Descriptions are given of three new species of Merodon Meigen (Diptera: Syrphidae) in the nigritarsis species group from the Middle East: Merodon angustus Vujić et Radenković n. sp., Merodon hakkariensis Vujić et Radenković n. sp. and Merodon quadraticus Vujić et Radenković n. sp. In addition, diagnostic characters are given for the nigritarsis group and distribution maps are presented for the new species and closely related taxa.

Hoverflies are a valuable group of species in need of conservation and monitoring, due to their large contribution to pollination, biological control, and role as indicators of ecosystem change. Though hoverflies are a well-known group of insects, there has been little documentation of their current conservation status. Using long-term hoverfly monitoring data, this study reports on their prevalence in Serbia and presents priority areas for their conservation. An expert-generated, criteria-driven approach was used to identify core areas for conservation of hoverflies, named Prime Hoverfly Areas (PHA); 34% of the identified area lies outside of a national protection area (NPA) network. A systematic conservation approach (gap and irreplaceability analysis) was then applied to evaluate: 1) sufficiency of the NPA for hoverfly conservation, and 2) degree of improvement in hoverfly conservation conferred by the expert-generated PHA network. The networks were evaluated for the achievement of predefined representation targets for each of the 155 hoverfly species identified as important for conservation. We found that the NPA network is insufficient, as it does not cover the ranges of 18% of considered species. The area of the proposed PHA outside of the NPA is small (1.36% of the national territory), but its protection would greatly improve hoverfly conservation by increasing the inclusion of hoverfly habitats for previously unprotected species and by including hoverfly biodiversity hot spots. The suggested PHA network was then compared to a similarly designed habitat network aimed to conserve butterflies. There was partial overlap between the two networks, highlighting the importance of considering multiple groups in planning comprehensive conservation strategies for pollinators.

A new hoverfly species, Cheilosia barbafacies Vujić & Radenković sp. n. (Diptera, Syrphidae), is described and distinguished from the closely related species Cheilosia pascuorum Becker, 1894, based on material collected from the mountains of the Balkan Peninsula. Diagnostic characteristics and an identification key for the members of the proxima group of Cheilosia s. str., including the new taxon, are provided.

Climate change is now considered a significant threat to terrestrial biodiversity. Species distribution models (SDMs) are among the modern tools currently used to assess the potential impacts of climate change on species. Pipiza Fallén, 1810 is a well known aphidophagous hoverfly genus (Diptera, Syrphidae) at the European level, for which sampling has been conducted across the region, and long-term databases and geo-referenced datasets have been established. Therefore, in this work, we investigated the potential current distributions of the European species of this genus and their response to future climate change scenarios, as well as evaluated stability in their ranges and potential changes in species-richness patterns. We applied three climate models (BCC_CSM1.1, CCSM4, HadGEM2-ES) to four representative concentration pathways (RCP 2.6, RCP 4.5, RCP 6.0, RCP 8.5) for two time frames (2050 and 2070). Our results show that the distribution of most Pipiza species may slightly differ under different climate models. Most Pipiza species were predicted not to be greatly affected by climate change, maintaining their current extent. Percentages of stable areas will remain high (above 50%) for the majority of studied species. According to the predicted turnover of species, northern Europe, could become the richest in terms of species diversity, thus replacing Central Europe as the current hot spot.

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Seven species of the genus Pipiza, collected throughout the southern and western Balkans, were used for the analysis of habitat preferences and potential geographical distribution on the Balkan Peninsula. The analyzed species show a wide and uneven distribution across the delineated geographical-biogeographical regions. The highest number of species noted is from two regions - the Dinaric mountain chain and the Pannonian and subpannonian regions (seven and six). Land cover patch analysis revealed that forests dominate the landscape surroundings of the analyzed species. “Presenceonly models” developed by Maxent support the understanding of the distribution and ecology of each analyzed species. The low probability values of current potential distribution correspond to large non-forested and fragmented forest areas, where, on the other hand, relatively high probabilities overlap with areas of deciduous forests across the peninsula. Results confirm species preference to forest landscapes and emphasize the need for local scale analysis. The studies are of importance in developing regional monitoring schemes and conservation strategies

Overwinter survival of hibernators is directly influenced by the fat reserves accumulated during the active season. The European ground squirrel, Spermophilus citellus, an endangered flagship species of the open grasslands of central and southeastern Europe, is no exception. Considering anthropogenic changes affecting its habitats in northern Serbia, we studied the species? feeding habits by subjecting its feces to microhistological examination. In addition to identifying plant remains in the feces, we examined the vegetation of the four study sites located inside a local mosaic of steppe and saline pastures. Our findings indicate that these remaining European ground-squirrel sites are diverse and stable grasslands covered by native flora that represents a complete dietary base for the species. The diet is dominated by a small number of plant species, specifically Achillea millefolium, legumes and grasses, with sporadic contributions from a number of other species. The diet of S. citellus also differs by location and season in that grasses dominate during the early season, while A. millefolium takes precedence later in the year. This dietary information is essential for the development of future species and habitat management strategies. In light of the predicted impact of climate change on grasslands in northern Serbia, our findings will be instrumental for translocations and conservation actions in the future.

Understanding the spatial and temporal effects of variable environmental conditions on demographic characteristics is important in order to stop the decline of endangered-species populations. To capture interactions between a species and its environment, in this work the demographic traits of the European ground squirrel (EGS), Spermophilus citellus, were modeled as a function of agricultural landscape structure. The habitat suitability index was determined for 20 localities within the study area based on habitat use, management and type. After mapping the habitat patch occupancy in the field, crop cover maps, the average normalized difference vegetation index (NDVI) and automated water extraction index (AWEI) were obtained from satellite images covering the period 2013-2015. This data was used to develop population-level generalized linear models (GLMs) and individual-level conditional mixed-effects models (GLMMs) in R package Ime4, focusing on the key demographic traits of the EGS. The land composition and patch carrying capacity (PCC) are the key determinants of the endangered EGS population size, while system productivity is the main factor influencing individuals' body condition after monitoring for variations across sampling years and age classes. The proposed landscape structural models show that human activities and abiotic factors shape the demographic rates of the EGS. Thus, to conserve threatened species, an appropriate focus on the spatial adaptation strategies should be employed.