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Odonata species live through their immature development in aquatic habitats, where the eggs are adapted to survive the initial stages. The survival of the eggs is linked to the layers that make up the eggshell. These layers are common to all odonate species, but show variations among them, depending on the oviposition method. For example, endophytic eggs (laid in plant tissues) and exophytic eggs (laid on the water surface) have different morphologies, which may reveal egg adaptations to environmental conditions and stresses. The differences in the egg morphologies could be shown in the length of the egg layers, their histochemical composition, and in the ultrastructure. The histochemical composition can reveal several features that could lead us to a better understanding of its function, for example, how glycoproteins and total proteins could regulate the humidity and water retention in the eggs according to the environments in which the eggs are placed.

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Knowledge of the feeding habits of primate species is important for an understanding of their natural history and ecological interactions between their groups, and their interactions with their environments. Capuchin monkeys (Sapajus spp.) present significant diet flexibility and are a good model for investigating diet diversity between species. We undertook a systematic literature review of publications on the diet of free-living Sapajus spp. groups by using the Web of Science platform. We performed scientometric analyses of the objectives and hypotheses of the reviewed works, identified knowledge gaps, and evaluated the composition of each group's diet. Our results indicate geographic and taxonomic biases among the 59 published studies that we examined. The studies were focused on Sapajus nigritus, Sapajus libidinosus, and Sapajus apella, and undertaken in long-term study sites. Foraging and behavioral aspects of how food is processed were recurring themes. Capuchin monkeys increase their consumption of anthropogenic food according to its supply. Despite the similar objectives of these studies, standardized data collection protocols were not employed. Although Sapajus spp. are widely distributed and are used for cognitive studies, basic aspects of their natural history, such as their diet, remain unknown. We emphasize the importance of undertaking studies on this genus to fill the identified knowledge gaps, and propose that investigations should be carried out on the effects of dietary changes on individuals and groups. We stress that, as the Neotropical region is one of those most affected by anthropogenic impacts, opportunities to study these primates in their natural environments are diminishing daily.

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Agricultural expansion as a main human activity has affected pollinator's habitat, causing spatial distribution changes. Meanwhile, pollinators still provide pollination service to improve crop production. However, their spatial response is unclear because of environmental changes. This study sought to estimate spatial distribution of crop production and pollinator's richness, which can provide insights as to how they interact with the environment. We acquired environmental variables from remote sensing images and used a stacked species distribution model to predict selected bee species richness and a crop simulation model to simulate and calculate soybean production at a regional scale in the Cerrado for the period 2000-2015. Then, we analyzed their potential relationship. The results showed that higher selected bee species richness and higher soybean production occurred in the southern Cerrado. From 2000/08 to 2008/15 period, the selected bee species richness significantly decreased in the western part of the state of Bahia, the state of Goiás, and the northern region of the state of Minas Gerais; while soybean production increased in the states of Mato Grosso, Goiás, Bahia, and Tocantins. Correlation results of selected bee species richness and soybean production showed that they do not follow a linear relationship during the study period. Our findings indicate that the modeling method we proposed is robust to estimate spatial distribution of bee species richness and soybean production in the Cerrado at the regional scale and that the environment has a stronger influence on selected bee species richness than on soybean production. Moreover, climate effects and agricultural expansion are the main factors that affect their spatial distribution and interaction. Finally, our methodology provides a novel spatial perspective to analyze the relationship between pollinator and agricultural expansion corresponding with the environment, but future work is needed to collect a more comprehensive data set to improve model results.

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Ecological niche modeling (ENM) is a broadly used tool in different fields of plant ecology. Despite the importance of edaphic conditions in determining the niche of terrestrial plant species, edaphic data have rarely been included in ENMs of plant species perhaps because such data are not available for many regions. Recently, edaphic data has been made available at a global scale allowing its potential inclusion and evaluation on ENM performance for plant species. Here, we take advantage of such data and address the following main questions: What is the influence of distinct predictor variables (e.g. climatic vs edaphic) on different ENM algorithms? and what is the relationship between the performance of different predictors and geographic characteristics of species? We used 125 plant species distributed over the Neotropical region to explore the effect on ENMs of using edaphic data available from the SoilGrids database and its combination with climatic data from the CHELSA database. In addition, we related these different predictor variables to geographic characteristics of the target species and different ENM algorithms. The use of different predictors (climatic, edaphic, and both) significantly affected model performance and spatial complexity of the predictions. We showed that the use of global edaphic plus climatic variables generates ENMs with similar or better accuracy compared to those constructed only with climate variables. Moreover, the performance of models considering these different predictors, separately or jointly, was related to geographic properties of species records, such as number and distribution range. The large geographic extent, the variability of environments and the different species' geographical characteristics considered here allowed us to demonstrate that global edaphic data adds useful information for plant ENMs. This is particularly valuable for studies of species that are distributed in regions where more detailed information on soil properties is poor or does not even exist.

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The potential mutagenic and genotoxic effects of the herbicide atrazine were investigated in different developmental stages of Dendropsophus minutus tadpoles. These animals were exposed to 4 nominal concentrations of atrazine (2.25, 4.5, 9, and 18 mg/L) and 40 mg/L of Cyclophosphamide as a positive control, for 96 h. Negative controls were also added to the experiment. The tadpoles were divided into three groups according to Gosner's developmental stages, namely GS 25-33 as premetamorphic, GS 36-39 as prometamorphic, and GS 42-43 as metamorphic climax. Our results showed that the premetamorphic and metamorphic stages were more sensitive than the prometamorphic stage to the herbicide. A comet assay and micronucleus test for the sensitive stages demonstrated DNA damage in a concentration-dependent curve. Although a dose-response effect was not observed for the prometamorphic stage, a statistically significant difference was found between the treatment of 18 mg/L and the negative control. Moreover, the highest concentration of atrazine showed both the largest amount of DNA damage and the highest micronucleus frequency regardless of the developmental stage of D. minutus. In conclusion, atrazine was genotoxic and mutagenic for D. minutus in a dose-sensitive manner, dependent on larval developmental stages. Considering the prometamorphic stages showed no dose-response effect to atrazine, we suggest caution when using this stage in biomonitoring studies in order to avoid false negative results. Amphibians have been proven to be useful bioindicators, and we suggest replicating biomonitoring studies using different species to represent ecosystems' environmental impacts.

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Community assembly theory is founded on the premise that the relative importance of local environmental processes and dispersal shapes the compositional structure of metacommunities. The species sorting model predicts that assemblages are dominated by the environmental filtering of species that are readily able to disperse to suitable sites. We propose an ecophysiological hypothesis (EH) for the mechanism underlying the organization of species-sorting odonate metacommunities based on the interplay of thermoregulation, body size and the degree of sunlight availability in small-to-medium tropical streams. Due to thermoregulatory restrictions, the EH predicts (i) that larger species are disfavored in small streams and (ii) that streams exhibit a nested compositional pattern characterized by species' size distribution. To test the EH, we evaluate the longitudinal distribution of adult Odonata at 19 sites in 1st- to 6th-order streams in the Tropical Cerrado of Brazil. With increasing channel width, the total abundance and species richness of Anisoptera increased, while the abundance of Zygoptera decreased. The first axis of an ordination analysis of the species abundance data was directly related to channel width. Mean and maximum thorax size are positively correlated to channel width, but no relationship was found for the minimum thorax size, suggesting that there is no lower size constraint on the occurrence of these species. Additionally, a nested compositional pattern related to body size was observed. Our results support the EH and its use as an ecological assembly rule based on abiotic factors. Forest cover functions as a filter to determine which species successfully colonize a given site within a metacommunity. As a consequence, the EH also indicates higher treats for small-bodied zygopterans in relation to the loss of riparian forests in tropical streams.

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Brazilian sac brood is one of the worst diseases of Apis mellifera L. mainly in southeast Brazil. This disease affects the larval development after having been fed with "barbatimão" pollen (Stryphnodendron polyphyllum and Stryphnodendron adstringens); the workers become intoxicated and die between the prepupae and pupae stages. This study verified the effect of pollen substitute on the reduction of Apis mellifera L. mortality, caused by Brazilian sac brood during Stryphnodendron adstringens flowering. Two treatments were used: in treatment one, colonies received pollen substitute weekly (a blend of a soy flour, maize flour and wheat flour of equal proportions). The hives of treatment 2 didn´t receive the replacement of pollen substitute, receiving only the pollen found in nature. The hives which were fed with the pollen substitute had significant difference of 93.5% of brood survival viability when compared to non-fed which had 80.4% of survival. The frequency of pollen S. adstringens in pollen traps, in treatment 1, was of 0.21. However, in treatment 2, the frequency was of 4.38, indicating that the hives that were not fed with the substitute showed a higher frequency of pollen of this plant when compared with those who had the artificial diet. The results suggest that supplying with pollen substitute, before and during Stryphnodendron adstringens flowering, is important in reducing the effects of Brazilian sac brood disease.

A cria ensacada brasileira é uma das piores enfermidades de abelhas Apis mellifera L. africanizadas, principalmente do Sudeste do Brasil. Ela afeta o desenvolvimento das larvas, após serem alimentadas pelas abelhas nutrizes com o pólen do barbatimão (Stryphnodendron polyphyllum e Stryphnodendron adstringens), ocasionando a morte entre os estágios de pré-pupa e pupa. O objetivo deste trabalho foi verificar o efeito do substituto de pólen na redução da mortalidade da cria ensacada brasileira durante o florescimento do Stryphnodendron adstringens. Foram utilizados dois tratamentos: as colmeias do tratamento 1 receberam semanalmente substituto de pólen (mistura de farinha de soja, fubá e farinha de trigo em proporções iguais). As colmeias do tratamento 2 não receberam o substituto de pólen, tendo como único alimento o pólen que encontravam na natureza. As colmeias alimentadas apresentaram diferença significativa de 93,5% de viabilidade de sobrevivência de cria em relação às não alimentadas, que apresentaram 80,4% de sobrevivência. A frequência de pólen S. adstringens nos coletores de pólen, no tratamento 1, foi 0,21. Entretanto, no Tratamento 2, foi de 4,38, indicando que as colmeias que não se alimentaram com o substituto apresentaram maior frequência do pólen dessa planta, quando comparadas com as que dispunham da dieta artificial. Esse manejo sugere que a oferta do substituto de pólen, antes e durante a florada do Stryphnodendron adstringens, é importante na redução dos efeitos da cria ensacada brasileira em enxames de abelhas africanizadas.

RESUMO

Brazilian sac brood is one of the worst diseases of Apis mellifera L. mainly in southeast Brazil. This disease affects the larval development after having been fed with "barbatimão" pollen (Stryphnodendron polyphyllum and Stryphnodendron adstringens); the workers become intoxicated and die between the prepupae and pupae stages. This study verified the effect of pollen substitute on the reduction of Apis mellifera L. mortality, caused by Brazilian sac brood during Stryphnodendron adstringens flowering. Two treatments were used: in treatment one, colonies received pollen substitute weekly (a blend of a soy flour, maize flour and wheat flour of equal proportions). The hives of treatment 2 didn´t receive the replacement of pollen substitute, receiving only the pollen found in nature. The hives which were fed with the pollen substitute had significant difference of 93.5% of brood survival viability when compared to non-fed which had 80.4% of survival. The frequency of pollen S. adstringens in pollen traps, in treatment 1, was of 0.21. However, in treatment 2, the frequency was of 4.38, indicating that the hives that were not fed with the substitute showed a higher frequency of pollen of this plant when compared with those who had the artificial diet. The results suggest that supplying with pollen substitute, before and during Stryphnodendron adstringens flowering, is important in reducing the effects of Brazilian sac brood disease.

A cria ensacada brasileira é uma das piores enfermidades de abelhas Apis mellifera L. africanizadas, principalmente do Sudeste do Brasil. Ela afeta o desenvolvimento das larvas, após serem alimentadas pelas abelhas nutrizes com o pólen do barbatimão (Stryphnodendron polyphyllum e Stryphnodendron adstringens), ocasionando a morte entre os estágios de pré-pupa e pupa. O objetivo deste trabalho foi verificar o efeito do substituto de pólen na redução da mortalidade da cria ensacada brasileira durante o florescimento do Stryphnodendron adstringens. Foram utilizados dois tratamentos: as colmeias do tratamento 1 receberam semanalmente substituto de pólen (mistura de farinha de soja, fubá e farinha de trigo em proporções iguais). As colmeias do tratamento 2 não receberam o substituto de pólen, tendo como único alimento o pólen que encontravam na natureza. As colmeias alimentadas apresentaram diferença significativa de 93,5% de viabilidade de sobrevivência de cria em relação às não alimentadas, que apresentaram 80,4% de sobrevivência. A frequência de pólen S. adstringens nos coletores de pólen, no tratamento 1, foi 0,21. Entretanto, no Tratamento 2, foi de 4,38, indicando que as colmeias que não se alimentaram com o substituto apresentaram maior frequência do pólen dessa planta, quando comparadas com as que dispunham da dieta artificial. Esse manejo sugere que a oferta do substituto de pólen, antes e durante a florada do Stryphnodendron adstringens, é importante na redução dos efeitos da cria ensacada brasileira em enxames de abelhas africanizadas.

RESUMO

Species' geographic ranges are usually considered as basic units in macroecology and biogeography, yet it is still difficult to measure them accurately for many reasons. About 20 years ago, researchers started using local data on species' occurrences to estimate broad scale ranges, thereby establishing the niche modeling approach. However, there are still many problems in model evaluation and application, and one of the solutions is to find a consensus solution among models derived from different mathematical and statistical models for niche modeling, climatic projections and variable combination, all of which are sources of uncertainty during niche modeling. In this paper, we discuss this approach of ensemble forecasting and propose that it can be divided into three phases with increasing levels of complexity. Phase I is the simple combination of maps to achieve a consensual and hopefully conservative solution. In Phase II, differences among the maps used are described by multivariate analyses, and Phase III consists of the quantitative evaluation of the relative magnitude of uncertainties from different sources and their mapping. To illustrate these developments, we analyzed the occurrence data of the tiger moth, Utetheisa ornatrix (Lepidoptera, Arctiidae), a Neotropical moth species, and modeled its geographic range in current and future climates.

A distribuição geográfica das espécies tem sido considerada como a unidade básica em macroecologia e biogeografia, mas ainda há dificuldades em mensurá-la de forma adequada, por diferentes razões. Há cerca de 20 anos atrás, os pesquisadores começaram a utilizar dados locais da ocorrência das espécies para estimar essas distribuições utilizando modelos de nicho ecológico. Entretanto, ainda há uma série de problemas na avaliação dos modelos e em suas aplicações, e uma das soluções é utilizar um consenso de diferentes modelos, projeções climáticas, cenários de emissão e combinação de variáveis, que são fontes de incerteza durante o processo de modelagem de nicho. Neste artigo nós discutimos essa abordagem de consenso e a dividimos em três fases, com níveis crescentes de complexidade. A Fase I é simplesmente a combinação de mapas e a obtenção e interpretação de um único mapa de consenso. A Fase II envolve a descrição das diferenças entre os mapas utilizando técnicas de análise multidimensional, enquanto que a Fase III consiste em analisar quantitativamente e mapear a magnitude relativa das diferentes fontes de incerteza. A fim de ilustrar essa abordagem, nós analisamos dados de ocorrência de Utetheisa ornatrix (Lepidoptera, Arctiidae), uma mariposa distribuída na região Neotropical, modelando sua distribuição geográfica com base em dados climáticos atuais e projeções de mudança climática.