Drosophila suzukii (Matsumura) is a species native to Western Asia that is able to pierce intact fruit during egg laying, causing it to be considered a fruit crop pest in many countries. Drosophila suzukii have a rapid expansion worldwide; occurrences were recorded in North America and Europe in 2008, and South America in 2013. Due to this rapid expansion, we modeled the potential distribution of this species using the Maximum Entropy Modeling (MaxEnt) algorithm and the Genetic Algorithm for Ruleset Production (GARP) using 407 sites with known occurrences worldwide and 11 predictor variables. After 1000 replicates, the value of the average area under the curve (AUC) of the model predictions with 1000 replicates was 0.97 for MaxEnt and 0.87 for GARP, indicating that both models had optimal performances. The environmental variables that most influenced the prediction of the MaxEnt model were the annual mean temperature, the maximum temperature of the warmest month, the mean temperature of the coldest quarter and the annual precipitation. The models indicated high environmental suitability, mainly in temperate and subtropical areas in the continents of Asia, Europe and North and South America, where the species has already been recorded. The potential for further invasions of the African and Australian continents is predicted due to the environmental suitability of these areas for this species.

Drosophilidae is one of the most representative families of insects that occurs in fungal fruiting bodies of Basidiomycetes; however, the diversity and community structure of mycophagous Drosophilidae in the Neotropical region is poorly known. The aims of the present study were to describe the diversity of mycophagous Drosophilidae and to investigate its colonization of fungal hosts in a forest of southern Brazil. From 120 fungal samples (patches of mushrooms) of 17 Basidiomycetes genera, fl ies were recorded emerging from 70 samples and collected in adult stages of 25 fungal samples, for a total of 4897 drosophilids belonging to 31 species and 5 genera. Drosophila Fallén was the most species-rich genus, whereas Hirtodrosophila Duda was the dominant genus. Studies performed in the Holarctic region indicate that mycophagous drosophilid have generalist habits; however, our results showed that most drosophilids use fewer than two fungal hosts, and most species of Hirtodrosophila and Leucophenga were restricted to abundant fungal species, suggesting a specialization for these resources. The most specialized fauna emerged from Auricularia, which was the most frequent fungal genus in our collection, and this result supports the assumption that specialization depends on the availability of fungal resources over time.

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Anthropogenic habitat fragmentation directly affects ecological processes, leading to negative biodiversity impacts for insects and other biota. Increased edge effects are one consequence of fragmentation, and may alter the composition or abundance of species in the remaining habitat fragments. Understanding the ways in which edge effects impact upon the biota is essential for conservation decision-making in fragmented landscapes. Therefore, the aim of this study was to analyze the seasonal patterns of abundance, richness, and composition of Drosophilidae in a Restinga forest fragment in the extreme south of Brazil, as a function of the distance from the edge to the interior of the fragment. The data were analyzed using SIMPER analyses, which showed that the edge and the forest interior were most dissimilar during winter, followed by spring, autumn and summer. An NMDS and the SIMPER analyses showed that the lower dissimilarity between the edge and interior in spring, autumn and summer, compared to winter, is driven by immigration of individuals from outside of the forest fragment. Furthermore, some species were asymmetrically distributed in the fragment, with some species restricted to the edge of the fragment and others to the interior. This information aids in the understanding of the functioning and dynamics of fragmentation, which is fundamental for the maintenance and integrity of environments and their fauna.

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