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The first record of the Asian/yellow-legged hornet (Vespa velutina) in Ireland was reported in April 2021, when a single female individual was discovered in Dublin. Vespa velutina has been present in mainland Europe since 2004 and in the UK since 2016 and poses an enormous threat to European apiculture and bee-mediated pollination services. Three mitochondrial genes were sequenced from the Irish specimen to determine whether the specimen originated from the established European population or signified a new point of entry from its native range in China. Additionally, specimens from Portugal, Spain, France, Germany, and the Channel Islands were sequenced at these three genes to build on previous studies which have asserted, based solely on Cytochrome Oxidase 1 (COI) analysis, that the entire range of V. velutina in Europe represents a single invasion which has proliferated since the first record in France. Further data were retrieved from GenBank for comparison. Results reveal that the mtDNA lineage observed in Dublin is the same as that seen throughout Europe, and therefore the arrival of this species in Ireland likely represents a further spread of the ongoing European invasion. [ABSTRACT FROM AUTHOR]

While the value of linear farm habitats for the protection and enhancement of farmland biodiversity in general is known, less is understood about their contribution to Diptera, especially those with different ecological requirements. In this study, we examined the impact of a range of linear farm habitats in agricultural grassland on Syrphidae and Sciomyzidae (Diptera) both of which provide important ecosystem services.Species richness and abundance for each family were measured across five different linear habitat types (dense and open hedgerows with/without adjacent watercourses and watercourses only). While dense hedgerows with adjacent watercourses showed the greatest numbers of Syrphidae species and individuals, open hedgerows with adjacent watercourses had significantly more Sciomyzidae species and individuals than dense hedgerows without watercourses or open hedgerows only.Syrphidae species richness was significantly correlated with the flowering plant species richness of linear habitats, while Sciomyzidae species richness was correlated with a habitat quality score for grasslands adjacent to the linear habitats.Overall, Syrphidae and Sciomyzidae species richness and community composition are shown to reflect a farming intensity gradient with significantly greater species richness for both families on extensive farms.Our results suggest that different dipteran taxa which utilise linear habitats may have different requirements. This has implications for future agri‐environmental schemes in the context of how we assess the conservation value of linear habitats on farmlands. [ABSTRACT FROM AUTHOR]

The intensification of farming practices, along with the loss and fragmentation of semi‐natural habitats within agricultural areas, has contributed significantly to insect decline worldwide including flower‐visiting aculeate Hymenoptera.In this study aculeate Hymenoptera were collected using bi‐directional Malaise traps placed along farmland linear habitats across a range of farming intensities. The aim was to further our understanding of the value of farmland linear habitats to this insect group and in particular the Vespinae, an understudied subfamily.Overall, significantly greater aculeate Hymenoptera species richness was found on extensive than on intermediate and intensive farms. Significantly more species and specimens were collected on the side of the traps adjacent to the linear habitats compared to the side which opened onto the fields. Aculeate Hymenoptera species richness was also significantly greater in dense hedgerows than in open hedgerows. Furthermore, two out of six Vespinae species, Vespula rufa and Vespula vulgaris, had significantly more individuals on extensive than intensive farms.This study highlights that low‐intensity farming practices and farmland linear habitats, especially dense hedgerows, may enhance aculeate Hymenoptera occurrence in agricultural areas. It also demonstrates that Malaise traps set up along linear habitats across a range of farming intensities can make a significant contribution to knowledge regarding the biodiversity value of such areas. Given that selected Vespinae species follow similar trends to aculeate Hymenoptera, the possibility of using them as simple biodiversity indicators is worthy of further exploration. [ABSTRACT FROM AUTHOR]

Background: Animal colours and patterns commonly play a role in reducing detection by predators, social signalling or increasing survival in response to some other environmental pressure. Different colour morphs can evolve within populations exposed to different levels of predation or environmental stress and in some cases can arise within the lifetime of an individual as the result of phenotypic plasticity. Skin pigmentation is variable for many terrestrial slugs (Mollusca: Gastropoda), both between and within species. The Kerry spotted slug Geomalacus maculosus Allman, an EU protected species, exhibits two distinct phenotypes: brown individuals occur in forested habitats whereas black animals live in open habitats such as blanket bog. Both colour forms are spotted and each type strongly resembles the substrate of their habitat, suggesting that G. maculosus possesses camouflage. Results: Analysis of digital images of wild slugs demonstrated that each colour morph is strongly and positively correlated with the colour properties of the background in each habitat but not with the substrate of the alternative habitats, suggesting habitat-specific crypsis. Experiments were undertaken on laboratory-reared juvenile slugs to investigate whether ultraviolet (UV) radiation or diet could induce colour change. Exposure to UV radiation induced the black (bog) phenotype whereas slugs reared in darkness did not change colour. Diet had no effect on juvenile colouration. Examination of skin tissue from specimens exposed to either UV or dark treatments demonstrated that UV-exposed slugs had significantly higher concentrations of black pigment in their epithelium. Conclusions: These results suggest that colour dimorphism in G. maculosus is an example of phenotypic plasticity which is explained by differential exposure to UV radiation. Each resulting colour morph provides incidental camouflage against the different coloured substrate of each habitat. This, to our knowledge, is the first documented example of colour change in response to UV radiation in a terrestrial mollusc. Pigmentation appears to be correlated with a number of behavioural traits in G. maculosus, and we suggest that understanding melanisation in other terrestrial molluscs may be useful in the study of pestiferous and invasive species. The implications of colour change for G. maculosus conservation are also discussed. [ABSTRACT FROM AUTHOR]