Müller's theory of warning color and mimicry, despite forming a textbook example of frequency-dependent selection, has rarely been demonstrated in the wild. This may be largely due to the practical and statistical difficulties of measuring natural selection on mobile prey species. Here we demonstrate that this selection acts in alpine beetle communities by using tethered beetles

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This pest survey card was prepared in the context of the EFSA mandate on plant pest surveillance (M‐2017‐0137) at the request of the European Commission. Its purpose is to guide the Member States in preparing data and information for Thaumatotibialeucotreta surveys. These are required to design statistically sound and risk‐based pest surveys, in line with current international standards.Thaumatotibialeucotreta is a clearly defined taxonomic entity,currently absent from the EU and surveys would thus be aimed at substantiating pest freedom. In the EU, T. leucotretais expected to be able to become established outdoors in the southernmost parts and indoors in other areas where susceptiblecrops are grown in greenhouses only if there is a year‐round availability of fruit. The most likely introduction of T.leucotreta would be via transport of infested fruit or cut flowers. Imports of fruit of the major host plants iscurrently subject to specific measures aiming to prevent entry of the pest into the EU.Thaumatotibialeucotreta is a moderate disperser; the maximum annual spread distance is estimated to be approximately 1.5 km. Thaumatotibialeucotreta is a highly polyphagous species and a large number of hosts are cultivated in the EU. The recommended hosts for detection surveys in the EU would be the main hosts that are grown on a large scale (e.g. Capsicum spp., Citrus spp. and Prunus spp.). Surveys should be based on a trapping strategy and target the adult moths. Both morphological and molecular methods are available for the identification of the pest.

BackgroundWithin the Coleoptera, the largest order in the animal kingdom, the exclusively herbivorous Chrysomelidae are recognized as one of the most species rich beetle families. The evolutionary processes that have fueled radiation into the more than thirty-five thousand currently recognized leaf beetle species remain partly unresolved. The prominent role of leaf beetles in the insect world, their omnipresence across all terrestrial biomes and their economic importance as common agricultural pest organisms make this family particularly interesting for studying the mechanisms that drive diversification. Here we specifically focus on two ecotypes of the alpine leaf beetle Oreina speciosissima (Scop.), which have been shown to exhibit morphological differences in male genitalia roughly corresponding to the subspecies Oreina speciosissima sensu stricto and Oreina speciosissima troglodytes. In general the two ecotypes segregate along an elevation gradient and by host plants: Oreina speciosissima sensu stricto colonizes high forb vegetation at low altitude and Oreina speciosissima troglodytes is found in stone run vegetation at higher elevations. Both host plants and leaf beetles have a patchy geographical distribution. Through use of gene sequencing and genome fingerprinting (AFLP) we analyzed the genetic structure and habitat use of Oreina speciosissima populations from the Swiss Alps to examine whether the two ecotypes have a genetic basis. By investigating a wide range of altitudes and focusing on the structuring effect of habitat types, we aim to provide answers regarding the factors that drive adaptive radiation in this phytophagous leaf beetle.ResultsWhile little phylogenetic resolution was observed based on the sequencing of four DNA regions, the topology and clustering resulting from AFLP genotyping grouped specimens according to their habitat, mostly defined by plant associations. A few specimens with intermediate morphologies clustered with one of the two ecotypes or formed separate clusters consistent with habitat differences. These results were discussed in an ecological speciation framework.ConclusionsThe question of whether this case of ecological differentiation occurred in sympatry or allopatry remains open. Still, the observed pattern points towards ongoing divergence between the two ecotypes which is likely driven by a recent shift in host plant use.