland and highland lineages showed recent population size increase and decrease, respectively. We also estimated the current and future distribution ranges for six lineages, finding marked area size increase for two lineages for which vegetation type and distribution would facilitate migrating towards higher elevations. Contrastingly, three lineages showed range size decrease; their ecological requirements make them highly susceptible to future habitat loss. Our findings are clear evidence of the negative impacts of future climate change, while our ability to manage and conserve these vulnerable ecosystems and mountain species is contingent on our understanding of the implications of climate change on the distribution, ecology, and genetics of wildlife populations.

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Pilocarpus microphyllus Stapf. ex Wardlew. (Rutaceae) is an endemic and threatened medicinal plant species from tropical Brazil. Popularly known as "jaborandi", it is the unique natural source of pilocarpine, an alkaloid used to medical treat glaucoma and xerostomia. Based on Species Distribution Models (SDMs), we modeled the suitability of P. microphyllus's geographical distribution considering three Global Circulation Models (GCMs) under two future climate change scenarios (SSP2-4.5 and SSP5-8.5). The quantitative analyses carried out using ten different SDM algorithms revealed that precipitation seasonality (Bio15) and precipitation of the driest month (Bio14) were the most important bioclimatic variables. The results evidenced four main key areas of continuous occurrence of the plant spreading diagonally over tropical Brazilian biomes (Amazon, Cerrado and Caatinga). The near-future (2020 to 2040) ensemble projections considering all GCMs and scenarios have indicated negative impacts for the potential loss or significant reduction in suitable habitats for P. microphyllus in the transition region between the Amazon and Cerrado into central and northern Maranhão state, and mainly in the Caatinga biome over the northern Piaui state. On the other hand, positive impacts of the expansion of the plant habitat suitability are projected over forest cover protected areas of the Amazon biome in the southeastern Pará state. Since the jaborandi is of socioeconomic importance for many families in the north/northeast Brazil, it is urgent to implement public policies for conservation and sustainable management, thus mitigating the impacts of global climate change.

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Refugia-based conservation offers long-term effectiveness and minimize uncertainty on strategies for climate change adaptation. We used distribution modelling to identify climate change refugia for 617 terrestrial mammals and to quantify the role of protected areas (PAs) in providing refugia across South America. To do so, we compared species potential distribution across different scenarios of climate change, highlighting those regions likely to retain suitable climatic conditions by year 2090, and explored the proportion of refugia inside PAs. Moist tropical forests in high-elevation areas with complex topography concentrated the highest local diversity of species refugia, although regionally important refugia centers occurred elsewhere. Andean-Amazon forests contained climate change refugia for more than half of the continental species' pool and for up to 87 species locally (17 × 17 km2 grid cell). The highlands of the southern Atlantic Forest also included megadiverse refugia for up to 76 species per cell. Almost half of the species that may find refugia in the Atlantic Forest will do so in a single region-the Serra do Mar and Serra do Espinhaço. Most of the refugia we identified, however, were not in PAs, which may contain <6% of the total area of climate change refugia, leaving 129-237 species with no refugia inside the territorial limits of PAs of any kind. Our results reveal a dismal scenario for the level of refugia protection in some of the most biodiverse regions of the world. Nonetheless, because refugia tend to be in high-elevation, topographically complex, and remote areas, with lower anthropogenic pressure, formally protecting them may require a comparatively modest investment.

Identificación de refugios para la biodiversidad de Sudamérica ante el cambio climático Resumen Las estrategias de conservación basadas en refugios ofrecen efectividad a largo plazo y minimizan la incertidumbre sobre las estrategias de adaptación al cambio climático. Utilizamos modelos de distribución para identificar los refugios del cambio climático de 617 especies de mamíferos terrestres y cuantificar el papel de las áreas protegidas en la provisión de refugios en Sudamérica. Para esto, comparamos la distribución potencial de las especies en diferentes escenarios de cambio climático, destacando las regiones que probablemente conservarán las condiciones climáticas adecuadas para el año 2090, y exploramos la proporción de refugios dentro de las áreas protegidas. Los bosques tropicales húmedos de zonas de gran altitud y topografía compleja concentraron la mayor diversidad local de refugios de especies, aunque también hubo centros de refugio de importancia regional en otras localidades. Los bosques amazónicos andinos albergaron los refugios ante el cambio climático de más de la mitad del conjunto de especies continentales y para hasta 87 especies a escala local (celda cuadriculada de 17 × 17 km2 ). Las tierras altas del sur del Bosque Atlántico también incluyeron refugios megadiversos para hasta 76 especies por celda. Casi la mitad de las especies que pueden refugiarse en el Bosque Atlántico lo harán en una sola región: la Serra do Mar y la Serra do Espinhaço. Sin embargo, la mayoría de los refugios que identificamos no estaban en áreas protegidas, las cuales pueden contener <6% del área total de refugios del cambio climático, dejando entre 129 y 237 especies sin refugio dentro de los límites territoriales de las áreas protegidas de cualquier tipo. Nuestros resultados revelan un panorama desolador para el nivel de protección de los refugios en algunas de las regiones con mayor biodiversidad del mundo. No obstante, dado que los refugios suelen encontrarse en zonas remotas de gran altitud con topografía compleja y menor presión antropogénica, protegerlos formalmente puede requerir una inversión comparativamente modesta.

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Scirtothrips dorsalis Hood (Thysanoptera: Thripidae) is an invasive pest that is popularly known as chilli thrips. This insect pest has a wide range of hosts distributed across 72 plant families, causing damage to numerous crops of great economic importance. In the Americas, it is present in the USA, Mexico, Suriname, Venezuela, Colombia, and some Caribbean Islands. Knowing the regions which have environmentally suitable conditions for the survival of this pest is important for phytosanitary monitoring and inspection. Thus, our objective was to forecast the distribution potential of S. dorsalis with a focus on the Americas. Models were produced to design this distribution, in which the environmental variables used were made available in Wordclim version 2.1. The algorithms used for the modeling were the generalized additive model (GAM), generalized linear model (GLM), maximum entropy (MAXENT), random forest (RF), and Bioclim, in addition to the ensemble, which consisted of the grouping of the algorithms used. The metrics used to evaluate the models were area over the curve (AUC), true ability statistics (TSS), and Sorensen score. All models had satisfactory results (> 0.8) for all metrics used. In North America, the model showed favorable regions on the west coast of the USA and east coast near New York. In South America, the potential distribution of the pest is significant, encompassing regions in all countries. It is concluded that S. dorsalis has suitable areas for the occurrence in the three American subcontinents and, in particular, a large part of South America.

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The biogeographic region of Argentinean Puna mainly extends at elevations higher than 3,000 m within the Andean Plateau and hosts diverse ecological communities highly adapted to extreme aridity and low temperatures. Soils of Puna are typically poorly evolved and geomorphology is shaped by drainage networks, resulting in highly vegetated endorheic basins and hypersaline basins known as salar or salt flats. Local communities rely on soil fertility for agricultural practices and on pastures for livestock rearing. From this perspective, investigating the scarcely explored microbiological diversity of these soils as indicators of ecosystems functioning might help to predict the fragility of these harsh environments. In this study we collected soil samples from 28 points, following a nested design within three different macro-habitats, i.e., Puna grassland, hypersaline salar and family-run crop fields. Total fungi and arbuscular mycorrhizal fungi (AMF) occurrence were analyzed using eDNA sequencing. In addition, the significance of soil salinity and organic matter content as significant predictors of AMF occurrence, was assessed through Generalized Linear Mixed Modeling. We also investigated whether intensive grazing by cattle and lama in Puna grasslands may reduce the presence of AMF in these highly disturbed soils, driving or not major ecological changes, but no consistent results were found, suggesting that more specific experiments and further investigations may address the question more specifically. Finally, to predict the suitability for AMF in the different macro-habitats, Species Distribution Modeling (SDM) was performed within an environmental coherent area comprising both the phytogeographic regions of Puna and Altoandino. We modeled AMF distribution with a maximum entropy approach, including bioclimatic and edaphic predictors and obtaining maps of environmental suitability for AMF within the predicted areas. To assess the impact of farming on AMF occurrence, we set a new series of models excluding the cultivated Chaupi Rodeo samples. Overall, SDM predicted a lower suitability for AMF in hypersaline salar areas, while grassland habitats and a wider temperature seasonality range appear to be factors significantly related to AMF enrichment, suggesting a main role of seasonal dynamics in shaping AMF communities. The highest abundance of AMF was observed in Vicia faba crop fields, while potato fields yielded a very low AMF occurrence. The models excluding the cultivated Chaupi Rodeo samples highlighted that if these cultivated areas had theoretically remained unmanaged habitats of Puna and Altoandino, then large-scale soil features and local bioclimatic constraints would likely support a lower suitability for AMF. Using SDM we evidenced the influence of bioclimatic, edaphic and anthropic predictors in shaping AMF occurrence and highlighted the relevance of considering human activities to accurately predict AMF distribution.

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The Tropical Andes Biodiversity Hotspot holds a remarkable number of species at risk of extinction due to anthropogenic habitat loss, hunting, and climate change. One of these species, the critically endangered yellow-tailed woolly monkey (Lagothrix flavicauda), was recently observed in the region Junín, 206 km south of its previously known distribution. This range extension, combined with continued habitat loss, calls for a reevaluation of the species distribution, and available suitable habitat. Here, we present novel data from surveys at 53 sites in the regions of Junín, Cerro de Pasco, Ayacucho, and Cusco. We encountered L. flavicauda at 9 sites, all in Junín, and the congeneric Lagothrix lagotricha tschudii at 20 sites, but never in sympatry. Using these new localities along with all previous geographic localities for the species, we made predictive species distribution models based on ecological niche modeling using a generalized linear model and maximum entropy. Each model incorporated bioclimatic variables, forest cover, vegetation measurements, and elevation as predictor variables. The model evaluation showed >80% accuracy for all measures. Precipitation was the strongest predictor of species presence. Habitat suitability maps illustrate potential corridors for gene flow between the southern and northern populations, although much of this area is inhabited by L. l. tschudii whereas L. flavicauda has yet to be officially confirmed in these areas, by these or any other scientific surveys. An analysis of the current protected area (PA) network showed that ~75% of remaining suitable habitat is unprotected. With this, we suggest priority areas for new PAs or expansions to existing reserves that would conserve potential corridors between L. flavicauda populations. Further surveys and characterization of the distribution in intermediate areas, combined with studies on gene flow through these areas, are still needed to protect this species.

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Epicauta Dejean is one of the largest genera within Meloidae, with approximately 400 species identified to date. In this work, I applied the maximum entropy algorithm (Maxent) to predict the current and future distribution of this genus in America. A total of 12,130 points and 19 bioclimatic variables were used to model its potential distribution area under current and future climate scenarios. Maxent showed high prediction performance, and 7 out of the 19 variables used were found to be the most influential on the current and future distribution of Epicauta. It also allowed to predict the distribution of Epicauta in geographical areas where different bioclimatic criteria are combined. These areas belong to several provinces of the Nearctic, Neotropical regions and the Mexican and South American transition zones. Maxent also revealed that in North America, the current and future potential distribution of Epicauta is located within 38°N 97°W, while in South America, it is further south, within 25°S 60°W. According to this, it can be concluded that its greatest diversity is circumscribed to temperate and semi-arid regions, and that the tropical habitats of middle America have apparently served as effective barriers to faunal exchange since the intercontinental connection that occurred four million years ago until now. The findings from the present study provide a theoretical basis to better understand the distribution patterns of Epicauta spp. under changing climate conditions.

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The number of reports of tick parasitism in amphibians and reptiles has increased over the past few years, including new host and location records for Amblyomma rotundatum and Amblyomma dissimile. However, knowledge of the geographical distribution remains incomplete, and in many regions of Brazil, the presence of these vectors has not been investigated. Several candidate models were built using a correlative maximum entropy approach, and best-fitting models were selected based on statistical significance, predictive ability, and complexity based on current climatic trends and future projected climate changes. Final models showed a good ability to discriminate A. rotundatum and A. dissimile current and future potential distributions. The entire country had higher predicted suitability for A. rotundatum while A. dissimile was mainly restricted to the Amazon and Pantanal biomes. A. rotundatum is a species with enormous potential for dissemination in the next decades, potentially through the legal and illegal transport of reptiles and amphibians. The proposed model is useful for targeting surveillance efforts increasing the efficiency and accuracy of future ecological research and tick management efforts.

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Ecological niche models (ENMs) have classically operated under the simplifying assumptions that there are no barriers to gene flow, species are genetically homogeneous (i.e., no population-specific local adaptation), and all individuals share the same niche. Yet, these assumptions are violated for most broadly distributed species. Here, we incorporate genetic data from the widespread riparian tree species narrowleaf cottonwood (Populus angustifolia) to examine whether including intraspecific genetic variation can alter model performance and predictions of climate change impacts. We found that (1) P. angustifolia is differentiated into six genetic groups across its range from México to Canada and (2) different populations occupy distinct climate niches representing unique ecotypes. Comparing model discriminatory power, (3) all genetically informed ecological niche models (gENMs) outperformed the standard species-level ENM (3-14% increase in AUC; 1-23% increase in pROC). Furthermore, (4) gENMs predicted large differences among ecotypes in both the direction and magnitude of responses to climate change and (5) revealed evidence of niche divergence, particularly for the Eastern Rocky Mountain ecotype. (6) Models also predicted progressively increasing fragmentation and decreasing overlap between ecotypes. Contact zones are often hotspots of diversity that are critical for supporting species' capacity to respond to present and future climate change, thus predicted reductions in connectivity among ecotypes is of conservation concern. We further examined the generality of our findings by comparing our model developed for a higher elevation Rocky Mountain species with a related desert riparian cottonwood, P. fremontii. Together our results suggest that incorporating intraspecific genetic information can improve model performance by addressing this important source of variance. gENMs bring an evolutionary perspective to niche modeling and provide a truly "adaptive management" approach to support conservation genetic management of species facing global change.

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Our objective was to evaluate the effectiveness of protected areas (PAs) in the Paraná-Paraguay basin on multiple facets of ichthyofauna, both currently and in future climate change scenarios, based on reaching the 17% of conserved terrestrial and inland water defined by Aichi Target 11. Analyses were carried out vis-à-vis a distribution of 496 native species, modeling for the present and for the future, and in moderate and pessimistic scenarios of greenhouse gases. We calculated species richness, functional richness, and phylogenetic diversity, overlapping the combination of these facets with the PAs. The results indicate that the current PAs of the Paraná-Paraguay basin are not efficient in protecting the richest areas of ichthyofauna in their multiple facets. While there is a larger overlap between PAs and the richest areas in phylogenetic diversity, the values are too low (2.37%). Currently, the overlap between PAs and areas with larger species richness, functional richness, and phylogenetic diversity is only 1.48%. Although this value can increase for future projections, the values of the indices decrease substantially. The relevant aquatic environments, biological communities, and climate change should be considered as part of the systematic planning of PAs that take into consideration the terrestrial environments and their threats.(AU)

Nosso objetivo foi avaliar a efetividade das áreas protegidas da bacia Paraná-Paraguai sobre múltiplas facetas da ictiofauna, atualmente e em cenários futuros de mudanças climáticas baseado em alcançar 17% de áreas protegidas, de acordo com os objetivos de Aichi. Análises foram feitas a partir da distribuição de 496 espécies para o presente e futuro, em diferentes cenários climáticos. Foram calculadas a riqueza de espécies, a riqueza funcional e a diversidade filogenética, sobrepondo a combinação destas facetas com as áreas protegidas. Os resultados indicaram que as áreas protegidas da bacia Paraná-Paraguai não são eficientes em proteger as áreas mais ricas em ictiofauna considerando diversas facetas. A maior sobreposição se dá entre as áreas protegidas e as áreas mais ricas em diversidade filogenética, mas os valores são muito baixos (2,37%). A sobreposição entre as áreas protegidas e os 17% das áreas com maior riqueza de espécies, riqueza funcional e diversidade filogenética é de apenas 1,48%. Para o futuro as projeções indicaram que a sobreposição pode aumentar, mas os valores dos índices caem consideravelmente. Os ambientes aquáticos e as mudanças climáticas são componentes que devem ser considerados no planejamento sistemático de áreas protegidas que consideram essencialmente ambientes terrestres e suas ameaças.(AU)

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Our objective was to evaluate the effectiveness of protected areas (PAs) in the Paraná-Paraguay basin on multiple facets of ichthyofauna, both currently and in future climate change scenarios, based on reaching the 17% of conserved terrestrial and inland water defined by Aichi Target 11. Analyses were carried out vis-à-vis a distribution of 496 native species, modeling for the present and for the future, and in moderate and pessimistic scenarios of greenhouse gases. We calculated species richness, functional richness, and phylogenetic diversity, overlapping the combination of these facets with the PAs. The results indicate that the current PAs of the Paraná-Paraguay basin are not efficient in protecting the richest areas of ichthyofauna in their multiple facets. While there is a larger overlap between PAs and the richest areas in phylogenetic diversity, the values are too low (2.37%). Currently, the overlap between PAs and areas with larger species richness, functional richness, and phylogenetic diversity is only 1.48%. Although this value can increase for future projections, the values of the indices decrease substantially. The relevant aquatic environments, biological communities, and climate change should be considered as part of the systematic planning of PAs that take into consideration the terrestrial environments and their threats.(AU)

Nosso objetivo foi avaliar a efetividade das áreas protegidas da bacia Paraná-Paraguai sobre múltiplas facetas da ictiofauna, atualmente e em cenários futuros de mudanças climáticas baseado em alcançar 17% de áreas protegidas, de acordo com os objetivos de Aichi. Análises foram feitas a partir da distribuição de 496 espécies para o presente e futuro, em diferentes cenários climáticos. Foram calculadas a riqueza de espécies, a riqueza funcional e a diversidade filogenética, sobrepondo a combinação destas facetas com as áreas protegidas. Os resultados indicaram que as áreas protegidas da bacia Paraná-Paraguai não são eficientes em proteger as áreas mais ricas em ictiofauna considerando diversas facetas. A maior sobreposição se dá entre as áreas protegidas e as áreas mais ricas em diversidade filogenética, mas os valores são muito baixos (2,37%). A sobreposição entre as áreas protegidas e os 17% das áreas com maior riqueza de espécies, riqueza funcional e diversidade filogenética é de apenas 1,48%. Para o futuro as projeções indicaram que a sobreposição pode aumentar, mas os valores dos índices caem consideravelmente. Os ambientes aquáticos e as mudanças climáticas são componentes que devem ser considerados no planejamento sistemático de áreas protegidas que consideram essencialmente ambientes terrestres e suas ameaças.(AU)

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Nysius simulans (Stål) is a suctorial, fluid feeding herbivore that can transmit toxins and spread pathogens via saliva and is an economically important pest for soybean in South America. Currently, N. simulans in soybean is predominantly found in Argentina, but future changes in the distribution from both dispersal and range shifts due to climate change may affect soybean cultivation in southern South America. We developed a species distribution model to examine the distribution range of N. simulans. We compared the potential distribution of N. simulans under current and future projected climatic conditions in order to identify future areas of natural occurrence with ecological niche models using Maxent. Current records of N. simulans show that while the species is present in Argentina, and some areas of Brazil, Paraguay, Peru, and Uruguay, our models suggest that many new suitable areas will be available for N. simulans under climate change including other regions of Argentina, and southern Chile. Our results also predict potential future range shifts and distributions into Bolivia, but not Peru nor Brazil. In our model, seasonal trends in temperature were shown to have the greatest contribution to the potential distribution, whereas isothermality (i.e., temperature variability) was correlated to potential future distribution ranges. We conclude that current populations of N. simulans may be expanding its distribution range by diffusion (i.e., range expansion over generations at the margins of populations), and regions with potential future N. simulans distribution should be closely monitored.

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The number of reports of tick parasitism in amphibians and reptiles has increased over the past few years, including new host and location records for Amblyomma rotundatum and Amblyomma dissimile. However, knowledge of the geographical distribution remains incomplete, and in many regions of Brazil, the presence of these vectors has not been investigated. Several candidate models were built using a correlative maximum entropy approach, and best-fitting models were selected based on statistical significance, predictive ability, and complexity based on current climatic trends and future projected climate changes. Final models showed a good ability to discriminate A. rotundatum and A. dissimile current and future potential distributions. The entire country had higher predicted suitability for A. rotundatum while A. dissimile was mainly restricted to the Amazon and Pantanal biomes. A. rotundatum is a species with enormous potential for dissemination in the next decades, potentially through the legal and illegal transport of reptiles and amphibians. The proposed model is useful for targeting surveillance efforts increasing the efficiency and accuracy of future ecological research and tick management efforts.

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Host plant species have very specific interconnection with galling species. Here, we estimate the potential distribution of the host plant species Andira humilis Mart. ex Benth. (Fabaceae) to consequently locate the potential distribution ranges of its galling species Lopesia andirae Garcia, Lima, Calado, and Guimarães (2017) based on ecological requirements. The ecological niche model was built using Maxent v.3.4.1k, an algorithm that estimates species distributions. We found suitable habitats for L. andirae encompassing areas of the Cerrado, Caatinga and Atlantic Forest. Annual mean temperature (70.2%) and temperature annual range (13.9%) were the most critical factors shaping A. humilis and necessarily L. andirae. Our results can guide taxonomists and ecologists regarding the delineation of sampling areas as well as conservation strategies for this ecological interaction.(AU)

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Host plant species have very specific interconnection with galling species. Here, we estimate the potential distribution of the host plant species Andira humilis Mart. ex Benth. (Fabaceae) to consequently locate the potential distribution ranges of its galling species Lopesia andirae Garcia, Lima, Calado, and Guimarães (2017) based on ecological requirements. The ecological niche model was built using Maxent v.3.4.1k, an algorithm that estimates species’ distributions. We found suitable habitats for L. andirae encompassing areas of the Cerrado, Caatinga and Atlantic Forest. Annual mean temperature (70.2%) and temperature annual range (13.9%) were the most critical factors shaping A. humilis and necessarily L. andirae. Our results can guide taxonomists and ecologists regarding the delineation of sampling areas as well as conservation strategies for this ecological interaction.

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BACKGROUND: The water rat Nectomys squamipes (Cricetidae: Sigmodontinae) is a semiaquatic rodent from eastern South America that shows shallow genetic structure across space, according to some studies. We tested the influence of hydrography and climatic changes on the genetic and phylogeographic structure of this semiaquatic small mammal. METHODS: DNA sequences of two mitochondrial genetic markers (Cyt b and D-loop) and six microsatellite loci from water rats were collected at 50 localities in five river basins in the Atlantic Forest along the eastern coast of South America. We evaluated the genetic structure within and among river basins, and we estimated divergence dates. Species distribution models for the present and past were built to identify possible gene flow paths. RESULTS: Mitochondrial data and species distribution models showed coherent results. Microsatellite loci showed a more complex pattern of genetic differentiation. The diversification of N. squamipes haplotypes occurred during the Pleistocene and the river basin cannot explain most of the genetic structure. We found evidence of population expansion during the last glacial maximum, and gene flow paths indicate historical connections among rivers in the Atlantic Forest. DISCUSSION: Historical connections among rivers in the Atlantic Forest may have allowed N. squamipes to disperse farther across and within basins, leading to shallow genetic structure. Population expansions and gene flow through the emerged continental shelf during glacial period support the Atlantis forest hypothesis, thus challenging the forest refuge hypothesis.

RESUMO

Recent hypotheses to explain tropical diversity involves the Neogene and Quaternary geoclimatic dynamics, but the absence of unambiguous data permitting the choice between alternative hypotheses makes a general theory for the origin of tropical biodiversity far to be achieved. The occurrence of Chironius snakes in well-defined biogeographical regions led us to adopt Chironius as a model to unveil patterns of vertebrate diversification in the Neotropics. Here, we used molecular markers and records on geographic distribution to investigate Chironius evolution and, subsequently, providing hints on diversification in the Neotropics. To avoid analyzing nominal species that do not constitute exclusive evolutionary lineages, we firstly conducted a species delimitation study prior to carrying out the species distribution modeling analysis. We generated 161 sequences of 12S, 16S, c-mos and rag2 for 15 species and 50 specimens, and included additional data from GenBank yielding a matrix of 137 terminals, and performed the following evolutionary analyses: inference of a concatenated gene tree, estimation of gene divergence times, inference of the coalescent-based phylogeny of Chironius, estimation of effective population sizes and modeling potential distribution of species across the last millennia. We tested for species boundaries within Chironius by implementing a coalescent-based Bayesian species delimitation approach. Our analyses supported the monophyly of Chironius, although our findings underscored cryptic candidate species in C. flavolineatus and C. exoletus. The inferred timetree suggested that Chironius snakes have evolved in the early Miocene (ca. 20.2Mya) and began to diversify from the late Miocene to the early Pliocene, values that are much older than previously reported. Following genetic divergence of virtually all extant Chironius species investigated, the effective sizes of the populations have expanded when compared to their MRCAs. The evolutionary and SDM data from C. brazili and C. diamantina provided additional evidence of the origin of species in the Neotropics. We argue that temperature, instead of altitude, has been the major driving factor in the evolution of both species, and thus we present a case for the consequences of global warming.

Assuntos

RESUMO

Dinoflagellates of the genus Ceratium are predominantly found in marine environments, with a few species in inland waters. Over the last decades, the freshwater species Ceratium hirundinella and Ceratium furcoides have colonized and invaded several South American basins. The purpose of this study was to create a distribution model for the invasive dinoflagellate C. furcoides in South America in order to further investigate the basins at potential risk, as well as the environmental conditions that influence its expansion. This species is known to develop blooms due to its mobility, resistance to sedimentation, and optimized use of resources. Although nontoxic, blooms of the species cause many problems to both the natural ecosystems and water users. Potential distribution was predicted by using a maximum entropy algorithm (MaxEnt). Model was run with 101 occurrences obtained from the scientific literature, and climatic, hydrological and topographic variables. The developed model had a very good performance for the study area. The most susceptible areas identified were mainly concentrated in the basins between southeastern Brazil and northeastern Argentina. Besides already affected regions, new potentially suitable areas were identified in temperate regions of South America. The information generated here will be useful for authorities responsible for water and watershed management to monitor the spread of this species and address problems related to its establishment in new environments.

Assuntos