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Organisms have evolved different defense mechanisms, such as crypsis and mimicry, to avoid detection and recognition by predators. A prominent example is Batesian mimicry, where palatable species mimic unpalatable or toxic ones, such as Clytini (Coleoptera: Cerambycidae) that mimic wasps. However, scientific evidence for the effectiveness of Batesian mimicry in Cerambycids in natural habitats is scarce. We investigated predation of warningly and nonwarningly colored Cerambycids by birds in a temperate forest using beetle dummies. Dummies mimicking Tetropium castaneum , Leptura aethiops , Clytus arietis , and Leptura quadrifasciata were exposed on standing and laying deadwood and monitored predation events by birds over one season. The 20 surveyed plots differed in their structural complexity and canopy openness due to different postdisturbance logging strategies. A total of 88 predation events on warningly colored beetle dummies and 89 predation events on nonwarningly colored beetle dummies did not reveal the difference in predation risk by birds. However, predation risk increased with canopy openness, bird abundance, and exposure time, which peaked in July. This suggests that environmental factors have a higher importance in determining predation risk of warningly and nonwarningly colored Cerambycidae than the actual coloration of the beetles. Our study showed that canopy openness might be important in determining the predation risk of beetles by birds regardless of beetles' warning coloration. Different forest management strategies that often modify canopy openness may thus alter predator–prey interactions. [ABSTRACT FROM AUTHOR]

Climate, topography and the 3D structure of forests are major drivers affecting local species communities. However, little is known about how the specific functional traits of saproxylic (wood‐living) beetles, involved in the recycling of wood, might be affected by those environmental characteristics.Here, we combine ecological and morphological traits available for saproxylic beetles and airborne laser scanning (ALS) data in Bayesian trait‐based joint species distribution models to study how traits drive the distributions of more than 230 species in temperate forests of Europe.We found that elevation (as a proxy for temperature and precipitation) and the proportion of conifers played important roles in species occurrences while variables related to habitat heterogeneity and forest complexity were less relevant. Furthermore, we showed that local communities were shaped by environmental variation primarily through their ecological traits whereas morphological traits were involved only marginally. As predicted, ecological traits influenced species' responses to forest structure, and to other environmental variation, with canopy niche, wood decay niche and host preference as the most important ecological traits. Conversely, no links between morphological traits and environmental characteristics were observed. Both models, however, revealed strong phylogenetic signal in species' response to environmental characteristics.These findings imply that alterations of climate and tree species composition have the potential to alter saproxylic beetle communities in temperate forests. Additionally, ecological traits help explain species' responses to environmental characteristics and thus should prove useful in predicting their responses to future change. It remains challenging, however, to link simple morphological traits to species' complex ecological niches. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Aim: The Rosalia longicorn (Rosalia alpina) is an internationally protected icon of biodiversity associated with old trees and dead wood. Although the beetle regularly exploits several marginal hosts, its preferred main host is European beech (Fagus sylvatica s.l.). Moreover, the geographical ranges of R. alpina and beech closely overlap. To assess whether their spatial association is mirrored in the genetic patterns of both species, we investigated the phylogeography of Rosalia alpina over its entire geographical range and compared it with the known genetic patterns of its hosts. Location: Europe and western Asia. Methods: Using both mitochondrial (COI) and nuclear (14 microsatellite loci) markers, we analysed 148 (444, respectively) individuals from 31 (30, respectively) sites. We constructed a Bayesian Inference tree and a haplotype network, calculated the spatial analysis of molecular variance and assessed the population structure of our dataset using two Bayesian clustering methods (STRUCTURE and BAPS). Results: Mitochondrial markers suggested existence of five clades in R. alpina populations. Two of them were endemic to the Italian mainland, one to Sicily, and another to southern Turkey. The remaining clade probably originated in the Balkans and colonized the rest of the species' range. Nuclear markers supported this division. They also suggested two main recolonization routes from the Balkans; one heading north and then both west and east, the second expanding eastwards as far as the Caucasus. The observed genetic patterns were largely congruent with those of European beech. Main conclusions: The results of both markers were mostly congruent, suggesting at least four potential refugia for R. alpina located in the southernmost parts of its geographical range. Its populations from a large part of Europe and western Asia, however, were genetically poor, dominated by a single haplotype. Phylogeographies of the beetle and its main host seem to be tightly matched, reflecting their common history. [ABSTRACT FROM AUTHOR]

Dispersal ability is among the key factors affecting the survival of species in today’s fragmented landscapes. One of the most straightforward methods to provide direct measures of animal dispersal is telemetry. Despite its merits, this method has rarely been used for saproxylic beetles. In this study, we examined dispersal ability of the Great Capricorn beetle Cerambyx cerdo (Coleoptera: Cerambycidae), an endangered veteran oak specialist. Using a radio-tracking approach, we tracked 26 individuals (15 males and 11 females) equipped with transmitters for 4 to 17 days (median 14). We observed no disturbance of movements or flight problems due to the transmitter. The daily probability of movement by an individual was 64% and the longest displacement in one day was 1498 m for males and 1080 m for females. For 15% of all individuals, the tracking distance covered was >2200 m. Our results indicate that C. cerdo individuals often move among trees over an area of several kilometres. Such findings contrast with previous results based on a mark-recapture study. The relatively high mobility of the species should be reflected in strategies aiming at its conservation. [ABSTRACT FROM AUTHOR]

Knowledge of patterns of genetic diversity in populations of threatened species is vital for their effective conservation. Rosalia longicorn ( Rosalia alpina) is an endangered and strictly protected beetle. Despite a marked decline in part of its range, the beetle has recently expanded to the lowlands of Central Europe. To facilitate a better understanding of the species' biology, recent expansion and more effective conservation measures, we investigated patterns of genetic structure among 32 populations across Central and South-east Europe. Eight microsatellite loci and a partial mitochondrial gene (cytochrome c oxidase subunit I) were used as markers. Both markers showed a significant decline in genetic diversity with latitude, suggesting a glacial refugium in north-western Greece. The cluster analysis of the nuclear marker indicated the existence of two genetically distinct lineages meeting near the border between the Western and Eastern Carpathians. By contrast, one widespread mt DNA haplotype was dominant in most populations, leading to the assumption that a rapid expansion of a single lineage occurred across the study area. The genetic differentiation among populations from the north-western part of the study area was, however, surprisingly low. They lacked any substructure and isolation-by-distance on a scale of up to 600 km. This result suggests a strong dispersal capacity of the species, as well as a lack of migration barriers throughout the study area. That the lowland populations are closely related to those from the nearby mountains indicates repeated colonization of the lowlands. Our results further suggest that R. alpina mostly lives in large, open populations. Large-scale conservation measures need to be applied to allow for its continued existence. [ABSTRACT FROM AUTHOR]