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ABSTRACT Influence of Quaternary climate change on the potencial distribution of Atlantic Forest dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae). The role of Cenozoic paleoclimatic changes in the distribution of dung beetles species from the Atlantic Forest (AF) remains poorly understood. We used ecological niche modeling under different scenarios (present, 6 ka, 21 ka, and 120 ka) to investigate how climatic oscillations during the Quaternary might have influenced the distribution of species endemic to this region. Models were built for five of the nine dung beetle species of the Dichotomius sericeus group: D. iannuzziae, D. irinus, D. laevicollis, D. schiffleri, and D. sericeus. The models of climatic suitability for D. irinus and D. laevicollis show a similar historical pattern in response to climate change but were divergent from D. iannuzziae, D. schiffleri, and D. sericeus. Dichotomius schiffleri is the species with the smallest area of ​​potencial occurrence. Over time, the species probably remained limited to lowland AF areas on the Brazilian coast and, it is currently found preferentially in Restinga ecosystems along the coast. Regarding the potential distribution models at the present, D. iannuzziae, D. schiffleri, and D. sericeus have potential distributions similar to their realized distribution. This study shows that the historical distribution of the D. sericeus species group has been influenced by paleoclimatic changes that occurred in the AF over the last 120 ka.

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The specimen previously identified as Marsupellamicrophylla from Brazil is reassessed and described as a new species, M.brasiliensis. The new species is characterized by paroicous inflorescence, bispiral elaters, scale-like, commonly unlobed leaves and very small leaf cells. Descriptions and drawings are provided along with a corresponding discussion of the morphological peculiarity of the new species. Marsupellabrasiliensis belongs to sect. Stolonicaulon, and the distribution of Marsupellasect.Stolonicaulon in the New World is confirmed. The infrageneric position of M.microphylla remains unresolved, and whether it belongs to the same section is still unclear.

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The development of coral reefs results from the interaction between ecological and geological processes in space and time. Their difference in scale, however, makes it difficult to detect the impact of ecological changes on geological reef development. The decline of coral cover over the last 50 years, for example, has dramatically impaired the function of ecological processes on reefs. Yet given the limited-resolution of their Holocene record, it is uncertain how this will impact accretion and structural integrity over longer timescales. In addition, reports of this ecological decline have focused on intrinsic parameters such as coral cover and colony size at the expense of extrinsic ones such as geomorphic and environmental variables. Despite these problems, several attempts have been made to predict the long-term accretion status of reefs based entirely on the contemporary health status of benthic communities. Here we explore how this ecological decline is represented within the reef geomorphic structure, which represents the long-term expression of reef development. Using a detailed geomorphic zonation scheme, we analyze the distribution and biodiversity of reef-building corals in fringing-reef systems of the Mesoamerican Reef tract. We find a depth-related pattern in community structure which shows that the relative species distribution between geomorphic zones is statistically different. Despite these differences, contemporary coral assemblages in all zones are dominated by the same group of pioneer generalist species. These findings imply that first, coral species distribution is still controlled by extrinsic processes that generate the geomorphic zonation; second, that coral biodiversity still reflects species zonation patterns reported by early studies; and third that dominance of pioneer species implies that modern coral assemblages are in a prolonged post-disturbance adjustment stage. In conclusion, any accurate assessment of the future viability of reefs requires a consideration of the geomorphic context or risks miscalculating the impact of ecological changes on long-term reef development.

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Many parasitoid species discriminate already parasitized hosts, thus avoiding larval competition. However, females incur in superparasitism under certain circumstances. Superparasitism is commonly observed in the artificial rearing of the parasitoid Diachasmimorpha longicaudata, yet host discrimination has been previously suggested in this species. Here, we addressed host discrimination in virgin D. longicaudata females in a comprehensive way by means of direct and indirect methods, using Ceratitis capitata and Anastrepha fraterculus which are major fruit fly pests in South America. Direct methods relied on the description of the foraging behaviour of females in arenas with parasitized and non-parasitized host larvae. In the indirect methods, healthy larvae were offered to single females and the egg distributions were compared to a random distribution. We found that D. longicaudata was able to recognize parasitized host from both host species, taking 24 h since a first parasitization for A. fraterculus and 48 h for C. capitata. Indirect methods showed females with different behaviours for both host species: complete discrimination, non-random (with superparasitism), and random distributions. A larger percentage of females reared and tested on A. fraterculus incurred in superparasitism, probably associated with higher fecundity. In sum, we found strong evidence of host discrimination in D. longicaudata, detecting behavioural variability associated with the host species, the time since the first parasitization and the fecundity of the females.

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Microbial communities within oxygen minimum zones (OMZs) are crucial drivers of marine biogeochemical cycles; however, we still lack an understanding of how these communities are distributed across an OMZ. We explored vertical (from 5 to 500 m depth) and horizontal (coast to open ocean) distribution of bacterioplankton and its relationships with the main oceanographic conditions in three transects of the tropical Mexican Pacific OMZ. The distribution of the microbial diversity and the main clades changed along the transition from oxygen-rich surface water to the OMZ core, demonstrating the sensitivity of key bacterial groups to deoxygenation. The euphotic zone was dominated by Synechococcales, followed by Flavobacteriales, Verrucomicrobiales, Rhodobacterales, SAR86, and Cellvibrionales, whereas the OMZ core was dominated by SAR11, followed by SAR406, SAR324, SAR202, UBA10353 marine group, Thiomicrospirales and Nitrospinales. The marked environmental gradients along the water column also supported a high potential for niche partitioning among OMZ microorganisms. Additionally, in the OMZ core, bacterial assemblages from the same water mass were more similar to each other than those from another water mass. There were also important differences between coastal and open-ocean communities: Flavobacteriales, Verrucomicrobiales, Rhodobacterales, SAR86, and Cellvibrionales were more abundant in coastal areas, while Synechococcales, SAR406, SAR324, SAR202, UBA10353 marine group, and Thiomicrospirales were more abundant in the open ocean. Our results suggest a biogeographic structure of the bacterioplankton in this OMZ region, with limited community mixing across water masses, except in upwelling events, and little dispersion of the community by currents in the euphotic zone.

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On this study, we used camera traps in a Semi deciduous Seasonal Forest, northeast of Brazil, to estimate the frequencies of occurrence of two Neotropical herbivorous mammals: the spotted paca (Cuniculus paca) and the tapeti (Sylvilagus brasiliensis), analyzing their seasonal variations of spatial distribution. We also characterized the activity pattern of the species and their seasonal variation. The herbivorous frequencies of occurrence were constant during all the seasons. In general, both species were mostly active at night. However, between the rainy and dry season, we identified differences in spotted paca activity peaks. Here we present one of the first studies on the tapeti, whose ecology is understudied. Our results also show a general view of the spotted paca and tapeti behavior strategies to seasonal variations. Due to the scarce food resource in the dry season, possibly these herbivorous need to search for different kinds of food available IFS around.(AU)

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On this study, we used camera traps in a Semi deciduous Seasonal Forest, northeast of Brazil, to estimate the frequencies of occurrence of two Neotropical herbivorous mammals: the spotted paca (Cuniculus paca) and the tapeti (Sylvilagus brasiliensis), analyzing their seasonal variations of spatial distribution. We also characterized the activity pattern of the species and their seasonal variation. The herbivorous frequencies of occurrence were constant during all the seasons. In general, both species were mostly active at night. However, between the rainy and dry season, we identified differences in spotted paca activity peaks. Here we present one of the first studies on the tapeti, whose ecology is understudied. Our results also show a general view of the spotted paca and tapeti behavior strategies to seasonal variations. Due to the scarce food resource in the dry season, possibly these herbivorous need to search for different kinds of food available IFS around.

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Populations of the marine benthic red macroalgae Hypnea musciformis and Hypnea pseudomusciformis along the Atlantic and Pacific Oceans were tested for phylogeographic structure using the DNA barcode COI-5P combined with rbcL for the construction of the phylogenetic tree. Strong patterns of genetic structure were detected across 210 COI-5P DNA sequences, and 37 COI-5P haplotypes were found, using multiple statistical approaches. Hypnea musciformis was found in the Northeast and Northwest Atlantic, the Mediterrean Sea, Namibia, and along the Pacific coast of Mexico. Two new putative species were detected, Hypnea sp. 1 in the Caribbean Sea and Hypnea sp. 2 in the Dominican Republic. Three distinct marine phylogeographic provinces were recognized in the Southern Hemisphere for H. pseudomusciformis: Uruguay, South-Southeast Brazil, and Northeast Brazil. The degree of genetic isolation and distinctness among these provinces varied considerably. The Uruguay province was the most genetically distinct, as characterized by four unique haplotypes not shared with any of the Brazilian populations. Statistically significant results support both, isolation by distance and isolation by environment hypotheses, explaining the formation and mantainance of phylogeographic structuring along the Uruguay-Brazil coast. Geographic, taxonomic and molecular marker concordances were found between our H. pseudomusciformis results and published studies. Furthermore, our data indicate that the Hawaiian introduced populations of H. musciformis contain Hypnea sp. 1 haplotypes, the current known distribution of which is restricted to the Caribbean.

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Accurate and detailed species distribution maps are fundamental for documenting and interpreting biological diversity. For snakes, an ecologically diverse group of reptiles, syntheses and detailed data on distribution patterns remain scarce. We present the first comprehensive collection of detailed, voucher-based, point-locality, range maps for all described and documented Brazilian snakes, with the major aim of mitigating the Wallacean shortfall and as a contribution towards a better understanding of this rich, threatened, and poorly studied megadiverse fauna. We recorded a total of 412 snake species in Brazil on the basis of an extensive and verified point-locality database of 163,498 entries and 75,681 unique records (available here as Online Supporting Information). Our results reveal previously undocumented patterns of distribution, sampling effort, richness, and endemism levels, resulting in a more objective view of snake diversity in the Neotropics. Apart from these achievements, we understand that the most relevant and enduring contribution of the present atlas is to stimulate researchers to publish corrections, additions, and new discoveries.

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Two new species of the genus Ateuchus Weber are described from the region of Los Chimalapas, Oaxaca, Mexico: A. benitojuarezisp. n. and A. colossussp. n. A diagnosis for distinguishing these new species from the other species of this genus in North America is included. This paper is illustrated with pictures of the dorsal habitus and the male genitalia of the new species. The evolutionary relationships of the species are discussed, as well as their distribution and ecology. It is considered that the species of the genus Ateuchus present in North and Central America correspond to the Typical Neotropical and Mountain Mesoamerican distribution patterns.

ResumenDescribimos dos especies nuevas del género Ateuchus Weber, de la región de Los Chimalapas, Oaxaca, México: A. benitojuarezisp. n. y A. colossussp. n. Incluimos diagnosis para distinguir a estas especies nuevas del resto de especies del género presentes en Norteamérica. Presentamos ilustraciones del hábito dorsal y la genitalia masculina de las nuevas especies. Discutimos las relaciones evolutivas de las especies, así como también su distribución y ecología. Consideramos que las especies del género Ateuchus corresponden con los patrones de distribución Neotropical Típico y Mesoamericano de Montaña.

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Insect diversity patterns of high mountain ecosystems remain poorly studied in the tropics. Sampling dung beetles of the subfamilies Aphodiinae, Scarabaeinae, and Geotrupinae was carried out at four volcanoes in the Trans-Mexican Volcanic Belt (TMVB) in the Mexican transition zone at 2,700 and 3,400 MASL, and on the windward and leeward sides. Sampling units represented a forest-shrubland-pasture (FSP) mosaic typical of this mountain region. A total of 3,430 individuals of 29 dung beetle species were collected. Diversity, abundance and compositional similarity (CS) displayed a high variability at all scales; elevation, cardinal direction, or FSP mosaics did not show any patterns of higher or lower values of those measures. The four mountains were different regarding dispersion patterns and taxonomic groups, both for species and individuals. Onthophagus chevrolati dominated all four mountains with an overall relative abundance of 63%. CS was not related to distance among mountains, but when O. chevrolati was excluded from the analysis, CS values based on species abundance decreased with increasing distance. Speciation, dispersion, and environmental instability are suggested as the main drivers of high mountain diversity patterns, acting together at different spatial and temporal scales. Three species new to science were collected (>10% of all species sampled). These discoveries may indicate that speciation rate is high among these volcanoes-a hypothesis that is also supported by the elevated number of collected species with a restricted montane distribution. Dispersion is an important factor in driving species composition, although naturally limited between high mountains; horizontal colonization events at different time scales may best explain the observed species composition in the TMVB, complemented by vertical colonization events to a lesser extent. Environmental instability may be the main factor causing the high variability of diversity and abundance patterns found during sampling. Together, we interpret these results as indicating that species richness and composition in the high mountains of the TMVB may be driven by biogeographical history while variability in diversity is determined by ecological factors. We argue that current conservation strategies do not focus sufficiently on protecting high mountain fauna, and that there is a need for developing and applying new conservation concepts that take into account the high spatial and temporal variability of this system.

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Resumen:Los estudios sobre gradientes altitudinales han permitido examinar cambios en la riqueza y composición de los ensamblajes de aves, lo que hace posible obtener información sobre las variables ambientales que determinan su distribución y factores que definen la estructura. En este trabajo se describe la variación en la riqueza y composición de los ensamblajes de aves a través de un gradiente altitudinal al sur de Nayarit. Para analizar el comportamiento de la riqueza en el gradiente se obtuvo información mediante puntos de conteo en nueve intervalos altitudinales (separados cada 300 m de altitud) desde el nivel del mar hasta los 2 700 msnm. Se estandarizó el esfuerzo de muestreo y se realizaron curvas de rarefacción, y los cambios en la composición de especies se analizaron mediante análisis de clasificación jerárquica utilizando la técnica TWINSPAN. Para identificar las variables asociadas con los cambios en riqueza se analizó el efecto de la precipitación y de la estructura del hábitat mediante árboles de regresión. Para determinar si los cambios en composición responden a cambios en los tipos de vegetación se realizó un análisis de escalamiento multidimensional no métrico (NMDS). La riqueza de especies varió de forma significativa a través del gradiente: fue alta en las partes bajas del gradiente, alcanzó su valor máximo en la parte media y disminuyó monotónicamente con la elevación. Las especies respondieron a cambios en el gradiente y se agruparon en tres pisos altitudinales. Los análisis sugieren que los cambios en la riqueza y composición de las especies están influenciados por la vegetación, su estructura y precipitación, así como por diversos aspectos relacionados con características del hábitat y la perturbación. Estos aspectos deberán ser tomados en cuenta con el fin de diseñar estrategias adecuadas para la conservación de las aves de Nayarit.

Abstract:Elevation gradient studies have strengthened the evaluation of changes in richness and composition of bird assemblages. They also provide information on environmental variables that determine bird distribution, and the variables that define their population structure. Our aim was to describe their variation through an elevational cline in Southern Nayarit, Mexico. To analyze the behavior of richness across the gradient, we gathered information through point counts in nine elevational intervals (300 m from each other) from sea level to 2 700 m of elevation. With a standardized sampling effort, we produced rarefaction curves and analyzed changes in species composition by hierarchical classification using the TWINSPAN technique. In order to identify variables associated with richness changes, we examined the effect of precipitation and habitat structure via regression trees. An analysis of nonmetric multidimensional scaling (NMDS) was implemented with the purpose to determine if the changes in composition correspond to changes in vegetation types. Species richness varied significantly across the gradient: high in the lower parts of the gradient, reached its peak in the middle, and decreased monotonically with elevation. Species responded to changes in the cline and were grouped in three elevational zones. Analyses suggest that changes in richness and species composition are influenced by vegetation, its structure and precipitation regime, as well as various aspects related to habitat features and disturbance. These aspects should be taken into account in order to design appropriate strategies for the conservation of the birds of Nayarit. Rev. Biol. Trop. 64 (4): 1537-1551. Epub 2016 December 01.

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Abstract Here we examine assemblage structure of coprophagous Scarabaeidae (dung beetles) in the Pantanal of the state of Mato Grosso with respect to flooding regimes, soil texture, leaf litter volume and tree dominance in native and exotic pastures. Samples were collected along 30 transects of 250 m in length in a 5×5 km grid (25 km2). Five pitfalls baited with human feces were placed in each transect. A total of 1692 individuals in 19 species were captured, the majority in the subfamily Scarabaeinae and Aphodiinae. Assemblages were influenced by the duration of flooding and leaf litter volume. None of the other habitat variables was correlated with species richness. Cultivated pastures with exotic grasses were unimportant for composition of the assemblages of beetles. These results indicate that duration of flooding is the most important regulating force in this community.

Resumo Esse estudo avaliou a estrutura espacial de assembleias de Scarabaeidae coprófagos no Pantanal de Mato Grosso, em função do tempo de inundação, textura do solo, volume da serapilheira, dominância de arbóreas, pastagens nativa e exótica. As coletas foram realizadas em 30 transectos de 250 m cada distribuídos sistematicamente em uma área de 25 km2. Cinco armadilhas pitfall iscadas com fezes humanas foram instaladas em cada transecto, e obtidos 1.692 indivíduos distribuídos em 19 espécies pertencentes às subfamílias Scarabaeinae e Aphodiinae. A estrutura e composição das assembleias foram afetadas pelo tempo de inundação e o volume da serapilheira. Todas as variáveis explanatórias foram fracamente correlacionadas e de forma não significativa com a riqueza de espécies. A existência de pastagem exótica não afetou a composição das assembleias de besouros. Esses resultados indicam que o tempo de inundação é a principal força reguladora dessa comunidade no ambiente pantaneiro.

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Abstract Here we examine assemblage structure of coprophagous Scarabaeidae (dung beetles) in the Pantanal of the state of Mato Grosso with respect to flooding regimes, soil texture, leaf litter volume and tree dominance in native and exotic pastures. Samples were collected along 30 transects of 250 m in length in a 5×5 km grid (25 km2). Five pitfalls baited with human feces were placed in each transect. A total of 1692 individuals in 19 species were captured, the majority in the subfamily Scarabaeinae and Aphodiinae. Assemblages were influenced by the duration of flooding and leaf litter volume. None of the other habitat variables was correlated with species richness. Cultivated pastures with exotic grasses were unimportant for composition of the assemblages of beetles. These results indicate that duration of flooding is the most important regulating force in this community.

Resumo Esse estudo avaliou a estrutura espacial de assembleias de Scarabaeidae coprófagos no Pantanal de Mato Grosso, em função do tempo de inundação, textura do solo, volume da serapilheira, dominância de arbóreas, pastagens nativa e exótica. As coletas foram realizadas em 30 transectos de 250 m cada distribuídos sistematicamente em uma área de 25 km2. Cinco armadilhas pitfall iscadas com fezes humanas foram instaladas em cada transecto, e obtidos 1.692 indivíduos distribuídos em 19 espécies pertencentes às subfamílias Scarabaeinae e Aphodiinae. A estrutura e composição das assembleias foram afetadas pelo tempo de inundação e o volume da serapilheira. Todas as variáveis explanatórias foram fracamente correlacionadas e de forma não significativa com a riqueza de espécies. A existência de pastagem exótica não afetou a composição das assembleias de besouros. Esses resultados indicam que o tempo de inundação é a principal força reguladora dessa comunidade no ambiente pantaneiro.

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Here we examine assemblage structure of coprophagous Scarabaeidae (dung beetles) in the Pantanal of the state of Mato Grosso with respect to flooding regimes, soil texture, leaf litter volume and tree dominance in native and exotic pastures. Samples were collected along 30 transects of 250 m in length in a 5×5 km grid (25 km2). Five pitfalls baited with human feces were placed in each transect. A total of 1692 individuals in 19 species were captured, the majority in the subfamily Scarabaeinae and Aphodiinae. Assemblages were influenced by the duration of flooding and leaf litter volume. None of the other habitat variables was correlated with species richness. Cultivated pastures with exotic grasses were unimportant for composition of the assemblages of beetles. These results indicate that duration of flooding is the most important regulating force in this community.(AU)

Esse estudo avaliou a estrutura espacial de assembleias de Scarabaeidae coprófagos no Pantanal de Mato Grosso, em função do tempo de inundação, textura do solo, volume da serapilheira, dominância de arbóreas, pastagens nativa e exótica. As coletas foram realizadas em 30 transectos de 250 m cada distribuídos sistematicamente em uma área de 25 km2. Cinco armadilhas pitfall iscadas com fezes humanas foram instaladas em cada transecto, e obtidos 1.692 indivíduos distribuídos em 19 espécies pertencentes às subfamílias Scarabaeinae e Aphodiinae. A estrutura e composição das assembleias foram afetadas pelo tempo de inundação e o volume da serapilheira. Todas as variáveis explanatórias foram fracamente correlacionadas e de forma não significativa com a riqueza de espécies. A existência de pastagem exótica não afetou a composição das assembleias de besouros. Esses resultados indicam que o tempo de inundação é a principal força reguladora dessa comunidade no ambiente pantaneiro.(AU)

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In this study we present an ecological pattern of elevation and temporal variations found in the Chrysomelidae in one of the highest mountains in southeastern Brazil. Monthly surveys using an entomological sweep-net were conducted between April 2011 and June 2012, at five different elevations (800 m, 1000 m, 1750 m, 2200 m and 2450 m). A total of 2318 individuals were collected, belonging to 91 species. The elevation and temporal patterns of distribution of Chrysomelidae were heavily dominated by the Galerucinae. This subfamily had the highest richness and abundance at intermediate altitudes and during the rainy season. Probably the food availability as well as abiotic factors this time of the year favor the development of Galerucinae. Also, most of the more abundant Galerucinae species showed broad elevation ranges but approximately 20% of these species were only collected on the mountaintop sites. We would expect these species to be ones most prone to extinction in a scenario of climate warming or even after local disturbances.

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Las enfermedades tropicales son infecciones provocadaspor mosquitos y moscas que transmiten parßsitos, bacteriaso virus a individuos, una de ellas es el dengue, el cual atacaespecialmente a personas en condiciones de pobreza ymarginalidad, proliferando en lugares con saneamiento bßsicodeficiente, lo cual ha aumentado significativamente el númerode casos. Objetivo: en el presente artÝculo se usan los Sistemasde Informaci¾n Geogrßfica (SIG) para el modelamiento depatrones de distribuci¾n espacial de enfermedades tropicales.Se toma como caso de estudio los reportes del dengue mes ames de los a±os 2008, 2009 y 2011 en el Valle de Aburrß en lajurisdicci¾n de MedellÝn, Colombia. MetodologÝa: se ubicaronespacialmente los casos de dengue notificados a la SecretarÝa deSalud de MedellÝn a travÚs de las direcciones de las viviendasde los pacientes. Se ubicaron geoespacialmente utilizando elsoftware ArcGis 10, y las herramientas de anßlisis espacial IDWy Slope para demostrar que el fen¾meno del dengue cumplecon el principio de autocorrelaci¾n espacial. Resultados ydiscusi¾n: la enfermedad muestra patrones espaciales en elsector suroccidental de MedellÝn; Corregimiento de Altavistay en las Comunas de BelÚn y Guayabal; sin embargo, serÝa degran interÚs estudiar este fen¾meno con variables ambientalesy poder tener mßs herramientas para la toma de decisiones enlas actividades de prevenciónn del dengue...

Tropical diseases are infections caused by mosquitoes and flieswhich transmit parasites, bacteria or viruses of people. One ofthese diseases is dengue, which particularly attacks those livingin poor or marginalized conditions, proliferating in placeslacking basic sanitation, which has significantly increased thenumber of cases. Objective: Geographic Information Systems(gis) were used in this paper for the purpose of modeling thespatial distribution patterns of tropical diseases. Monthlyreports on dengue from the years 2008, 2009 and 2011 in theAburrß valley, under the jurisdiction of MedellÝn, Colombia,were taken as a case study. Methodology: Dengue cases ofwhich the MedellÝn Health Secretary was notified were spatiallylocated using the addresses of the patients' homes. ArcGis 10software was used to geo-spatially locate the cases, while IDWand Slope spatial analysis tools were employed to demonstratethat the dengue phenomenon complies with the principle ofspatial auto-correlation. Results and discussion: The diseaseshows spatial patterns in the south-west sector of MedellÝn; theAltavista township and the BelÚn and Guayabal municipalities,and it would be of great interest to study this phenomenon withenvironmental variables and to have more tools available fordecision-making in activities for preventing dengue...

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What is the importance of open habitat in a predominantly closed forest to the dung beetle assemblage? The Atlantic Forest in Brazil is one of the most highly disturbed ecosystems and is mainly represented by fragmented areas. However, in places where human disturbances have ceased, certain areas are showing a natural regeneration pattern. The aim of the present study was to determine how the dung beetle assemblage responds to distinct habitat structures in a fragment of Atlantic Forest. For such, open and closed forest areas were sampled in a fragment of the Atlantic Forest in the northeastern region of Brazil. Pitfall traps baited with excrement and carrion were used to collect the beetles. A total of 7,267 individuals belonging to 35 species were captured. Canthon chalybaeus and C. mutabilis were restricted to open areas. Nearly 90% of the individuals of C. aff. simulans and Deltochilum aff. irroratum were identified in these areas. A higher percentage (> 50%) of Canthon staigi, Dichotomius aff. depressicolis and D. aff. sericeus occurred in closed areas. Abundance differed between areas, with higher values in closed areas. Richness was not influenced by the habitat structure. NMDS ordination exhibited the segregation of areas and ANOSIM confirmed that this variable explained the assemblage of dung beetle species. The findings of the present study validate that open areas are associated to more restrictive conditions, limiting a higher abundance of dung beetle. Although situated near preserved fragments, the studied open areas increase the heterogeneity of the general landscape.

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The tree species composition of seasonally dry tropical forests (SDTF) in north-eastern and central Brazil is analyzed to address the following hypotheses: (1) variations in species composition are related to both environment (climate and substrate) and spatial proximity; (2) SDTF floristic units may be recognized based on peculiar composition and environment; and (3) the Arboreal Caatinga, a deciduous forest occurring along the hinterland borders of the Caatinga Domain, is one of these units and its flora is more strongly related to the caatinga vegetation than to outlying forests. The study region is framed by the Brazilian coastline, 50th meridian west and 21st parallel south, including the Caatinga Domain and extensions into the Atlantic Forest and Cerrado Domains. Multivariate and geostatistic analyses were performed on a database containing 16,226 occurrence records of 1332 tree species in 187 georeferenced SDTF areas and respective environmental variables. Tree species composition varied significantly with both environmental variables and spatial proximity. Eight SDTF floristic units were recognized in the region, including the Arboreal Caatinga. In terms of species composition, its tree flora showed a stronger link with that of the Cerrado Dry Forest Enclaves. On the other hand, in terms of species frequency across sample areas, the links were stronger with two other units: Rock Outcrops Caatinga and Agreste and Brejo Dry Forests. There is a role for niche-based control of tree species composition across the SDTFs of the region determined primarily by the availability of ground water across time and secondarily by the amount of soil mineral nutrients. Spatial proximity also contributes significantly to the floristic cohesion of SDTF units suggesting a highly dispersal-limited tree flora. These units should be given the status of eco-regions to help driving the conservation policy regarding the protection of their biodiversity.

RESUMO

Na floresta Ombrófila Densa do Parque Estadual de Carlos Botelho - PECB (ca. 37.000 ha) foi avaliada a composição, riqueza e distribuição geográfica das espécies vasculares nativas. A análise de 1143 espécies pertencentes a 140 famílias (sensu APG III) confirmaram o padrão encontrado para outras florestas do Leste do Brasil, com altas riquezas de Myrtaceae (85 espécies), Orchidaceae (81), Fabaceae (57), Asteraceae, Melastomataceae (54), Lauraceae (53), Rubiaceae (51), Bromeliaceae (43), Piperaceae (30) e Solanaceae (25), além de pteridófitas (123). Os gêneros mais ricos do Parque foram: Eugenia (34), Ocotea (26), Leandra, Myrcia, Vriesea (18), Piper (16), Solanum (15), Miconia (14), Mollinedia (13) e Peperomia (12). Houve grande variação na riqueza e composição de espécies entre hábitos, bem como no número de famílias representadas nos hábitos considerados (apenas Rubiaceae teve espécies em todos os hábitos, exceto parasitas). As árvores obtiveram a maior contribuição na riqueza total (39,1%), valor que representou mais de 20% das espécies de árvores citadas para toda a Floresta Atlântica do Sudeste do Brasil. Em seguida, foram os epífitos (22,4%), ervas (18,4%), arbustos (10,1%), lianas (9,1%) e parasitas (0,9%). De maneira geral, a riqueza e a composição por hábitos foram bastante similares ao encontrado nas demais florestas neotropicais (e.g. alta contribuição de pteridófitas ente os epífitos), apesar de alguns dos hábitos permanecerem subamostrados no PECB (principalmente ervas, lianas e epífitos). A ocorrência de espécies endêmicas da Floresta Atlântica foi elevada (65%), com predominância de espécies de ocorrência no Sul da Floresta Atlântica (43%). Espécies pantropicais foram raras (2%), sendo mais comuns entre as pteridófitas e entre as herbáceas. Myrtaceae e Melastomataceae foram as famílias com maior número e proporção de espécies endêmicas.

In the Montane and Submontane Rain Forest of the Carlos Botelho State Park - PECB (ca. 37,000 ha) the composition, richness and geographical distribution of native, vascular forest species was evaluated. The analysis of 1143 species of 140 families supported the pattern found for other forests of Eastern Brazil, showing high species richness of Myrtaceae (85 species), Orchidaceae (81), Fabaceae (57), Asteraceae, Melastomataceae (54), Lauraceae (53), Rubiaceae (51), Bromeliaceae (43), Piperaceae (30) and Solanaceae (25), besides ferns (123). The most species-rich genera were Eugenia (34), Ocotea (26), Leandra, Myrcia, Vriesea (18), Piper, Solanum (16), Miconia (14), Mollinedia (13), and Peperomia (12). The richness and composition varied greatly among life forms, as well as the number of families represented in each one of them (only Rubiaceae had species in all life forms, except parasites). Trees had the largest contribution of total richness (39.1%), a value that represented more than 20% of the species listed for the whole Atlantic Forest of Southeastern Brazil. Trees were followed by epiphytes (22.4%), herbs (18.4%), shrubs (10.1%), lianas (9.1%), and parasites (0.9%). The overall richness and composition of life forms was quite close to other neotropical forests (e.g. high contribution of ferns among epiphytes), although some life forms remain undersampled in the PECB (mainly herbs, lianas and epiphytes). The occurrence of species endemic to the Atlantic Forest was pronounced (65%), with a predominance of species restricted to the Southern Atlantic Forest (43%). Pantropical species were rare (2%), being more common among ferns. Myrtaceae and Melastomataceae were the families with greater number and proportion of endemic species.