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Results 271 to 300 of 1601:

The role of larval substrate specialization and female oviposition in mediating species diversity of closely-related sepsid flies (Diptera: Sepsidae)Original article

Amelie LAUX, Alexandra WEGMANN, Jeannine ROY, Natalia GOURGOULIANNI, Wolf U. BLANCKENHORN, Patrick T. ROHNER

Eur. J. Entomol. 116: 75-84, 2019 | DOI: 10.14411/eje.2019.008

Coprophagous insect communities play a critical role in the decomposition of vertebrate dung and provide ecosystem functions fundamental to modern agriculture. While the ecology of dung beetles is rather well understood, niche differentiation in coprophagous flies is poorly studied. Sepsid flies (Diptera: Sepsidae) are a vital part of the European community of coprophages, with 6-7 widespread species of Sepsis often found co-occurring in the same pasture. To advance our ecological understanding of the mechanisms that enable species to coexist, we investigated the oviposition preferences and larval performance of 7 common species of Sepsis in the dung of different large domestic and wild mammals. Substrate preferences and subsequent performance of larvae in laboratory experiments did not vary greatly. All species did very well on cow dung, the most common substrate in Central Europe, but also on dung of horse and wild boar. In contrast, flies did not prefer or grow well in dung of red and roe deer, two of the most common wild vertebrates. Thus there were only minor differences among the species tested along the specialist-generalist (dung) gradient, indicating that differences in the choice of oviposition sites by the adults of the different fly species and larval performance do not constitute a major axis of ecological differentiation. Nevertheless, there was a positive correlation between substrate choice and larval performance indicating the preference of gravid females for particular oviposition sites is adaptive. We conclude that sepsids are common in Europe because they are well adapted to the dung of herbivorous livestock rather than wild animals. Nevertheless, specialization on particular types of dung does not define the niche of Sepsis dung flies and hence plays a minor role in mediating their species diversity.

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.

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.

Sibling species delimitation and nomenclature of the Merodon avidus complex (Diptera: Syrphidae)

Dunja POPOVIĆ, Jelena AČANSKI, Mihajla DJAN, Dragana OBREHT, Ante VUJIĆ, Snežana RADENKOVIĆ

Eur. J. Entomol. 112 (4): 790-809, 2015 | DOI: 10.14411/eje.2015.100

A study of the relationships between 21 southern European, Moroccan and Turkish populations of the Merodon avidus species complex was carried out. Based on a parallel study of type material from several museums, documented diagnostic morphological characters, season of adult activity and geographical distribution, we justify the use of the following names for three closely related taxa in this complex: M. avidus (Rossi, 1790), M. moenium (Wiedemann, 1822), and M. ibericus Vujić nom. n. (new name for M. bicolor Gil Collado, 1930, preoccupied by M. bicolor Walker, 1852). Neotypes of Merodon avidus, M. spinipes (Fabricius, 1794) and M. quadrilineatus Lioy, 1864 are designated. Lectotype of Merodon moenium (Wiedemann in Meigen, 1822) is designated here. A cluster analysis of DNA barcoding sequences clearly separated M. ibericus, but not M. avidus and M. moenium, even though the lack of shared haplotypes, analysis of molecular variance (AMOVA), pairwise Φst values together with allozyme and ecological niche analyses revealed statistically significant percentage of variation among all three species in the Merodon avidus complex. Analysis of 5 diagnostic enzyme loci revealed the presence of genetic differentiation among the M. avidus/moenium complex populations investigated (Fst = 0.654) and species-specific alleles were found at the AAT locus. The presence of two separate related taxa within the M. avidus/moenium complex was further supported by an UPGMA tree based on Nei's (1978) genetic distances. The value of Nei's measure of genetic identity (I = 0.520) between two large (meta) populations of M. avidus and M. moenium suggest that these taxa are sibling species. Populations from Djerdap (Serbia) confirmed the presence of temporal divergence between these species at a locality where they occur sympatrically, while spring and autumn populations from Umag (Croatia) provide an example of morphological plasticity within the species M. avidus. Ecological niche analysis contributed to the species delimitation. Review of the available genetic and ecological data confirmed our hypothesis that the M. avidus species complex, in addition to M. ibericus Vujić nom. n. from the Iberian Peninsula, consists of two sibling species in the rest of Europe and indicated their recent speciation.

Fitness traits of Drosophila melanogaster (Diptera: Drosophilidae) after long-term laboratory rearing on different dietsOriginal article

Jelena TRAJKOVIĆ, Vukica VUJIĆ, Dragana MILIČIĆ, Gordana GOJGIĆ-CVIJOVIĆ, Sofija PAVKOVIĆ-LUČIĆ, Tatjana SAVIĆ

Eur. J. Entomol. 114: 222-229, 2017 | DOI: 10.14411/eje.2017.027

Nutrition is one of the most important environmental factors that influence the development and growth in Drosophila. The food composition strongly affects their reproduction, welfare and survival, so it is necessary for flies to search for a mixture of macronutrients that maximizes their fitness. We have five D. melanogaster strains, which were reared for 13 years on five different substrates: standard cornmeal-agar-sugar-yeast medium and four substrates modified by adding tomato, banana, carrot and apple. This study was aimed at determining how such long-term rearing of flies on substrates with different protein content affects fitness traits (dynamics of eclosion, developmental time and egg-to-adult survival). Further, we determined how transferring flies reared on fruit/vegetable substrates to a standard laboratory diet affected their fitness. Results indicate that strains reared on the diet with the lowest content of protein and the highest C/N ratio had the slowest eclosion and developmental time, and lowest egg-to-adult survival (apple diet). The flies reared on the diet with the highest protein content and the lowest C/N ratio had the highest survival (tomato diet). Flies reared on the carrot diet, which is quite similar in protein content and C/N ratio to the standard cornmeal diet, had the fastest development. Transferring flies to the standard cornmeal diet accelerate eclosion and developmental time, but did not affect survival.

Overwintering of ladybirds (Coleoptera: Coccinellidae) on Scots pine in Central EuropeOriginal article

Milada HOLECOVÁ, Peter ZACH, Katarína HOLLÁ, Miroslava ŠEBESTOVÁ, Mária KLESNIAKOVÁ, Anna ŠESTÁKOVÁ, Alois HONĚK, Oldřich NEDVĚD, Michal PARÁK, Zdenka MARTINKOVÁ, Juraj HOLEC, Sandra VIGLÁŠOVÁ, Peter M.J. BROWN, Helen E. ROY, Ján KULFAN

Eur. J. Entomol. 115: 658-667, 2018 | DOI: 10.14411/eje.2018.065

We surveyed ladybirds (Coleoptera: Coccinellidae) in 10 stands of Scots pine (Pinus sylvestris), all monoculture stands 5-100 years old, in western Slovakia, Central Europe, over two successive periods, October 2013 - March 2014 and October 2014 - March 2015. The winter in each period was exceptionally mild. Ladybirds were collected from the lower branches of pine trees using beating trays and were present in 61% of the 1040 samples (one sample containing ladybirds from 20 branches, 1 m long each). In total 3965 individuals of 20 species were recorded. Non-conifer dwelling species associated with broadleaved trees or herbaceous plants prevailed (45% of species), followed by conifer specialists (40%) and generalists (15%). Although 13 species were found at least in one winter month, December, January or February, only four of them, Exochomus quadripustulatus, Coccinella septempunctata, Harmonia axyridis and Hippodamia variegata, were recorded continually during both winters. The number of species, the abundance of all ladybirds and the abundance of dominant species (E. quadripustulatus, C. septempunctata and H. axyridis) decreased from late autumn towards winter and remained lowest during this most adverse time of the year for ladybirds. Overwintering species assemblages of ladybirds changed over time and varied with age of pine stand. Our results suggest that Scots pine in Central Europe supports species rich assemblages of ladybirds from late autumn to early spring and, being widely distributed, it could be suited to winter surveying of ladybirds at large spatial scales to reveal behavioural and ecological responses of species to changing weather or different climates.

An early suitability assessment of two exotic Ophraella species (Coleoptera: Chrysomelidae) for biological control of invasive ragweed in EuropeOriginal article

Suzanne T.E. LOMMEN, Emilien F. JOLIDON, Yan SUN, José I. BUSTAMANTE EDUARDO, Heinz MÜLLER-SCHÄRER

Eur. J. Entomol. 114: 160-169, 2017 | DOI: 10.14411/eje.2017.021

Classical biological control is an important means of managing the increasing threat of invasive plants. It constitutes the introduction of natural enemies from the native range of the target plant into the invaded area. This method may be the only cost-effective solution to control the rapidly expanding common ragweed, Ambrosia artemisiifolia, in non-crop habitats in Europe. Therefore, candidate biocontrol agents urgently need to be assessed for their suitability for ragweed control in Europe. A previous literature review prioritized the host-specific leaf beetle Ophraella slobodkini as a candidate agent for ragweed control in Europe, whereas it rejected its oligophagous congener O. communa. Meanwhile, O. communa was accidentally introduced and became established south of the European Alps, and we show here that it is expanding its European range. We then present a short version of the traditional pre-release risk-benefit assessment for these two candidate agents to facilitate fast decision-making about further research efforts. We selected two complementary tests that can be conducted relatively rapidly and inform about essential risks and benefits. We conducted a comparative no-choice juvenile performance assay using leaves of ragweed and sunflower, the most important non-target plant, in Petri dishes in climatic conditions similar to that in the current European range of O. communa. This informs on the fundamental host range and potential for increasing abundance on these host plants. The results confirm that O. slobodkini does not survive on, and is hence unlikely to cause severe damage to sunflower, while O. communa can survive but develops more slowly on sunflower than on ragweed. In parallel, our species distribution models predict no suitable area for the establishment of O. slobodkini in Europe, while O. communa is likely to expand its current range to include a maximum of 18% of the European ragweed distribution. Based on this early assessment, the prioritization and further assessment of O. slobodkini seem unwarranted whereas the results urgently advocate further risk-benefit analysis of O. communa. Having revealed that most of the European area colonized by ragweed is unlikely to be suitable for these species of Ophraella we suggest the use of such relatively short and cheap preliminary assessment to prioritise other candidate agents or strains for these areas.

Discovery of a remarkable new species of Lymanopoda (Lepidoptera: Nymphalidae: Satyrinae) and considerations of its phylogenetic position: An integrative taxonomic approachOriginal article

Tomasz W. PYRCZ, Carlos PRIETO, Pierre BOYER, Jadwiga LORENC-BRUDECKA

Eur. J. Entomol. 115: 387-399, 2018 | DOI: 10.14411/eje.2018.039

A new species of Lymanopoda Westwood, a cloud forest Neotropical genus of Satyrinae, is described from the páramo grasslands on an isolated, peripheral massif in the Colombian Central Cordillera of the Andes: L. flammigera Pyrcz, Prieto & Boyer, sp. n. The genus Lymanopoda is species-rich (approx. 65 species) and its alpha taxonomy is relatively well researched. Relationships within the genus using molecular data have also been explored. The new species is outstanding for its golden yellow colour in males, not found in any other neotropical Satyrinae. Cladograms were constructed based on COI sequences of 47 species of Lymanopoda (~ 70% of the known species) including 17 from Colombia. The new species segregates in the "tolima" clade, which comprises four other high altitude Colombian species, as well as two from Ecuador. However, it is the comparative analysis of male genitalia, in particular the superuncus and valvae, which identified its closest relatives, thus confirming that genital characters can help refine molecular phylogenies. In addition to identifying species using mitochondrial DNA (mtDNA barcodes), nucleotide sites with unique fixed states used to identify nine species of Lymanopoda from Colombia are also presented.

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.

Detailed morphological descriptions of the immature stages of the ant parasite Microdon mutabilis (Diptera: Syrphidae: Microdontinae) and a discussion of its functional morphology, behaviour and host specificityOriginal article

Giulia SCARPARO, Pierfilippo CERRETTI, Maurizio MEI, Andrea DI GIULIO

Eur. J. Entomol. 114: 565-586, 2017 | DOI: 10.14411/eje.2017.071

The myrmecophilous immature stages of hover flies of the genus Microdon Meigen, 1803 (Diptera, Syrphidae) are still poorly known and only about 15 species were previously incompletely described and/or illustrated using light microscopy based on occasional findings mainly of pupae and third instar larvae. The exceptional finding of a large number of second and third instar larvae and pupae (159 specimens) of Microdon mutabilis (Linnaeus, 1758) inside the nest of a new host species, Formica cunicularia Latreille,1798, enabled us to rear them and obtain a great number of eggs and first instar larvae. We filmed and described the feeding behaviour and locomotion of these highly derived slug-like larvae. Combining light, fluorescence and scanning electron (SEM) microscopy, we describe in detail and illustrate the external features of all the immature stages of M. mutabilis (eggs, larvae and pupae). Covering the entire chorion of the egg is a peculiar microsculpture composed of volcano-like processes. The three larval instars strongly differ from each other, especially at the level of the shape of the body, the posterior spiracular tubercle and the cephaloskeleton. SEM microscopy was used to describe in detail the microsculpture, sensorial structures, spiracles and cephalic appendages of larvae and pupae. Fluorescence microscopy was used to reveal the exceptional presence of resilin in the external layer of the posterior spiracular tubercle in first instar larvae. The possible functional significance of these structures is discussed.

Influence of a diet containing tobacco on the biology of Ephestia kuehniella (Lepidoptera: Pyralidae) and its parasitoid Habrobracon hebetor (Hymenoptera: Braconidae)Original article

Cleder PEZZINI, Simone MUNDSTOCK JAHNKE, Andreas KÖHLER

Eur. J. Entomol. 117: 190-198, 2020 | DOI: 10.14411/eje.2020.020

Host diet often influences its biological parameters and the success of their parasitoids, both in mass rearing, field research and parasitism in applied biological control programs. Habrobracon hebetor (Say, 1836) (Hymenoptera: Braconidae) is an important biological control agent of the flour moth Ephestia kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae), which infests tobacco, grain and other products in storage. This study aimed to evaluate the effect of different proportions of tobacco in artificial diets on the biological parameters of the host E. kuehniella and its parasitoid H. hebetor. Four classes of Virginia tobacco with different sugar and nicotine concentrations were added to flour diets for moths in different percentages (5, 10 and 15%).The experimental design was completely randomized in a 3 × 4 factorial scheme (percentage of dietary tobacco × class of tobacco). In the parasitoid bioassays, hosts fed only with 5% tobacco were used. For E. kuehniella, the development time (egg-adult), viability of immature stages, sex ratio, fecundity, egg viability and longevity were measured. For H. hebetor, percentage parasitism, offspring sex ratio, number of paralyzed and parasitized larvae, egg-adult viability and parasitism preference were measured. Tobacco classes and percentages added to the diet influenced the development time and viability of E. kuehniella. The 5% host diet did not influence the different biological parameters and behaviour of H. hebetor. For mass rearing of H. hebetor, it is unnecessary to add tobacco to the artificial diet in order to improve parasitoid performance.

Fungi associated with Ips acuminatus (Coleoptera: Curculionidae) in Ukraine with a special emphasis on pathogenicity of ophiostomatoid speciesOriginal article

Kateryna DAVYDENKO, Rimvydas VASAITIS, Audrius MENKIS

Eur. J. Entomol. 114: 77-85, 2017 | DOI: 10.14411/eje.2017.011

Conifer bark beetles are well known to be associated with fungal complexes, which consist of pathogenic ophiostomatoid fungi as well as obligate saprotroph species. However, there is little information on fungi associated with Ips acuminatus in central and eastern Europe. The aim of the study was to investigate the composition of the fungal communities associated with the pine engraver beetle, I. acuminatus, in the forest-steppe zone in Ukraine and to evaluate the pathogenicity of six associated ophiostomatoid species by inoculating three-year-old Scots pine seedlings with these fungi. In total, 384 adult beetles were collected from under the bark of declining and dead Scots pine trees at two different sites. Fungal culturing from 192 beetles resulted in 447 cultures and direct sequencing of ITS rRNA from 192 beetles in 496 high-quality sequences. Identification of the above revealed that the overall fungal community was composed of 60 species. Among these, the most common were Entomocorticium sp. (24.5%), Diplodia pinea (24.0%), Ophiostoma ips (16.7%), Sydowia polyspora (15.1%), Graphilbum cf rectangulosporium (15.1%), Ophiostoma minus (13.8%) and Cladosporium pini-ponderosae (13.0%). Pathogenicity tests were done using six species of ophiostomatoid fungi, which were inoculated into Scots pine seedlings. All ophiostomatoid fungi tested successfully infected seedlings of Scots pine with varying degrees of virulence. Ophiostoma minus was the only fungus that caused dieback in inoculated seedlings. It is concluded that I. acuminatus vectors a species-rich fungal community including pathogens such as D. pinea and O. minus. The fungal community reported in the present study is different from that reported in other regions of Europe. Pathogenicity tests showed that O. minus was the most virulent causing dieback in seedlings of Scots pine, while other fungi tested appeared to be only slightly pathogenic or completely non-pathogenic.

The year-round phenology of the migratory Red Admiral Vanessa atalanta (Lepidoptera: Nymphalidae) in a Mediterranean area in southern SpainOriginal article

Mariano CUADRADO

Eur. J. Entomol. 114: 517-525, 2017 | DOI: 10.14411/eje.2017.066

Many studies report the migratory status of Vanessa atalanta in the Palearctic. Available evidence indicates that this species migrates north in spring to reproduce and south in autumn to reproduce in the Mediterranean area. However, little is known about the year-round phenology and their overwintering in southern regions. Here, I present data on the year-round phenology of adult V. atalanta recorded during a three year period (2014-2016) at 5 lowland sites (< 80 m a.s.l.) near the coast close to Cádiz (southern Spain). Overall, a total of 826 imagoes were recorded along 1499.3 km of Butterfly Monitoring Scheme (BMS) transects. Abundance was 0.55 butterflies/km (data for all sites and years pooled) and varied greatly among sites and years. Coinciding with the migratory status, imagoes were recorded from September to June each year and the year-round abundance showed a typical bimodal distribution with two peaks of abundance, one in late winter (February) and another in autumn (November). Abundance was higher in spring (0.87 butterflies/km) than in autumn (0.60 butterflies/km). The emergence of a local generation in late winter was also recorded. My results agree with the migratory phenology of this species in the Palearctic and support the year round phenology data reported by Stefanescu (2001).

Unusual chromosome polymorphism and heterochromatin variation in the Argentinean population of the necrophagous fly Lucilia sericata (Diptera: Calliphoridae), comparison with other populations and evolutionary aspectsOriginal article

Mónica Gabriela CHIRINO, María Florencia FOURASTIE, Néstor Daniel CENTENO, María José BRESSA

Eur. J. Entomol. 117: 295-301, 2020 | DOI: 10.14411/eje.2020.034

Heterochromatin may vary qualitatively, quantitatively, and in its location both in and between species. There were differences recorded in sex chromosomes, satellite sizes and location of C-bands in specimens of Lucilia sericata (Meigen, 1826) from three localities in the Buenos Aires region, Argentina (Bernal, Castelar, and Buenos Aires City). Mitotic analyses revealed the same diploid chromosome number of 2n = 10 + XY / XX (male / female) and the same size, morphology, and C-banding patterns on their autosomes. However, there are different morphotypes of X and Y chromosomes with a distinctive heterochromatin content in both arms. Four morphotypes of X (X1, X2, X3, and X4) and three of Y (Y1, Y2, and Y3) were recorded. The X metacentric and Y subtelocentric chromosomes were identified based on their very large and small sizes, respectively, and both had large heterochromatic blocks. These intraspecific differences are mainly due to quantitative variations in non-coding repetitive sequences located in the arms of both X and Y sex chromosomes. The specimens were very polymorphic both between and within the three localities sampled. Cytogenetic studies on specimens of L. sericata from the Nearctic, Palaearctic and Ethiopian regions also report differences in the morphology of the sex chromosomes and their C-banding patterns, some of which may have evolved independently. Our cytogenetic observations on L. sericata indicate that the accumulation of heterochromatin in the genome could be involved in chromosomal divergence and karyotype evolution of this species, as demonstrated in other Diptera. The polymorphic sex chromosomes are therefore important for understanding the evolution within species as well as speciation.

Cannibalism among same-aged nymphs of the omnivorous predator Dicyphus errans (Hemiptera: Miridae) is affected by food availability and nymphal densityOriginal article

Konstantina ARVANITI, Argyro FANTINOU, Dionyssios PERDIKIS

Eur. J. Entomol. 116: 302-308, 2019 | DOI: 10.14411/eje.2019.033

Cannibalism, the act of eating an individual of the same species has been little studied in omnivorous insect predators. Dicyphus errans (Wolff) (Hemiptera: Miridae) is a generalist omnivorous predator that commonly occurs in tomato greenhouses and field crops in the Mediterranean basin. In this work cannibalism among same-aged neonate nymphs of D. errans was studied when 1, 2, 4, 8 or 16 individuals were placed in a Petri dish along with or without heterospecific prey. Although nymphs were unable to complete their development in the absence of prey they survived longer when there were initially 2 individuals per dish than in any other treatment including a single individual. This may indicate that cannibalism in this predator has positive effect on nymphal survival, which however was not the case at higher densities. The presence of heterospecific prey increased nymphal survival and individuals were as equally successful in completing their development as when kept singly. Developmental time in all the treatments was very similar. Adult weight of both females and males was significantly greater when a nymph was reared alone and similar in all the other treatments. The results indicate that cannibalism occurs among neonates of D. errans if heterospecific prey is scarce and has a negative effect on adult weight when heterospecific prey is abundant. This should be considered in studies on enhancing the biocontrol efficiency or mass rearing of this predator.

Chenicoris dilatatus, a remarkable new genus and new species of assassin bug (Hemiptera: Heteroptera: Reduviidae: Harpactorinae) from southern ChinaOriginal article

Zhuo CHEN, Jianyun WANG, Hu LI, Wanzhi CAI

Eur. J. Entomol. 117: 252-259, 2020 | DOI: 10.14411/eje.2020.027

Chenicoris dilatatus gen. n. & sp. n. from southern China is described and placed in the largest assassin bug subfamily Harpactorinae (Hemiptera: Heteroptera: Reduviidae). The new species is similar to members of Isyndus Stål, 1859 in general habitus, but can be distinguished from the latter by the unarmed anterior pronotal lobe, the laterally dilated lobe-like abdominal segment V and several features of its genitalia.

Tendency and consequences of superparasitism for the parasitoid Ooencyrtus pityocampae (Hymenoptera: Encyrtidae) in parasitizing a new laboratory host, Philosamia ricini (Lepidoptera: Saturniidae)Original article

Hilal TUNCA, Maurane BURADINO, Etty-Ambre COLOMBEL, Elisabeth TABONE

Eur. J. Entomol. 113: 51-59, 2016 | DOI: 10.14411/eje.2016.006

The tendency for self-superparasitism and it's effects on the quality of the parasitoid Ooencyrtus pityocampae (Mercet) (Hymenoptera: Encyrtidae) in parasitizing a new laboratory host, Philosamia ricini (Danovan) (Lepidoptera: Saturniidae), were investigated. In this study, female parasitoids of various ages (1-, 3- and 5-day-old) were tested individually. Parasitoids were provided with 1-day-old P. ricini eggs at ratios of 5, 10, 20, 30 and 40 host eggs per wasp. The tendency to superparasitize was dependent on the female's age and host density. Five-day-old females showed a strong tendency to superparasitize at low host densities. The development time of wasps in superparasitized eggs was longer than that of wasps in singly parasitized eggs. The size and longevity of adult parasitoids decreased significantly with superparasitism. This work contributes to the development of an efficient mass rearing and laboratory rearing of the parasitoid O. pityocampae using a new host.

Two new species and one new record for the genus Copris (Coleoptera: Scarabaeidae: Scarabaeinae) from Vietnam with a key to Vietnamese speciesOriginal article

Van Bac BUI, Kenneth DUMACK, Michael BONKOWSKI

Eur. J. Entomol. 115: 167-191, 2018 | DOI: 10.14411/eje.2018.016

Two new species of Copris Geoffroy, 1762 are described and illustrated: Copris (subgenus incertae sedis) caobangensis sp. n. from Caobang Province (northern Vietnam) and Copris (Copris) sonensis sp. n. from Thanhhoa Province (central Vietnam). Copris (Copris) szechouanicus Balthasar, 1958 is recorded in Vietnam for the first time and data on the morphology, distribution and ecology of this species are given. An updated species list and an identification key for the Copris species so far known from Vietnam are presented along with detailed photographs of the poorly known species.

One step closer to understanding the ecology of Cameraria ohridella (Lepidoptera: Gracillariidae): The effects of light conditionsOriginal article

Radosław JAGIEŁŁO, Edward BARANIAK, Marzenna GUZICKA, Piotr KAROLEWSKI, Adrian ŁUKOWSKI, Marian Jędrzej GIERTYCH

Eur. J. Entomol. 116: 42-51, 2019 | DOI: 10.14411/eje.2019.005

Horse chestnut leaf miner (Cameraria ohridella) has achieved ecological success by colonizing the entire European range of its primary host, horse chestnut (Aesculus hippocastanum). This insect has attracted the attention of scientists, but its ecology is poorly understood. Here, we investigated the effects of varying degrees of light availability on the leaf morphology of horse chestnut saplings and the performance of C. ohridella. A pot experiment under greenhouse conditions was performed in which the photosynthetic photon flux density (PPFD) was reduced from full light by 50% (high light - HL) or 80% (low light - LL). Insect performance parameters were quantified (i.e., pupal mass, efficiency of conversion of utilised leaf tissue (ECU) and potential fecundity). Compared with HL leaflets those from LL were characterised by higher contents of nitrogen and water but lower total phenolics. The oxidative capacity of phenolics (at pH ≈ 10, common in the lepidopteran gut) was low and did not differ in the two treatments. Compared with those collected from HL leaves, the mines of those collected from leaves of plants grown under LL conditions were larger in area but the leaf mass utilized by larvae was similar. Pupae were heavier in LL than in HL conditions, and ECU was higher in LL. The potential fecundity of females was not sensitive for experimental treatment. We conclude that (1) reduced light had a strong beneficial effect on the performance of C. ohridella and (2) phenolics in A. hippocastanum leaf tissues are a poor defence against this herbivore.

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

Petr PYSZKO, Martin ŠIGUT, 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.

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.

Comparison of growth parameters of the predator, Chrysoperla nipponensis-B (Neuroptera: Chrysopidae) reared on a diet of eggs of Corcyra cephalonica (Lepidoptera: Pyralidae) and an artificial diet containing gingerOriginal article

Shafique A. MEMON, Dzolkhifli OMAR, Rita MUHAMAD, Ahamd S. SAJAP, Norhayu ASIB, Arfan A. GILAL

Eur. J. Entomol. 113: 387-392, 2016 | DOI: 10.14411/eje.2016.049

The growth parameters of the green lacewing, Chrysoperla nipponensis-B (Okamoto), were studied under laboratory conditions. The highest mortality was recorded in the immature stages (instars 1st, 2nd, 3rd and pupae) of C. nipponensis fed on the eggs of Corcyra cephalonica (37.26%). The sex ratios (proportion of female to male) when reared on the eggs of C. cephalonica and an artificial diet with ginger were 0.93 : 1.00 and 0.87 : 1.00, respectively. The maximum life spans of females reared on the eggs of C. cephalonica and an artificial diet with ginger were 63 and 64 days, respectively. The females reared on the eggs of C. cephalonica produced the highest number of eggs (10.4) on the fifth day of oviposition, whereas on the artificial diet with ginger it was 9.26 on the eighth day of oviposition. The net reproductive rate (Ro) and maximum gross reproductive rate (GRR) of C. nipponensis fed on the eggs of C. cephalonica were 69.50 and 223.10 females per female per generation, respectively, whereas for the artificial diet with ginger they were 117.24 and 236.89 females per female per generation, respectively. Mean generation time (T) was 37.06 and 48.16 for the eggs of C. cephalonica and artificial diet with ginger, respectively. The intrinsic rate of natural increase (r) was 0.11 and 0.09 females per female per day for the eggs of C. cephalonica and artificial diet with ginger, respectively. The finite rate of increase (λ) was 1.12 and 1.11 females per female per day for the eggs of C. cephalonica and artificial diet with ginger, respectively. The population doubling time (DT) was 6.05 days on the diet of eggs of C. cephalonica and 7.00 on the artificial diet with ginger.

Bactrocera oleae (Diptera: Tephritidae) organophosphate resistance alleles in Iberia: Recent expansion and variable frequencies

Isabel PEREIRA-CASTRO, Barbara VAN ASCH, Fernando TRINDADE REI, Luís TEIXEIRA DA COSTA

Eur. J. Entomol. 112 (1): 20-26, 2015 | DOI: 10.14411/eje.2015.019

The olive fly, Bactrocera oleae (Rossi, 1790) (Diptera: Tephritidae), is the most important pest of olive trees globally, causing losses that, in the absence of control measures, can exceed 90% of the crop. In the Mediterranean basin, where the overwhelming majority of production is concentrated (~ 98%), organophosphate insecticides (OPs) have been the main tool for B. oleae control for the last four decades, leading to the development of resistance to these compounds. Mutations of the Ace gene, which codes for acetylcholinesterase, the target enzyme of OPs and other insecticides, have been identified as the underlying cause, with studies reporting mid to very high frequencies of resistance alleles in several countries. Interestingly, no resistance alleles were detected in Portugal, at the Western end of the Mediterranean basin. As the original study was done almost a decade ago and did not include many samples, we decided to re-evaluate the situation, by analysing a larger number of individuals from multiple locations in Western and Southern Iberia (Portugal and Spain). In our present study, resistance-associated Ace alleles were found to have become widespread in both regions, but with highly varying frequencies. Together with the observed haplotype distributions, this finding is consistent with previous suggestions of a recent, selection-driven spread and has implications for the importance of Ace mutations in organophosphate resistance in the field as well as the importance of gene flow between Mediterranean populations of B. oleae.

Long-term partitioning of space between two territorial species of ants (Hymenoptera: Formicidae) and their effect on subordinate species

Wojciech CZECHOWSKI, Bálint MARKÓ, Alexander RADCHENKO, Piotr ŚLIPIŃSKI

Eur. J. Entomol. 110 (2): 327-337, 2013 | DOI: 10.14411/eje.2013.046

Competition is a major force organizing ant communities and results in co-occurring species evolving different strategies for foraging and use of space. Territorial species, as top dominants exclude each other, while shaping the local ant communities both qualitatively and quantitatively. In this study we examined how two territorial species, Formica polyctena and Lasius fuliginosus, can coexist in adjacent territories over long periods of time, and whether they affect co-occurring species of ants in different ways. Field observations in the absence and in the presence of baits were carried out around a L. fuliginosus nest complex surrounded by a polydomous F. polyctena colony in S Finland in 2007-2009. Both species controlled their territories, but were affected by changes in the abundance of the other species and the distance from L. fuliginosus' main nest. They did not have the same effect on the subordinate species in the absence of baits, but the abundance of Myrmica spp. recorded at baits was negatively affected by both of the territorial species. The preferences of the different species for the artificial food sources differed: L. fuliginosus and F. polyctena preferred tuna to honey and Myrmica spp. honey to tuna. More individuals of the subordinate species were recorded in the territory of F. polyctena than of L. fuliginosus, although conflicts with this territorial species were also recorded. During the three years of the study almost no overlaps in the territories of the two territorial species were recorded, and there were mostly minor shifts in the boundaries of the territories. Differences between the two territorial species in their use of space and competitive effects ensured their coexistence at this particular site in Finland.

Demographic parameters of Diuraphis noxia (Hemiptera: Aphididae) and Hippodamia variegata (Coleoptera: Coccinellidae) recorded in the context of D. noxia infesting resistant and susceptible cultivars of wheat

Leila ZANGANEH, Hossein MADADI, Hossein ALLAHYARI

Eur. J. Entomol. 112 (3): 453-459, 2015 | DOI: 10.14411/eje.2015.053

The Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), is a serious pest of small grains and can cause losses of about 80% in wheat yields. Chemical control is ineffective against this pest so the combined use of host plant resistance and biological control is seen as a possible better means of controlling this pest. In this study, the potential effect of Omid (resistant) and Sardari (susceptible) cultivars of wheat on life table parameters and daily fecundity of RWA and its predator, Hippodamia variegata (Goeze), were determined using the age-stage two-sex life table theory. The results indicate that the rm, R0, λ, T and GRR of RWA were -0.005 ± 0.01 day-1, 0.9 ± 0.24 offspring per individual, 0.99 ± 0.01 day-1, 21.16 ± 1.79 days and 13.34 ± 2.91 offspring on Omid and 0.159 ± 0.01 day-1, 6.9 ± 0.54 offspring per individual, 1.17 ± 0.01 day-1, 12.14 ± 0.26 days and 12.73 ± 1.22 offspring on Sardari. The corresponding values for H. variegata fed on RWA reared on Omid were 0.24 ± 0.01 day-1, 399.35 ± 53.01 eggs, 1.27 ± 0.01 day-1, 24.67 ± 0.28 days and 544.23 ± 75.86 eggs and on Sardari 0.20 ± 0.006 day-1, 221.56 ± 34.68 eggs, 1.23 ± 0.01 day-1, 26.50 ± 0.41 days and 402.72 ± 67.55, respectively. The resistance of wheat cultivars significantly affected life table parameters and mean fecundity of RWA and H. variegata. Our results indicate that combining both host plant resistance and predators in the integrated pest management of RWA could result in a synergistic effect.

Evidence of forage distance limitations for small bees (Hymenoptera: Apidae)

Ivan R. WRIGHT, Stuart P.M. ROBERTS, Bonnie E. COLLINS

Eur. J. Entomol. 112 (2): 303-310, 2015 | DOI: 10.14411/eje.2015.028

The distribution of ground-nesting bees was investigated using transects of water traps in a mosaic of nesting and forage habitats at Shotover Hill in Oxfordshire, UK. The site includes a large area of ground-nesting bee activity and is adjoined on three sides by floristic hay meadows. This study showed that the females of small bee species (< 1.5 mm intertegular span) that were foraging in the hay meadows demonstrated a functional limitation to their homing range. The abundance of small bees declined rapidly with increasing distance from areas of high density nesting; declining more rapidly than might be expected from uniform dispersal into the surrounding landscape. By modelling the occurrence of bees along each transect it was found that the probability of observing a small bee in the hay meadows was reduced to 10% at a distance of 250-370 m from the nesting habitat. The result emphasises the scale on which habitat fragmentation will begin to impact upon bee diversity, and the relative contribution of managed "pollen and nectar" strips to areas of nesting habitat.

Is the type of soil an important factor determining the local abundance of carrion beetles (Coleoptera: Silphidae)?

Pavel JAKUBEC, Jan RŮŽIČKA

Eur. J. Entomol. 112 (4): 747-754, 2015 | DOI: 10.14411/eje.2015.071

Carrion beetles (Coleoptera: Silphidae) provide a valuable ecosystem service by promoting nutrient cycling and controlling pests like noxious flies (Diptera: Calliphoridae and Sarcophagidae). Our main goal was to examine the relationship between the occurrence of carrion beetles and soil type. We used pitfall traps to collect 43,856 specimens of 15 species of carrion beetles in the Czech Republic during 2009. We found that the abundance of seven of the carrion beetles - Nicrophorus antennatus (Reitter), N. germanicus (Linnaeus), N. humator (Gleditsch), N. interruptus (Stephens), N. sepultor (Charpentier), Silpha obscura obscura (Herbst) and T. sinuatus (Fabricius) - was significantly higher either in areas with chernozem or fluvisol soils. These findings support our hypothesis that soil type could be an important factor determining the occurrence of necrophagous European carrion beetles. Our findings could be helpful when selecting important nature conservation sites (particularly inasmuch as N. antennatus, N. germanicus and N. sepultor are listed as endangered species on the Czech Red List of Invertebrates) as in this respect localities where there are chernozem soils are potentially valuable.

Correlations between landscape attributes and ecological traits of Lepidoptera communities in olive groves

Stefano SCALERCIO, Pietro BRANDMAYR, Nino IANNOTTA, Ruggero PETACCHI, Luigi BOCCACCIO

Eur. J. Entomol. 109 (2): 207-216, 2012 | DOI: 10.14411/eje.2012.027

The effects of landscape attributes on Lepidoptera communities were studied in an agricultural area in Calabria (S-Italy). The association between a set of community descriptors and landscape metrics was determined using a multi-scale approach. Lepidoptera were sampled using yellow sticky traps in 10 olive groves. The landscape in 5 concentric areas, with radii from 250 to 1250 m, around each sampling site was analyzed. The composition and configuration of the landscape were calculated both at the landscape and class level based on the main classes of land use. The following life-history traits of Lepidoptera were considered: (i) dispersal ability of adults, (ii) habitat preferences and (iii) diet breadth of larvae. An index of community vulnerability was calculated by combining life-history traits and species diversity. There were no significant correlations between any of the landscape metrics and species richness or between species richness and abundance of natural or semi-natural habitats. However, life-history traits were significantly correlated with some landscape metrics, depending on the spatial scale. Most notably, landscape diversity is positively correlated with community vulnerability. The presence of sensitive species in olive orchards, but not species richness per se, is associated with the presence of natural and semi-natural habitats in the surrounding agricultural landscape. In conclusion, responses of communities to landscape changes are more likely to be revealed by an analysis of ecological traits, than species richness. In particular, the vulnerability index, used in this joint analysis of the main ecological traits, seems to be an effective descriptor of the relationships between communities and landscape.

Diversity of adipokinetic hormones in termites (Isoptera)Original article

Veronika JEDLIČKOVÁ, Pavel JEDLIČKA, Barbora ŠPULÁKOVÁ

Eur. J. Entomol. 113: 364-371, 2016 | DOI: 10.14411/eje.2016.047

In this study we report on the structural diversity of adipokinetic hormones (AKHs) in the evolutionarily oldest group of social insects, the termites (Isoptera). Using molecular methods combined with in silico bioinformatic analysis, we studied and compared the sequences coding for these neuropeptides in thirteen species of five families of Isoptera. There are three types of AKH octapeptides in termites: Empusa pennata adipokinetic hormone (Emppe-AKH; pQVNFTPNWamide), Microhodotermes viator corpus cardiacum peptide (Micvi-CC; pQINFTPNWamide) and Periplaneta americana cardioaccelerating hormone (Peram-CAH-I; pQVNFSPNWamide). Of these the Peram-CAH-I was the most frequently bioactive form detected in representatives of four out of the six families studied. The complete AKH preprohormones in the termites studied shared at least an 84% amino acid similarity. In agreement with current phylogenetic scenarios of termites as an internal monophyletic clade nested within cockroaches (Blattaria) in the proximity of the family Blattidae, our phylogenetic analysis of the AKH precursor sequences (in the absence of data for the Cryptocercidae) placed the Blattidae (Periplaneta americana) as a sister group of termites and the AKHs of other cockroach families (Blattellidae and Blaberidae) were more divergent from those of termites. Representatives of the basal termite families Mastotermitidae and Archotermopsidae (but also one rhinotermitid genus Prorhinotermes) occurred separately from the phylogenetically advanced lineage (Rhinotermitidae and Termitidae), and Neotermes (Kalotermitidae) was sister to all other termites included.

Population dynamics of Coccinella septempunctata (Coleoptera: Coccinellidae) in the region of Edremit Gulf in West Anatolia (Mount Ida)Note

Ali ÖZPINAR, Ali Kürşat ŞAHİN, Burak POLAT

Eur. J. Entomol. 115: 418-423, 2018 | DOI: 10.14411/eje.2018.041

This study reports seasonal presence of Coccinella septempunctata L. (Coleoptera: Coccinellidae) in Southeast Turkey, in 2008, 2009 and 2010. Samples were collected from crops in agricultural areas at altitudes of 10 m, 800 m and 1400 m from stands of wild herbaceous plants , and at 1750 m from stone debris fields. First C. septempunctata adults were collected at the beginning of June at Tentcamp (800 m) and Tozlu (1400 m), early in July at Sarikiz (1700 m) when the mean air temperature reached 30°C. Adults became active in spring, after aestivating around Sarikiz and overwintering there under snow. First adults emerged on 2nd April in 2009 around Edremit Gulf when mean air temperature reached 14.8°C. Adult and immature stages of C. septempunctata were recorded attacking aphid populations till the end of June. C. septempunctata was present there for only one period each year during which they completed one generation. Adult individuals of this generation returned to Mount Ida to aestivate. Maximum numbers of adults present on Mount Ida in the first week of August in 2009 and 2010 were recorded. C. septempunctata adults aestivate and overwinter at Sarikiz on Mount Ida after completing their development on aphids in April, May and June around Edremit Gulf.

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