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The turbulent Tertiary and Quaternary history of Europe and the Ponto-Caucasus has had a strong impact on its biota, resulting in unusual patterns of speciation, diversification, and dispersal. Our study reveals the Late-Tertiary diversification and biogeographic history of Mniophila , a Western Palaearctic endemic moss-inhabiting flightless flea beetle distributed across Europe and the Ponto-Caucasus. We assembled samples across the whole range of the genus except Crimea. Based on a molecular phylogenetic analysis, we found that the diversification of Mniophila started in the Balkan Peninsula, and was followed by at least two independent colonizations of other parts of Europe. The Ponto-Caucasian species are all descendants of a single colonization from the Balkans, followed by species' radiation. The Mniophila beetles are, therefore, one of the first-known cases of the colonization of the Caucasus from Europe. We integrated our DNA data with morphology, allowing us to uncover the cryptic diversity of Mniophila and to revise its European species. We describe Mniophila haveli sp. nov. from the Carpathians and Balkans, M. wroblewskii Wańkowicz, 1880 from Central Europe and the Balkans is restored as a valid species, and M. bosnica Apfelbeck, 1914 is newly recognized as a Dinaric endemic. We reveal an exceedingly large distribution range for M. muscorum (Koch, 1803), which is unusual for a flightless beetle. [ABSTRACT FROM AUTHOR]

Hoverflies (Diptera, Syrphidae) are cosmopolitan, generalist flower visitors and among the most important pollinators after bees and bumblebees. The dronefly Eristalis tenax can be found in temperate and continental climates across the globe, often synanthropically. Eristalis tenax pupae of different generations and different climate zones are thus exposed to vastly different temperatures. In many insects, the ambient temperature during the pupal stage affects development, adult size, and survival; however, the effect of developmental temperature on these traits in hoverflies is comparatively poorly understood. We here reared E. tenax pupae at different temperatures, from 10°C to 25°C, and quantified the effect on adult hoverflies. We found that pupal rearing at 17°C appeared to be optimal, with high eclosion rates, longer wings, and increased adult longevity. Rearing temperatures above or below this optimum led to decreased eclosion rates, wing size, and adult survival. Similar thermal dependence has been observed in other insects. We found that rearing temperature had no significant effect on locomotor activity, coloration or weight, despite evidence of strong sexual dimorphism for each of these traits. Our findings are important as hoverflies are key pollinators, and understanding the effects of developmental temperature could potentially be useful for horticulture. [ABSTRACT FROM AUTHOR]

Prey seldom rely on a single type of antipredator defence, often using multiple defences to avoid predation. In many cases, selection in different contexts may favour the evolution of multiple defences in a prey. However, a prey may use multiple defences to protect itself during a single predator encounter. Such "defence portfolios" that defend prey against a single instance of predation are distributed across and within successive stages of the predation sequence (encounter, detection, identification, approach (attack), subjugation and consumption). We contend that at present, our understanding of defence portfolio evolution is incomplete, and seen from the fragmentary perspective of specific sensory systems (e.g., visual) or specific types of defences (especially aposematism). In this review, we aim to build a comprehensive framework for conceptualizing the evolution of multiple prey defences, beginning with hypotheses for the evolution of multiple defences in general, and defence portfolios in particular. We then examine idealized models of resource trade‐offs and functional interactions between traits, along with evidence supporting them. We find that defence portfolios are constrained by resource allocation to other aspects of life history, as well as functional incompatibilities between different defences. We also find that selection is likely to favour combinations of defences that have synergistic effects on predator behaviour and prey survival. Next, we examine specific aspects of prey ecology, genetics and development, and predator cognition that modify the predictions of current hypotheses or introduce competing hypotheses. We outline schema for gathering data on the distribution of prey defences across species and geography, determining how multiple defences are produced, and testing the proximate mechanisms by which multiple prey defences impact predator behaviour. Adopting these approaches will strengthen our understanding of multiple defensive strategies. [ABSTRACT FROM AUTHOR]

Mimicry is usually understood to be an adaptive resemblance between phylogenetically distant groups of species. In this study, we focus on Batesian and Müllerian mimicry, which are often viewed as a continuum rather than distinct phenomena, forming so-called Batesian-Müllerian mimicry rings. Despite potent defence and wide environmental niche of hornets, little attention has been paid to them as potential models in mimicry research. We propose a Batesian-Müllerian mimicry ring of the Oriental hornet (Vespa orientalis, Hymenoptera: Vespidae) consisting of eight species that coexist in the Mediterranean region. To reveal general ecological patterns, we reviewed their geographical distribution, phenology, and natural history. In accordance with the ‘model-first’ theory, Batesian mimics of this ring occurred later during a season than the Müllerian mimics. In the case of Batesian mimic Volucella zonaria (Diptera: Syrphidae), we presume that temperature-driven range expansion could lead to allopatry with its model, and, potentially, less accurate resemblance to an alternative model, the European hornet (Vespa crabro: Hymenoptera: Vespidae). Colour morphs of polymorphic species Cryptocheilus alternatus (Hymenoptera: Vespidae), Delta unguiculatum (Hymenoptera: Vespidae), Rhynchium oculatum (Hymenoptera: Vespidae), and Scolia erythrocephala (Hymenoptera: Scoliidae) appear to display distinct geographical distribution patterns, and this is possibly driven by sympatry with alternative models from the European hornet (Vespa crabro) complex. General coevolution patterns of models and mimics in heterogenous and temporally dynamic environments are discussed, based on observations of the proposed Oriental hornet mimicry ring. [ABSTRACT FROM AUTHOR]

A new species of fossil hoverfly (Syrphidae: Eristalinae), i.e., Blera miocenica sp. nov. is described from the Early Miocene (Burdigalian) of Bílina mine in the Most Basin, Czech Republic. The species description is based on a well preserved compressed fossil and it represents the first known fossil record of the genus Blera Billberg, 1820 so far. B. miocenica sp. nov. diagnosis is based on the wing venation and other body characters like the coloration pattern of abdomen. The resemblance of the new fossil to extant species of Blera is briefly discussed. The previously suggested palaeoenvironmental conditions at the type locality are in agreement with the knowledge on autecology of recent representatives of the genus Blera (i.e., larval feeding strategy, adult habitat preferences and flower visitation). Thus, we conclude that fossil hoverflies could be a helpful tool for the indication of past habitats. [ABSTRACT FROM AUTHOR]