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Results 181 to 210 of 1442:

Forecasting the spread associated with climate change in Eastern Europe of the invasive Asiatic flea beetle, Luperomorpha xanthodera (Coleoptera: Chrysomelidae)Original article

Mattia IANNELLA, Paola D'ALESSANDRO, Maurizio BIONDI

Eur. J. Entomol. 117: 130-138, 2020 | DOI: 10.14411/eje.2020.015

The current climate has facilitated biological invasions worldwide, with the spread of invasive species accelerating over the last few decades. Introductions of species are often accidental and facilitated by many factors, including intercontinental trade. In this paper, we explore the secondary range of an adventive flea beetle native to Asia, Luperomorpha xanthodera, which was recently found in many European countries on several occurrences. This species has detrimental effects mainly on ornamental plants, being destructive to leaves and flowers, which can have serious negative economic consequences. We inferred current and future potential distribution of this alien species using Ecological Niche Modelling (ENM) and analysed the future increase in suitable areas in European countries. Suitable climatic conditions for L. xanthodera are assumed to be similar to that in areas where this species currently occurs, which includes Ireland and some Balkan countries, where the species is not recorded yet. In the future, a North-eastern expansion is predicted, with many countries currently lacking suitable climatic conditions for L. xanthodera becoming suitable and potentially colonizable by this species. The geographic trend revealed and quantified in our analysis follows the increase in the mean temperature in the coldest quarter of the year, which is predicted to rise in the next 30 years. This will result in this species spreading from south-western Europe to North-Eastern countries, such as Poland, Ukraine, Romania, Belarus and Latvia, which should adopt preventive measures to avoid the accidental introduction of L. xanthodera.

Taxonomic revision of the genus Angulaphthona (Coleoptera: Chrysomelidae: Galerucinae: Alticini)Original article

Maurizio BIONDI, Paola D'ALESSANDRO

Eur. J. Entomol. 115: 30-44, 2018 | DOI: 10.14411/eje.2018.005

A revision of the genus Angulaphthona Bechyné, 1960 is provided, with a description of Angulaphthona confusa sp. n. from the Democratic Republic of Congo, and A. rossii sp. n. from Sierra Leone. The following synonymies are proposed: Angulaphthona latipennis (Pic, 1921) = A. latipennis zambeziensis (Bechyné, 1959) syn. n. and Angulaphthona pelengensis Bechyné, 1960 = A. exalta Bechyné, 1960 syn. n. The precedence of the name pelengensis is discussed. Angulaphthona violaceomicans (Chen, 1936) comb. n. (transferred from Aphthona) from Sri Lanka is established, and some hypotheses to explain the presence of the genus outside Africa are put forward. A key to the seven known species is supplied, with microphotographs of diagnostic characters, including male and female genitalia.

Barrier pitfall traps increase captures of ground beetles (Coleoptera: Carabidae) on exposed riverine sedimentsOriginal article

Scott HORN

Eur. J. Entomol. 117: 76-82, 2020 | DOI: 10.14411/eje.2020.008

Exposed riverine sediments are unique riparian environments that exhibit high biodiversity and harbor many specialist species. Ground beetles are the most well studied inhabitants within these environments where they are often sampled using pitfall traps. In order to develop conservation measures for species occupying these habitats a logical first step is to refine sampling methods so that proper biodiversity assessments can be carried out. To that end, the effectiveness of two pitfall trap designs (standard trap vs. barrier trap) was evaluated. Over three sampling periods we collected 5,186 individuals represented by 43 species. Barrier traps proved to be superior, yielding significantly greater numbers of individuals (n = 3,456 vs. 1,730) than standard traps. Additionally, we collected more ground beetle species (37 vs. 30) in barrier traps than in standard pitfall traps. This study supports the rationale for deployment of more than one trap design to avoid deficiencies exhibited by a single type.

Distribution of Finnish mound-building Formica ants (Hymenoptera: Formicidae) based on using a citizen science approachOriginal article

Jouni SORVARI

Eur. J. Entomol. 118: 57-62, 2021 | DOI: 10.14411/eje.2021.007

The distance from southern Italy to Denmark is about the same as the length of Finland from south to north. A study of the biogeography of insects, such as ants, would take a lot of effort and funding to sample the whole area. Here, a citizen science approach is used to obtain distribution records for mound-building Formica ants in Finland. This resulted in samples from 2,434 ant nests, of which 2,363 were for nests of the target species group. The data obtained helps define the northern limits of the species in Finland and resulted in three new records for F. suecica Adlerz, 1902, which is a red-listed species in Finland. In addition, as a by-catch, a new imported species dispersed in a peculiar way was recorded in Finland: Lasius emarginatus (Olivier, 1792). Volunteer citizens are potential research assistants in the science of entomology.

Contribution of population-level phenotypic plasticity to the invasiveness of Zaprionus indianus (Diptera: Drosophilidae)Original article

Nicolás José LAVAGNINO, Marcos IMBERTI, Nicolás FLAIBANI, Victoria Estefanía ORTIZ, Juan José FANARA

Eur. J. Entomol. 117: 118-128, 2020 | DOI: 10.14411/eje.2020.013

Zaprionus indianus is a species of fly native to the Afrotropical biogeographic region, which around twenty years ago invaded the American continent. Several studies have shown that local adaptation and phenotypic plasticity of an invasive species in its native range could favour the colonization of new environments. Zaprionus indianus is a holometabolous generalist polyphagous species that breeds and feeds on the fruits of several different species, which constitute different environments. In this context, we performed a comparative analysis of the phenotypic plasticity of morphological and life history traits in response to seven different breeding environments (i.e. different breeding fruits). The comparison was of native (Africa) vs. invaded range (South America) wild-derived populations. The population-level phenotypic plasticity values related to heterogeneity in different breeding environments for most traits analysed were higher for one of the native range population. This differentiation was also recorded for the ranking across breeding environments of developmental time and wing length mean phenotypic values. In addition, mean phenotypic values pooled across fruit treatments were larger for individuals from the invaded range, which suggests local adaptation. Results define a scenario in which, although not for all the populations analysed, phenotypic plasticity contributes to the invasiveness and local adaptation in native range population of Z. indianus.

Effect of the energy content of diets on the development and quality of the fat reserves of larvae and reproduction of adults of the black soldier fly, Hermetia illucens (Diptera: Stratiomyidae)Original article

Bogdan GEORGESCU, Dănuț STRUȚI, Tudor PĂPUC, Vasile CIGHI, Anca BOARU

Eur. J. Entomol. 118: 297-306, 2021 | DOI: 10.14411/eje.2021.030

Hermetia illucens is a sustainable and an increasingly bioeconomical source of nutrients for farm animals. It is still necessary, however, to improve our knowledge of the biological features of this species in order to maximize its use. The aims of this research were to evaluate the effect of the energy level of rearing diets on its body weight and fat-body reserves. The quantity and quality of the fats storred by the non-feeding stages of this insect and its reproductive performances were also studied. A control diet (CD - Gainesville diet) and three diets with progressively greater energy contents (kcal/kg ME) were formulated. The increase was achieved by including different amounts of maize, 40% (ED1), 60% (ED2) and 80% (ED3), in these three diets. Abother diet (ED4) consisted of fruit and vegetable waste. The results indicate that the body weight of larvae, prepupae, pupae and adult flies, as well as fat content of the larvae increased significantly (p ˂ 0.01) with increase in the energy content of the diets. There was a positive Pearson correlation between energy content of diets and body weight of adult flies. The heaviest egg clutches with the highest number of eggs/clutch (p ˂ 0.01) were laid by flies reared on the diets with the highest energy content. The quality of the fat stored by larvae did not influence the weight and number of egg laid.

Relationships between the geographic distribution of phytophagous insects and different types of vegetation: A case study of the flea beetle genus Chaetocnema (Coleoptera: Chrysomelidae) in the Afrotropical region

Maurizio BIONDI, Fabrizia URBANI, Paola D'ALESSANDRO

Eur. J. Entomol. 112 (2): 311-327, 2015 | DOI: 10.14411/eje.2015.040

This study analyses the geographic distributions of 95 endemic and sub-endemic species of Chaetocnema (Coleoptera: Chrysomelidae) found in Sub-Saharan Africa and Madagascar, in order to compare and correlate their pattern of the geographic range (chorotype) and the distribution of terrestrial ecosystems in Africa and Madagascar. The data compiled for the species of Chaetocnema are based on records for 1639 collecting localities. Most of the species of Chaetocnema have restricted geographical ranges (67.3%), whereas relatively few species (11.6%) are very widely distributed. The latitudinal and longitudinal gradients in the numbers of species reveal that the highest levels of species richness occur in the Equatorial Belt and Southern Africa. Species of Chaetocnema in Sub-Saharan Africa have a clear preference for grassland and the wide-open environment associated with savannah. However, forest ecosystems are also important for numerous species, particularly in Madagascar. Several endemic species are associated with the Mediterranean vegetation in the southern part of West Africa. Species of Chaetocnema are generally associated with a limited number of vegetation types within the Afrotropical region. A cluster analysis based on calculating the squared Euclidean distance and using the WARD clustering method revealed a significant correlation between the chorotype and the vegetation types associated with each species. Finally, certain species of Chaetocnema that are characteristic of specific types of vegetation and/or indicators of biodiversity hotspots in Sub-Saharan Africa and Madagascar are highlighted.

Functional responses and intraspecific competition in the ladybird Harmonia axyridis (Coleoptera: Coccinellidae) provided with Melanaphis sacchari (Homoptera: Aphididae) as preyOriginal article

Pengxiang WU, Jing ZHANG, Muhammad HASEEB, Shuo YAN, Lambert KANGA, Runzhi ZHANG

Eur. J. Entomol. 115: 232-241, 2018 | DOI: 10.14411/eje.2018.022

Functional responses at each developmental stage of predators and intraspecific competition associated with direct interactions among them provide insights into developing biological control strategies for pests. The functional responses of Harmonia axyridis (Pallas) at each developmental stage of Melanaphis sacchari (Zehntner) and intraspecific competition among predators were evaluated under laboratory conditions. The results showed that all stages of H. axyridis displayed a type II functional response to M. sacchari. Based on Holling's disc equation, the instantaneous searching rates were highest (a) and handling time was shortest (Th) of fourth instar larvae (a = 0.8818; Th = 3.9 min) and female adults (a = 0.9881; Th = 3.0 min) at larval and adult stages, respectively. The coefficients of mutual interference (m) assessed by the intraspecific competition equation were higher for fourth instar larvae (m = 0.4764) and female adults (m = 0.4183). The present study indicates that fourth instar and female adult were more effective stages of H. axyridis in the context of biological control but suitable predator densities need to be considered before natural enemy release.

Foraging behaviour of Scymnus syriacus (Coleoptera: Coccinellidae) provided with Aphis spiraecola and Aphis gossypii (Hemiptera: Aphididae) as prey: Functional response and prey preferenceOriginal article

Mahboobeh MORADI, Mahdi HASSANPOUR, Seyed Ali Asghar FATHI, Ali GOLIZADEH

Eur. J. Entomol. 117: 83-92, 2020 | DOI: 10.14411/eje.2020.009

Scymnus syriacus Marseul is one of the most important biocontrol agents of aphids in citrus orchards. Understanding the efficiency and host specificity of natural enemies can help improve their effectiveness as biological control agents of particular pests. In this study, the functional response, preference and switching behaviour of different stages of S. syriacus feeding on Aphis spiraecola Patch and Aphis gossypii Glover, on orange leaves, were studied under laboratory conditions of 27 ± 2°C, 65 ± 5% RH and a photoperiod of 16L : 8D. The results indicate that 4th instar larvae and adult males and females of this predator exhibit a type II functional response when offered different numbers (3, 5, 7, 10, 20, 30, 40, 60 and 80) of both A.spiraecola and A. gossypii. Adult females had significantly higher attack rates (a) on both species of aphids. Handling times (Th) of adult male predators on A. spiraecola and those of 4th instar larvae on A. gossypii were shorter than that of the other stages. In no-choice preference experiments, adult females fed equally on both species of aphid, but the 4th instar larvae preferred A. gossypii. In switching experiments, prey selection was evaluated by simultaneously presenting different ratios (30 : 50, 40 : 40 and 50 : 30) of the two aphids, A. spiraecola : A. gossypii, to the predator. The 4th instar larvae and adult females of S. syriacus showed higher preference for A. gossypii at each ratio offered (except adult females offered the 50 : 30 ratio). Based on their foraging behaviour 4th instar larvae and adult females of S. syriacus are suitable for use in integrated management of citrus aphids.

Urbanisation and forest size affect the infestation rates of plant-galling arthropods and damage by herbivorous insectsOriginal article

Sandro MEYER, Hans-Peter RUSTERHOLZ, Bruno BAUR

Eur. J. Entomol. 117: 34-48, 2020 | DOI: 10.14411/eje.2020.004

Urbanisation is increasing globally and is considered to be a main driver of environmental change. Urbanisation-related factors include reduced habitat size and increased spatial isolation of the remaining habitats. As a consequence, the dynamics of plant and animal populations may change, which in turn might influence the quality and quantity of plant resources. Thus, urbanisation has the potential to disturb plant-animal interactions such as herbivory or galling. In the urban-rural setting of Basel (Switzerland), we aimed to assess whether the degree of urbanisation and forest size influence plant-galling infestation rates and leaf damage by mining and chewing arthropods on three tree species (sycamore, beech, and ash). We recorded species-specific responses to the degree of urbanisation and forest size. Gall infestation rate on sycamore leaves was affected by urbanisation but not by forest size. In contrast, gall infestation rates of beech gall midges responded sensitively to increasing urbanisation and decreasing forest size. The total leaf area damage caused by mining and chewing arthropods on sycamore was influenced by urbanisation and increased with increasing forest size. Leaf area damage by miners in beech tended to be affected by the degree of urbanisation, but not in ash. Urbanisation and forest size have the potential to alter herbivorous insect abundances. However, the effects depend on tree species and herbivore guild.

Influence of forest decline on the abundance and diversity of Raphidioptera and Mecoptera species dwelling in oak canopiesOriginal article

Alexis VINCENT, Pierre TILLIER, Cécile VINCENT-BARBAROUX, Christophe BOUGET, Aurélien SALLÉ

Eur. J. Entomol. 117: 372-379, 2020 | DOI: 10.14411/eje.2020.041

Trees in a state of decline exhibit a reduced foliage density and accumulate dead branches in their crowns. Consequently, forest decline can markedly affect both the habitats and sources of food for canopy-dwelling insects. The decline-induced increase in canopy openness may also modify the understory, shrub and ground layers, and have cascading effects on associated species. Flight interception traps and green Lindgren traps were used to survey the canopy-dwelling insects in stands of healthy and declining oak trees, in particular two insect orders: Raphidioptera, saproxylic insects associated with canopies, and Mecoptera, necrophagous or opportunistic species associated with the herbaceous or shrub strata. Overall, green Lindgren traps caught more of these insects than flight interception traps. The traps caught five species of Raphidioptera. Three of them, Subilla confinis, Phaeostigma major and, to a lesser extent, Phaeostigma notata, were more abundant in stands or plots with declining trees. However, the other two species of Raphidioptera, Atlantoraphidia maculicollis and Xanthostigma xanthostigma exhibited a reverse trend. Two species of Mecoptera, Panorpa germanica and Panorpa communis, were particularly abundant, but unaffected by the level of decline. Our results show that declining forests can either host more or fewer species of Raphidioptera with saproxylic larvae, whereas Mecoptera with ground-living larvae were unaffected. Seasonal phenology and sex ratio of the species are also discussed.

Book review: Dennis R.L.H. 2020: Butterfly biology systems. Connections and interactions in life history and behaviour.Book review

Z. FALTÝNEK FRIC

Eur. J. Entomol. 118: 63, 2021 | DOI: 10.14411/eje.2021.008

Dennis R.L.H. 2020: BUTTERFLY BIOLOGY SYSTEMS. CONNECTIONS AND INTERACTIONS IN LIFE HISTORY AND BEHAVIOUR. CAB International, Wallingford, 504 pp. ISBN 9781789243574. Price GBP 150.00, EUR 180.00, USD 210.00.

Arthropod fauna recorded in flowers of apomictic Taraxacum section RuderaliaOriginal article

Alois HONĚK, Zdenka MARTINKOVÁ, Jiří SKUHROVEC, Miroslav BARTÁK, Jan BEZDĚK, Petr BOGUSCH, Jiří HADRAVA, Jiří HÁJEK, Petr JAN©TA, Josef JELÍNEK, Jan KIRSCHNER, Vítězslav KUBÁŇ, Stano PEKÁR, Pavel PRŮDEK, Pavel ©TYS, Jan ©UMPICH

Eur. J. Entomol. 113: 173-183, 2016 | DOI: 10.14411/eje.2016.021

Flowers of dicotyledonous plants host communities of arthropod species. We studied the community associated with dandelion (Taraxacum section Ruderalia), a complex of apomictic micro-species abundant in central Europe. Identification of microspecies in the field was impracticable. These plants produce an abundance of flowers that host arthropod communities that are not yet fully documented. We investigated species occurrence, its diurnal and seasonal variation and some of the factors that determine the abundance of the dominant species. Insect and spiders were collected from 2010 to 2012 at a locality in Prague. Whole capitula were harvested at weekly intervals and resident arthropods were identified. Diurnal variation in insect presence and the effect of pollen and microclimate on some of the species were also examined. The insect community (> 200 species) consisted mainly of species of Hymenoptera (86 spp.), Coleoptera (56 spp.), Diptera (46 spp.) and Heteroptera (23 spp.). The most abundant were Thysanoptera (2 spp.). Pollen eaters/collectors and nectar feeders dominated over predators and occasional visitors. From April to mid-August, the insect community was dominated by Coleoptera, and later by Diptera and Hymenoptera. Except for Meligethes spp. and species breeding in the capitula, the insects occupied flowers during the daytime when the flowers were open (10-12 h in spring and only 2-4 h in late summer). The presence of Meligethes spp. in particular flowers was associated with the presence of pollen; the occurrence of Byturus ochraceus with pollen and flower temperature. Although pollination is not necessary, dandelion plants produce both nectar and pollen. The community of arthropods that visit dandelion flowers is rich despite their being ephemeral. The composition of local faunas of flower visitors, presence of floral rewards and flower microclimate are important factors determining the composition of the flower community.

Spatial variability in the level of infestation of the leaves of horse chestnut by the horse chestnut leaf miner, Cameraria ohridella (Lepidoptera: Gracillariidae) and in the number of adult moths and parasitoids emerging from leaf litter in an urban environmentOriginal article

Michal KOPAČKA, Rostislav ZEMEK

Eur. J. Entomol. 114: 42-52, 2017 | DOI: 10.14411/eje.2017.007

The horse chestnut leaf miner Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae) was first recorded in Europe near lake Ohrid in the former Yugoslav Republic of Macedonia in 1985 since when it has spread throughout the whole of Europe. The reasons for its spread are well documented. The aim of this study was to assess the population density of the first generation of C. ohridella at eight sites in the urban area of České Budějovice, Czech Republic in two consecutive years. The density was estimated visually in terms of the damage done to horse chestnut leaves by C. ohridella larvae at each site during the vegetative season. The results revealed high variability in the mean percentage of the leaf area damaged ranging from 1.43% to 31.00% and from 0.26% to 23.40% in 2012 and 2013, respectively. The effect of site, year and interaction between these two factors were statistically highly significant. Spatial analysis revealed no autocorrelation in damage among sites indicating that the distribution of C. ohridella is random and not affected by the level of infestation at neighbouring sites. In autumn, samples of leaves were collected and the mortality of diapausing pupae of C. ohridella determined. It ranged from 12.50% to 25.82% and from 10.31% to 22.35% in 2012 and 2013, respectively. There was no significant effect of site and year and their interaction on pupal mortality. The leaf samples were then weighed and put into photo-eclectors, which were placed outdoors. Numbers of adults of C. ohridella and hymenopteran parasitoids that emerged in spring were recorded daily. There were statistically significant associations of the total number of adults that emerged from samples in spring with both site and year as well as their interaction. The number of moths that emerged was positively correlated with the damage done by the first generation of C. ohridella the previous year. Similarly, the total number of parasitoids that emerged was correlated with the number of moths that emerged. The implications of these findings for the optimization of C. ohridella control are discussed.

Comparative cytogenetic analysis in 13 tortoise beetles (Coleoptera: Chrysomelidae: Cassidinae) from BrazilOriginal article

Amália T. LOPES, Flávia R. FERNANDES, Marielle C. SCHNEIDER

Eur. J. Entomol. 113: 352-363, 2016 | DOI: 10.14411/eje.2016.046

In the present work, we have characterized the chromosomes of 13 Cassidinae beetles, belonging to four tribes, the broad aim being to increase the cytogenetic data and establish the mechanisms involved in chromosome evolution of this subfamily, which appear to be conserved karyotypically, i.e. 2n = 16 + Xyp. The analysis of mitotic and meiotic cells revealed a high diversity of diploid numbers (2n = 18, 2n = 22, 2n = 26, 2n = 32, 2n = 36, 2n = 40, 2n = 42), and the presence of sex chromosome system of the Xyp type in most species, with the exception of two representatives that exhibited Xyr and XY systems. C-banding showed constitutive heterochromatin predominantly localized in the pericentromeric region of the chromosomes, but differences regarding the number of chromosomes with positive C-bands, intensity of the blocks, and presence of additional bands in autosomes and/or sex chromosomes were observed among the species investigated. Our data revealed that the karyotype 2n = 16 + Xyp does not occur in all 13 tribes of the Cassidinae characterized cytogenetically, seeming to be only a shared feature among the species of the Cassidini. Variations in the C-band pattern, mainly in closely related species, suggest that the interspecific karyotype diversification occurred as a result of changes in the quantity and distribution of constitutive heterochromatin. The occurrence of the Xyp sex chromosome system in the tribe Mesomphaliini, which showed the highest diversity of simple and multiple systems among the coleopteran as a whole, reinforces the view that derived systems originated by chromosome rearrangements involving the Xyp ancestral system.

Feeding of two species of Scydmaeninae "hole scrapers", Cephennium majus and C. ruthenum (Coleoptera: Staphylinidae), on oribatid mitesOriginal article

Paweł JAŁOSZYŃSKI, Ziemowit OLSZANOWSKI

Eur. J. Entomol. 113: 372-386, 2016 | DOI: 10.14411/eje.2016.048

Prey preferences and feeding-related behaviour of two Central European species of Scydmaeninae, Cephennium majus and Cephennium ruthenum, were studied under laboratory conditions. These beetles capture mites by using unique premental suckers and then penetrate the prey's cuticle by slowly scraping a hole with their short mandibles. A mechanism for interlocking the sides of beetle's labrum with closed mandibles was discovered, confirming that the predator's mouthparts can be tightly sealed around the penetration site, which enables them to inject digestive juices and ingest liquefied tissues of the prey through a tiny hole. The feeding behaviour of Cephennium can be divided into three phases: (i) attack and stabilization of the attachment site (4-5 min); (ii) penetration of the mite's cuticle (ca. 40 min); and (iii) feeding (several hours). Results of prey choice experiments using over 1200 identified mites belonging to 23 families of Oribatida (55 species) and 6 families of Mesostigmata (9 species) demonstrated that C. majus feeds mostly on members of the Oribatida: Phthiracaridae (72.07% of offered phthiracarids, 26.7% of eaten oribatids), Ceratozetidae (100% and 24.7%, respectively), Achipteriidae (95.59% and 21.7%) and Liacaridae (61.97% and 14.7%); C. ruthenum fed mostly on Phthiracaridae (48.68% and 41.6%), Achipteriidae (37.29% and 24.7%) and Ceratozetidae (82.35% and 15.7%). The entire feeding behaviour from attack to completion of feeding in C. majus took 2.00-10.37 h when eating oribatids ranging in body length from 0.34 to 0.70 mm. Interestingly, it took much longer for C. majus to kill ptyctimous Phthiracarus, body length 0.39-0.45 mm, than any non-ptyctimous oribatids, including the much larger (0.64-0.70 mm) Chamobates subglobulus. The two species of Cephennium differed greatly in their preference for eating Liacaridae due to their large size, which was acceptable for the larger C. majus, but at the edge of acceptability for the smaller C. ruthenum. Comparative analysis of mites eaten by all the studied species of Scydmaeninae resulted in a preliminary identification of morphological types of Oribatida acceptable and non-acceptable for ant-like stone beetles. The most readily accepted oribatids are typically subglobose, with a rigid cuticle, smooth or only shallowly and finely microreticulate surface of the idiosoma, covered with sparse setae or nearly asetose and with short or moderately long legs. In contrast, rejected mites have one or a combination of the following characters: body flattened, not subglobose; the cuticle relatively soft; idiosoma deeply sculptured or coarsely reticulate; legs long and spiny; the body covered with a protective crust of soil particles. Crotonioidea, Carabodidae, Damaeidae and Hermanniellidae seem to be particularly well-protected against scydmaenine predators.

What determines the occurrence of fertilized females in hibernating populations of Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae) in Central Europe?Original article

Alois HONĚK, Zdenka MARTINKOVÁ

Eur. J. Entomol. 117: 309-314, 2020 | DOI: 10.14411/eje.2020.036

The current climate warming is associated with the development of a second generation in populations of species such as Pyrrhocoris apterus (L.) (Heteroptera: Pyrrhocoridae), which, in Central Europe, were univoltine in the 1980s. Females of the first generation that develop in spring either enter diapause immediately following the adult moult or after a period of oviposition that gives rise to a second generation. In 2005-2010, in overwintering populations, 3 ± 0.6% of females were fertilized. We explored the possibility that the females that overwintered in a fertilized state were those that had oviposited in the previous season. To test this hypothesis, we reared females of the first generation that moulted to the adult stage in June-August under natural conditions. For these females, we recorded oviposition, mortality and overwintering in the fertilized state. In 2004-2007, the majority (78%) of the first-generation females that oviposited in summer also died before winter and the rest entered dormancy and overwintered. Most of the overwintering females that had laid eggs before overwintering were fertilized. However, the majority (63%) of females that overwintered in the fertilized state had not laid eggs in the previous season; they only copulated and stored the sperm until the next spring. The presence of fertilized females in a hibernating population thus indicates pre-winter sexual activity but not the percentage of first-generation females that oviposit before overwintering.

A review of taxonomy and flower-breeding ecology of the Colocasiomyia toshiokai species group (Diptera: Drosophilidae), with description of a new species from IndonesiaOriginal article

Tao SHI, Masanori J. TODA, Kohei Takenaka TAKANO, Masako YAFUSO, Awit SUWITO, Sin Yeng WONG, Su-Qin SHANG, Jian-Jun GAO

Eur. J. Entomol. 116: 341-361, 2019 | DOI: 10.14411/eje.2019.037

Flies of the Colocasiomyia toshiokai species group depend exclusively on inflorescences/infructescences of the aroid tribe Homalomeneae. The taxonomy and reproductive biology of this group is reviewed on the basis of data and samples collected from Southeast Asia. The species boundaries are determined by combining morphological analyses and molecular species delimitation based on sequences of the mitochondrial COI (cytochrome c oxidase subunit I) gene. For the phylogenetic classification within this species group, a cladistic analysis of all the member species is conducted based on 29 parsimony-informative, morphological characters. As a result, six species are recognised within the toshiokai group, including one new species, viz. C. toshiokai, C. xanthogaster, C. nigricauda, C. erythrocephala, C. heterodonta and C. rostrata sp. n. Various host plants are utilised by these species in different combinations at different localities: Some host plants are monopolized by a single species, while others are shared by two or three species. C. xanthogaster and C. heterodonta cohabit on the same host plant in West Java, breeding on spatially different parts of the spadix. There is a close synchrony between flower-visiting behaviour of flies and flowering events of host plants, which indicate an intimate pollination mutualism.

Asymmetry in host plant preferences of two ecotypes of Boloria eunomia (Lepidoptera: Nymphalidae)Original article

Przemysław KLIMCZUK, Marcin SIELEZNIEW

Eur. J. Entomol. 117: 380-392, 2020 | DOI: 10.14411/eje.2020.042

The diversity and evolution of host-plant relationships of butterflies has been the subject of much research. In this context, an interesting species is the bog fritillary Boloria eunomia. Across its boreo-montane distribution there are several ecotypes of this butterfly (sometimes distinguished as subspecies), which inhabit distinctly different habitats. However, little is known about the relationships between these forms in terms of host-plant use. We compared larval preferences of two ecotypes in north-eastern Poland, a unique region that is inhabited by different evolutionary lineages of B. eunomia. Larvae of the meadow ecotype reared in captivity were able to grow and develop exclusively on Persicaria bistorta, i.e., their 'native' host plant. In contrast, larvae originating from populations inhabiting raised bogs generally showed poorer survival, though they accepted both Ericaceae species growing in their biotope and P. bistorta, a plant that does not occur in their biotope. They did not show clear food preferences, but mortality was lowest when they were fed Vaccinium uliginosum. This is puzzling as field observations indicate that Vaccinium oxycoccus is the main host plant in the area studied. However, our findings are consistent with the results of phylogeographical studies indicating that meadows were the ancestral habitats of B. eunomia and some populations adapted later to different biotopes. The poor survival of larvae of the bog ecotype recorded in the present study may indicate that this form is at least locally potentially more vulnerable than the other ecotype.

Phenotypic pattern over centric fusion clinal variation in the water-hyacinth grasshopper, Cornops aquaticum (Orthoptera: Acrididae)Original article

Pablo C. COLOMBO, María I. REMIS

Eur. J. Entomol. 115: 303-311, 2018 | DOI: 10.14411/eje.2018.029

The water-hyacinth grasshopper, Cornops aquaticum, occurs in freshwater environments in the New World between latitudes 23°N and 35°S. At the southernmost margin of this distribution the populations are polymorphic for three centric fusions (Robertsonian translocations). The frequencies of these chromosome rearrangements increase southwards and the recombination in structural homozygotes and heterozygotes diminishes both along the middle and lower courses of the Paraná River. In the present paper we report a similar cline along the southward flowing Uruguay River. In addition, we report the morphological effects of two of these centric fusion polymorphisms, namely the fusions between chromosomes 2 and 5 of the standard complement (fusion 2/5) and chromosomes 3 and 4 (fusion 3/4) and extend this study to the Uruguay River. There is a strong inverse correlation of fusion frequency with temperature, which indicates that these polymorphisms may be related to increased tolerance of colder climates in this originally tropical species, or some other correlated variable. This study is a further example of chromosomal clines correlated with latitude and is one of a few examples of chromosome polymorphisms associated with phenotypic effects. Finally, it indicates ways of using this species for controlling pests.

Sexual differences in the morphology and movement of a butterfly: Good shape does not make good dispersersOriginal article

Elisabeth REIM, Fee WIDDERICH, Klaus FISCHER

Eur. J. Entomol. 116: 468-476, 2019 | DOI: 10.14411/eje.2019.048

Movements are involved in several routine processes and may scale up to important ecological processes such as dispersal. However, movement is affected by a wealth of factors including flight capacity and behavioural traits. Both frequently differ in the sexes, which may well affect movement. We here aim to disentangle the relative importance of sexual differences in flight capacity versus behaviour on small-scale movements under controlled laboratory conditions in the temperate-zone butterfly Lycaena tityrus. The morphology of males is typically associated with increased flight capacity in this species. Nevertheless, the flight performances of the sexes did not differ, but the mobility of the females was higher. Thus, flight capacity and patterns of movement may not be intimately associated. Rather, the costs and benefits of flight seem to differ substantially between the sexes, with females being more mobile, potentially as a risk spreading strategy, while males are territorial and thus more sedentary. Thus, predictions regarding movement based on morphology are difficult.

Volatile production differs between oak leaves infested by leaf-miner Phyllonorycter harrisella (Lepidoptera: Gracillariidae) and galler Neuroterus quercusbaccarum (Hymenoptera: Cynipidae)Original article

Fabian S. KLIMM, Alexander WEINHOLD, Martin VOLF

Eur. J. Entomol. 117: 101-109, 2020 | DOI: 10.14411/eje.2020.011

Plants defend themselves by producing various volatile organic compounds (VOCs) that have direct and indirect effects on insect herbivores. Their production is often specific to the plant and herbivore species involved, with some herbivores being able to manipulate their production. Here, we used passive volatile sampling using polydimethysiloxane (PDMS) tubing to compare VOCs produced by control, mined and galled oak leaves in the field. Leaves mined by a microlepidopteran leaf-miner (Phyllonorycter harrisella) produced a lower amount of two sesquiterpenes and an increased amount of eucalyptol. In contrast, leaves galled by the gall wasp (Neuroterus quercusbaccarum) did not produce a lower amount of any of the VOC measured when compared to the control. They produced a higher amount of farnesene, β-bourbonene and eucalyptol. Some of these VOC are known for their anti-herbivore function. In a second experiment, we treated the experimental leaves with the phytohormone methyl jasmonate (MeJA) to determine if leaf-miners or gallers reduced the overall inducibility of infested leaves. MeJA induced a sixteen-fold increase in VOC production. However, there was no difference in VOC production of control, mined and galled leaves treated with MeJA. Our results show that up- and down-regulation of VOCs can vary among leaves infested by different herbivores. More experiments are needed to determine if this is due to manipulation by the herbivores themselves or due to a defensive response of the plant.

Laboratory breeding of Korynetes caeruleus (Coleoptera: Cleridae) for the biological control of Anobium punctatum (Coleoptera: Ptinidae)Original article

Tilo HAUSTEIN, Sabine BUSWEILER, Vera HAUSTEIN, Claudia von LAAR, Rudy PLARRE

Eur. J. Entomol. 116: 362-371, 2019 | DOI: 10.14411/eje.2019.038

Larvae and adults of Korynetes caeruleus (de Geer 1775) (Coleoptera: Cleridae) were collected from old churches and reared in the laboratory on Anobium punctatum (de Geer 1774) (Coleoptera: Ptinidae). Breeding success of K. caeruleus was low, but basic parameters of this species' developmental cycle were identified. At 21°C and 75% relative humidity and a four-month cold period at 4°C, the development of K. caeruleus from egg to adult appearance lasted 2 years. The pupal stage may be reached and completed after one and a half years. Feeding on larvae of A. punctatum by larvae of K. caeruleus was observed and consisted of a combination of sucking haemolymph and consuming body parts. The sickle-like mandibles of larvae of K. caeruleus penetrate the cuticle of prey larvae; this is followed by pumping and sucking body movements. Adult beetles of A. punctatum were not attacked by K. caeruleus larvae. Feeding behaviour of adult K. caeruleus was not investigated.

Body weight loss of black soldier fly Hermetia illucens (Diptera: Stratiomyidae) during development in non-feeding stages: Implications for egg clutch parametersOriginal article

Bogdan GEORGESCU, Dănuț STRUȚI, Tudor PĂPUC, Daniela LADOȘI, Anca BOARU

Eur. J. Entomol. 117: 216-225, 2020 | DOI: 10.14411/eje.2020.023

The developmental stages of the black soldier fly, Hermetia illucens, are widely studied because there are several ways in which this species can be utilized. In this context, the aim of the current study is to determine the loss of weight of larvae of different weights between the prepupal and reproductive adult stages and their effect on the egg clutch quality parameters. The Hermetia illucens prepupae were categorized in 3 body weight classes. The weight loss was evaluated by weighing individuals in the prepupal, pupal and adult stages. The weight and length of the individuals were positively correlated in the pupal stage and adult females. There were significant losses of weight (P = 0.000) in the prepupal, pupal and adult stages in all three weight classes. In each weight class the relationship between weights was significant (P = 0.000) for all development stages. The results clearly indicate that the largest larvae of Hermetia illucens produced the adults with the best clutch quality parameters and the existence of significant positive correlations between body weight and both weight loss and the egg clutch quality parameters.

Effect of supplementary nutrition on the reproduction and mating behaviour of Habrobracon hebetor (Hymenoptera: Braconidae)Original article

Yanzhang HUANG, Anqi DAI, Zhenkun MAO, Zhihao CAI, Junqi JIANG

Eur. J. Entomol. 117: 393-399, 2020 | DOI: 10.14411/eje.2020.043

To improve the mass production of the parasitoid Habrobracon hebetor (Say) (Hymenoptera: Braconidae) the effects of supplementary nutrition on its reproduction and mating behaviour were investigated using Plodia interpunctella Hübner (Lepidoptera: Pyralidae) larva as a host. The survival of mated male wasps was markedly prolonged after feeding with five different types of nutrients and that of unmated males was markedly prolonged except when provided with yeast solution. Providing female wasps with supplementary nutrition did not affect their longevity. When H. hebetor reproduced sexually and was supplied with an abundance of hosts, females produced 101.0 and 96.7 female offspring, respectively, when fed 20% sucrose or 20% honey solutions, however, when provided with only ten hosts the provision of supplementary nutrition did not affect the number of female offspring they produced. The 20% maltose, 20% sucrose and 20% honey solutions significantly promoted the courtship behaviour of male wasps, and the 20% yeast and 20% honey solutions increased the mating success of males paired with virgin females.

Tribal affiliation of endemic Macaronesian bush-crickets similar to Tettigonia (Orthoptera: Tettigoniidae) based on their karyology and taxonomyOriginal article

Elżbieta WARCHAŁOWSKA-¦LIWA, Howon RHEE, Klaus-Gerhard HELLER, Beata GRZYWACZ

Eur. J. Entomol. 117: 157-163, 2020 | DOI: 10.14411/eje.2020.018

Two endemic genera of large tettigoniids are found in the Canary Islands and Madeira, which are morphologically similar to the genus Tettigonia. In this study, the karyotypes of representatives of the Glyphonotini genera Calliphona and Psalmatophanes are described for the first time. Comparison of their chromosomes with that of members of Tettigoniini genus Tettigonia revealed that all of the species studied have the same karyotype (2n = 29 with sex determination system X0 in the male), which differs from the ancestral tettigoniid karyotype by one Robertsonian translocation. These results support not only the morphological and molecular genetic evidence but also the hypothesis of a close relationship between Tettigonia and the endemics Calliphona and Psalmatophanes. Cytogenetic data of Glyphonotini strongly indicate that the taxonomy of thes lineage needs to be re-evaluated in which evidence from multiple sources could help resolve the taxonomic problems.

High-diversity microbiomes in the guts of bryophagous beetles (Coleoptera: Byrrhidae)Original article

Petr PYSZKO, Martin ©IGUT, Martin KOSTOVČÍK, Pavel DROZD, Jiří HULCR

Eur. J. Entomol. 116: 432-441, 2019 | DOI: 10.14411/eje.2019.044

The diversity and role of the gut microbiota of insects is a rapidly growing field of entomology, primarily fueled by new metagenomic techniques. Whereas endosymbionts in the guts of xylophagous or herbivorous insects are well studied, the microbiomes in moss-eating (bryophagous) insects remain uncharacterized. Using the Illumina MiSeq platform, we determined the composition of microbiomes in the gut, abdomen and on the body surface of two bryophagous species: Simplocaria semistriata (Fabricius, 1794) and Curimopsis paleata (Erichson, 1846) (Coleoptera: Byrrhidae). Gut microbiomes differed substantially from abdominal microbiomes in the same individuals, which indicates the need to separate them during dissection. Microbiomes in the gut and abdomen differed markedly from surface microbial assemblages. Gut microbiomes in bryophages had the highest MOTU richness, diversity and relative rarity. The eudominant bacteria in the guts and abdomens of bryophages were Novosphingobium, Bradyrhizobium, Ralstonia and Caulobacter, which are responsible for the detoxification of secondary metabolites or nitrogen fixation. These are less common in the surface samples and, therefore, likely to be associated with the specific ability of bryophages to feed on mosses.

Is Isaria fumosorosea selective to Trichogramma pretiosum (Hymenoptera: Trichogrammatidae)?Original article

Michele POTRICH, Gabriela LIBARDONI, Luis F.A. ALVES, Vanda PIETROWSKI, Everton R.L. da SILVA, Pedro M.O.J. NEVES

Eur. J. Entomol. 117: 110-117, 2020 | DOI: 10.14411/eje.2020.012

Entomopathogenic fungi and the egg parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) might be used together in biological control. However, the effects of these fungi on T. pretiosum are not known. Thus, this study aimed to determine the effect of the entomopathogenic fungus Isaria fumosorosea, on the biological parameters of T. pretiosum. Two isolates of I. fumosorosea (IBCB 367 and IBCB 394) were used for this purpose. (1) In a free choice test: cards (1.0 × 5.0 cm) with non-parasitized eggs of Anagasta kuehniella Zeller (Lepidoptera: Pyralidae) were either sprayed with 0.2 mL of the fungus suspension (1.0 × 109 conidia.mL-1) or with sterile distilled water containing Tween® 80 (0.01%), which were then offered to females of T. pretiosum. (2) No choice test: the isolates were sprayed at a concentration of 1.0 × 109 conidia.mL-1 on cards (1.0 × 5.0 cm) with A. kuehniella eggs. The control consisted of spraying sterile distilled water containing Tween® 80 (0.01%). Individual females of T. pretiosum were confined for 24 h with the cards. The number of eggs parasitized, percentage of emergence, longevity, duration of the egg-adult period and sex ratio were evaluated, as well as the longevity of the females that parasitized the eggs and the mortality of the emerging adults evaluated. IBCB 367 isolate repelled T. pretiosum. The pre-parasitism and post-parasitism sprays did not affect the number of eggs parasitized or the sex ratio, however, the pre-parasitism IBCB 394 treatment the females and males survived for longer, whereas the survival of females in post-parasitism treatment with the same isolate was reduced.The presence of conidia on and mycelium of the fungus in T. pretiosum was confirmed using Scanning Electron Microscopy and a histological analysis. Isolates IBCB 367 and IBCB 394 from I. fumosorosea are selective to T. pretiosum in the laboratory.

Diversity of Scarabaeinae (Coleoptera: Scarabaeidae) in an urban fragment of Cerrado in Central BrazilOriginal article

Marina R. FRIZZAS, João L.F.L. BATISTA, Marcus V.C. ROCHA, Charles M. OLIVEIRA

Eur. J. Entomol. 117: 273-281, 2020 | DOI: 10.14411/eje.2020.031

The diversity of dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae) is affected by urbanization, habitat fragmentation and disappearance of native mammals, which result in changes in the quality and availability of food, and resources for nesting. We evaluated the diversity, distribution of species in different trophic guilds and foraging strategies, and temporal variation in abundance of dung beetles in an urban fragment of Cerrado in a Federal District of Brazil. This study was conducted at the Experimental Station of Biology (EEB) of the University of Brasília (UnB), Federal District, Brazil. Fortnightly, between October 2012 and September 2013, Scarabaeinae were collected using baited (human faeces, pig meat, or banana) and unbaited pitfall traps. Aspects of the dung beetle assemblage were evaluated, including species richness and abundance, feeding habits and foraging strategies. A total of 614 individuals were collected, which included eight species belonging to seven genera and four tribes. Dichotomius carbonarius (Mannerheim, 1829), a generalist species, dominated the assemblage, indicating that it is adapted to living in fragmented and urbanized areas. As regards feeding habits, Eurysternus caribaeus (Jablonsky & Herbst, 1789) was considered to be strictly coprophagous, Coprophanaeus cyanescens (d'Olsoufieff, 1924) copronecrophagous and D. carbonarius a generalist. Most species were classified as paracoprids, which accounted for 75% of the species collected. Regarding the attractiveness of the bait, the highest numbers of individuals and species were recorded in pitfall traps baited with human faeces. A high abundance of Scarabaeinae was recorded in the first half of the rainy season (October-December) with 98.2% of the individuals collected in this period. The urban area studied harboured a low number of species with high abundance of a few species.

Identification and expression patterns of chemosensory proteins in the black-back prominent moth, Clostera restitura (Lepidoptera: Notodontidae)Original article

Hui LI, Tianzi GU, Changyu CHEN, Kairu HUANG, Ruixu CHEN, Dejun HAO

Eur. J. Entomol. 116: 372-391, 2019 | DOI: 10.14411/eje.2019.039

Insects have evolved highly specific and sensitive olfactory sensory systems to detect plant hosts and mates. Chemosensory proteins (CSPs) play an important role in this process, but in this respect there is limited information on Clostera restitura, one of the most destructive defoliators of poplars in China. In the present study, we first identified seven candidate CSPs in C. restitura. Sequence alignment and phylogenetic analysis showed that these candidate proteins possessed typical characteristics of the insect CSP family and were similar to those of other Lepidoptera. These genes were expressed in different developmental stages and tissues, and the levels of expression differed after mating. Some CresCSPs were more associated with development and others with mating. They may play an important role in host recognition, egg development and mating behaviour. Furthermore, the CSPs were ubiquitously detected in all tissues and most of them were highly expressed in antennae, especially female antennae. We suggest the CresCSPs may contribute to female oviposition site recognition. CresCSPs that are highly transcribed in wings and legs, may function in gustation. This study provides a better understanding of the molecular mechanisms of olfaction in C. restitura and environmentally friendly pest management strategy for controlling C. restitura.

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