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Results 271 to 300 of 1606:

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.

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.

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.

European database of the life-history, morphological and habitat characteristics of dragonflies (Odonata)Original article

Filip HARABIŠ, Jana HRONKOVÁ

Eur. J. Entomol. 117: 302-308, 2020 | DOI: 10.14411/eje.2020.035

Climate change and an ever-increasing effect of humans on the great majority of freshwater ecosystems have affected not only individual organisms but also the links between them. In order to effectively protect communities or entire freshwater ecosystems, we need to understand how individual organisms react to these changes and the functional interconnections between individual species. This can be achieved by evaluating the functioning of individual species, i.e. their traits. Dragonflies and damselflies are increasingly used as indicators of changes in freshwater ecosystems. Although this taxonomic group is the subject of many ecological studies, there is no comprehensive database of the traits of European species. This is, why we decided to lay the foundations for an European database of dragonfly traits called dragonfly-database.eu, which is mainly based on Web of Science (WOS) publications and several monographs, and currently includes information on 79 European species. The main advantage of our database is that it is open to downloading, uploading, and storing of data. This is extremely important, because a database's applicability increases with the quality of the data it contains. Initially in compiling the database, we encountered several fundamental shortcomings in the knowledge of some often easily measurable traits in, some species. We believe that in combination with new statistical methods dragonfly-database.eu will become a very useful tool for many ecological studies and more effective conservation of threatened species.

Differences in the niches of keratin/chitin feeding moths (Lepidoptera: Tineidae) in bird nests in central JapanOriginal article

Hiroaki SATO, Yoshitsugu NASU, Shiro MURAHAMA, Hiroyuki MATSUMURO, Keisuke UEDA

Eur. J. Entomol. 116: 442-449, 2019 | DOI: 10.14411/eje.2019.045

Some moth larvae feed not on plants but on keratin and/or chitin produced by animals. These substances are polymers and are commonly found in bird nests as feathers and raptor pellets. Many qualitative studies have examined the association of keratin/chitin feeding moths with bird nests. However, few studies have quantified the species composition with respect to type of nest and habitat. Hence, we have studied the degree to which the niches of these moths differ in terms of type of nest and habitat. We set-up open-top nest boxes for the Ural owl Strix uralensis (damp exposed nests from which owl chicks were fledged successfully) and artificial bird nests (mesh bags filled with duck down to imitate dry exposed nests) in a deciduous forest and artificial bird nests in an urban setting in Aichi Prefecture, central Japan, and collected the contents of the nests every two months from June to December 2014. We recorded 592 individuals of five keratin/chitin feeding moth species (Tineidae, Tineinae) from the contents. Using non-metric multidimensional scaling and cluster analysis of the relative abundances of individual species in each type of nest in forest and urban settings, these species were classified into three groups: (1) Monopis longella and M. congestella inhabiting forest, (2) M. flavidorsalis and Niditinea tugurialis mainly in damp exposed nests in forest and (3) N. piercella mainly in dry exposed nests in urban areas. This classification was compared with findings of other studies. As a result, these moths probably have different niches with respect to nest type (damp or dry), keratin/chitin as a source of food (raptor pellets or feathers), and habitat (forest or urban area). Furthermore, we suggest that the evolution of larviparity in M. congestella might be related to its preference for feathers as a source of food for the development of its larvae.

Increased duration of extreme thermal events negatively affects cold acclimation ability in a high-latitude, freshwater ectotherm (Ischnura elegans; Odonata: Coenagrionidae)Original article

Lesley A. SMITH, Lesley T. LANCASTER

Eur. J. Entomol. 117: 93-100, 2020 | DOI: 10.14411/eje.2020.010

Instances of heat waves and cold snaps are becoming more frequent and of increasing duration worldwide. It is well established that short exposure to high or low-temperatures, such as during extreme weather events, often results in adaptive (acclimation/hardening) or maladaptive plastic changes in tolerance of organisms to subsequent thermal stressors. However, little information is available about how the duration of a prior stressful thermal event mediates future organismal thermal responses. Understanding durational effects of thermal conditioning can help predict ectothermic survival in response to novel extreme weather patterns.

Diversity of grasshoppers (Caelifera) recorded on the banks of a Ramsar listed temporary salt lake in AlgeriaOriginal article

Sarah MAHLOUL, Abboud HARRAT, Daniel PETIT

Eur. J. Entomol. 113: 158-172, 2016 | DOI: 10.14411/eje.2016.020

The chotts in Algeria are temporary salt lakes recognized as important wintering sites of water birds but neglected in terms of the diversity of the insects living on their banks. Around a chott in the wetland complex in the high plains near Constantine (eastern Algeria), more than half of the species of plants are annuals that dry out in summer, a situation that prompted us to sample the vegetation in spring over a period of two years. Three zones were identified based on an analysis of the vegetation and measurements of the salt content of the soils. Surveys carried out at monthly intervals over the course of a year revealed temporal and spatial variations in biodiversity and abundance of grasshoppers. The inner zone is colonized by halophilic plants and only one grasshopper species (Dericorys millierei) occurs there throughout the year. Two polyphagous species of Calliptamus, which can feed on halophilic plants migrate from adjacent areas into the inner zone in August to feed on the plants growing there. The other species of grasshoppers remain in outer zones as they are unable to feed on halophilic plants. The greatest abundance of grasshoppers from August to winter was recorded in the inner zone and in spring and early summer in the outer zones. The dependence of D. millierei on bushes of Amaranthaceae and its moderate flight ability, features of the family Dericorytidae, limit this species ability to colonize neighbouring chotts.

Laboratory evaluation of effects of powdered sulphur on the oviposition, fruit detection and behaviour of Drosophila suzukii (Diptera: Drosophilidae) on strawberryOriginal article

Sergio PÉREZ-GUERRERO, José María MOLINA, Cristina MONTIEL, Alberto REDONDO-VILLA, Laura AVIVAR-LOZANO

Eur. J. Entomol. 117: 210-215, 2020 | DOI: 10.14411/eje.2020.022

Drosophila suzukii (Matsumura, 1931) is an invasive pest from South-East Asia that can damage a wide range of soft-skinned fruit crops (especially berries) resulting in serious financial losses. At present, control of D. suzukii is still mainly based on adult-oriented chemical pesticides that is likely to result in resistance and environmental pollution. In this context, alternative methods that are compatible with sustainable management are required. Sulphur and its different formulations are widely used for a long time as a fungicide and insecticide on many crops as it is environmentally-friendly and compatible with organic management. In this study, the effect that powdered sulphur-treated strawberries had on oviposition were evaluated under laboratory conditions in order to confirm the findings of a previous report on blueberries. No-choice and choice experiments were carried out to assess whether powdered sulphur affected the ability of the fly to detect fruit, altered its behaviour or did both. The treatment of strawberries resulted in a reduction of over 79% in the total number of D. suzukii that developed. In the no-choice experiment, there was a reduction of over 70% in the time the flies spent on treated compared to untreated fruit. In the choice experiment, 57% of the females chose untreated and 43% treated strawberries, but this difference was not statistically significant. Furthermore, females took over 75% longer to visit the treated fruit than the control. Sulphur had no noteworthy effect on fly behavior, although oviposition only occurred on untreated fruit indicating that sulphur affects the acceptance and suitability of fruit for females. These results indicate that powdered sulphur could be an appropriate alternative to synthetic-organic insecticides for controlling D. suzukii and is compatible with organic crop management and waste reduction strategies.

Structure of scuttle fly communities (Diptera: Phoridae) in two habitats on a Mediterranean mountainOriginal article

Carlos GARCÍA-ROMERA, José A. BARRIENTOS

Eur. J. Entomol. 114: 203-214, 2017 | DOI: 10.14411/eje.2017.025

Phoridae (scuttle flies) are widely distributed, occur in many types of habitats and are ecologically versatile, which makes them an excellent bioindicator group for evaluating faunal diversity. The structure of scuttle fly communities was compared in two Mediterranean habitats in the Montseny Natural Park (Catalonia, Spain) that differ in vegetation and microclimate: beech forest and highland scrubland. 3684 male individuals belonging to 135 species of scuttle flies were identified. Scuttle flies were more abundant in beech forest than scrubland. Observed and estimated species richness were lower in scrubland than in beech forest, while diversity was similar in both habitats. Community evenness was greater in scrubland than beech forest. Therefore, the percentage of dominant and subdominant species was higher in scrubland than beech forest, while the percentage of rare species was higher in beech forest than scrubland. Scuttle fly species composition was significantly different in the two habitats, but it was similar among plots within the same habitat. Megaselia pectoralis (Wood, 1910) and Megaselia subpleuralis (Wood, 1909) were the dominant species in beech forest, while Megaselia pusilla (Meigen, 1830), Megaselia pumila (Meigen, 1830), Megaselia superciliata (Wood, 1910) and Megaselia diversa (Wood, 1909) were the dominant species in scrubland. Trophic specialization was higher in beech forest than scrubland. Saprophages were the dominant trophic group in beech forest, while fungivores and polyphages were dominant in scrubland. The high biodiversity of scuttle flies recorded in the Montseny Natural Park indicates that there is also a high diversity of other taxa there and that these Mediterranean mountains are of high conservation status.

Density-invariant dispersion indices and fixed precision sequential sampling plans for the peach twig borer Anarsia lineatella (Lepidoptera: Gelechiidae)Original article

Petros DAMOS

Eur. J. Entomol. 115: 642-649, 2018 | DOI: 10.14411/eje.2018.063

Estimating the spatial dispersion of pest arthropods is crucial for the development of reliable sampling programs and one of the main components of integrated pest management. The natural spatial distribution of a population of a species may be random, uniform, or aggregated and can be so classified based on calculation of variance to mean relations and related dispersion indices. In this work some classical density-invariant dispersion indices and related regression models are used for the first time to quantify the spatial dispersion of an important peach pest Anarsia lineatella Zeller (Lepidoptera: Gelechiidae) and construct fixed precision sequential sampling schemes. Taylor's power law, Iwao's patchiness regression and Nachman's model were used to analyse the damage to peaches caused by A. lineatella. All three regression models fit the data well, although the results indicate that Iwao's patchiness model provides a better description of the relationship between variance and mean density. Taylor's b and Iwao's b regression indices were both significantly smaller than 1, indicating that the distribution of individuals was uniform rather than random or aggregated. According to Green's and Kuno's models, the minimum sample size at the precision level of 0.2 varies from 3 samples, when total population density is more than 3 larvae/sample, to 10 samples, when population density is between 1 and 2 larvae/sample. Kuno's fixed sampling plan indicates that a small number of samples (i.e., 3-10 branches with fruit) is sufficient to estimate the mean population density of A. lineatella larvae with a precision of 0.2. The Resampling for validation of sampling plans (RVSP) method confirmed that the average level of precision of the fixed sequential plans matched the desired precision in most cases. The sampling plan presented here provides a level understanding of A. lineatella spatial ecology suitable for pest management decisions.

Pupal traits and adult emergence in the pine processionary moth Thaumetopoea pityocampa (Lepidoptera: Notodontidae) are affected by pupal densityOriginal article

Carmelo P. BONSIGNORE, Francesco MANTI, Elvira CASTIGLIONE, Andrea BATTISTI

Eur. J. Entomol. 116: 320-329, 2019 | DOI: 10.14411/eje.2019.035

The expectation is that the phenology of an herbivore is influenced by abiotic factors and its own population density during development. In this study, we investigated how the pupal density affected the pupal traits and emergence of Thaumetopoea pityocampa moths over a period of 3 years in two clearings in a pine forest. The pupae were larger in years when the pupal density was high and in the clearing exposed to less solar radiation. There was no relationship between the time of pupation and pupal size. Large pupae were positively correlated with an early emergence of adult moths and a longer period of adult emergence. Up to 13.9% of the pupae developed without cocoons, especially in years when they were abundant, but this did not affect the emergence of the moths. Incidence of pupal diapause was density-dependent and only occurred at a low level in dense populations. Overall, our results indicate that gregariousness confers important fitness-related advantages in this species.

Stones on the ground in olive groves promote the presence of spiders (Araneae)Original article

Jacinto BENHADI-MARÍN, José A. PEREIRA, José A. BARRIENTOS, José P. SOUSA, Sónia A.P. SANTOS

Eur. J. Entomol. 115: 372-379, 2018 | DOI: 10.14411/eje.2018.037

Spiders are generalist predators that contribute to the control of pests in agroecosystems. Land use management determines habitats including refuges for hibernation and aestivation. The availability of shelters on the ground can be crucial for maintaining populations of spider within crops. We studied the effect of the number of stones on the surface of the soil on the spider community in selected olive groves in Trás-os-Montes (northeastern Portugal). The number of stones significantly influenced the overall diversity of spiders, abundance of immature individuals and abundance of ground hunters. Agricultural management practices aimed at the conservation of soil microhabitats such as hedgerows, stonewalls and stones on the ground should be promoted in order to maintain or increase the number of shelters for potential natural enemies of pests.

The entomofauna on Eucalyptus in Israel: A reviewReview

Zvi MENDEL, Alex PROTASOV

Eur. J. Entomol. 116: 450-460, 2019 | DOI: 10.14411/eje.2019.046

The first successful Eucalyptus stands were planted in Israel in 1884. This tree genus, particularly E. camaldulensis, now covers approximately 11,000 ha and constitutes nearly 4% of all planted ornamental trees. Here we review and discuss the information available about indigenous and invasive species of insects that develop on Eucalyptus trees in Israel and the natural enemies of specific exotic insects of this tree. Sixty-two phytophagous species are recorded on this tree of which approximately 60% are indigenous. The largest group are the sap feeders, including both indigenous and invasive species, which are mostly found on irrigated trees, or in wetlands. The second largest group are wood feeders, polyphagous Coleoptera that form the dominant native group, developing in dying or dead wood. Most of the seventeen parasitoids associated with the ten invasive Eucalyptus-specific species were introduced as biocontrol agents in classical biological control projects. None of the polyphagous species recorded on Eucalyptus pose any threat to this tree. The most noxious invasive specific pests, the gall wasps (Eulophidae) and bronze bug (Thaumastocoris peregrinus), are well controlled by introduced parasitoids. Potential entomological hazards of Eucalyptus in Israel are most likely to originate from the Australian insect fauna.

Host-based genetic divergence in populations of an exotic spiralling whitefly, Aleurodicus dispersus (Hemiptera: Aleyrodidae)Original article

Thangavel BOOPATHI, Subbarayalu MOHANKUMAR, GAYACHARAN, Manickavasagam Pillai KALYANASUNDARAM, Soibam Basanta SINGH, Ramaraju ARAVINDRAJ, Bangaru PREETHA, Kandasamy SANKARI MEENA, Kothandaraman CHANDRASEKAR

Eur. J. Entomol. 116: 221-228, 2019 | DOI: 10.14411/eje.2019.024

The morphology, physiology, behaviour and ecology of spiralling whitefly, Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae) on different host plants differ greatly. The genetic differences between the A. dispersus populations on 17 host plants were evaluated in the current study. Microsatellite markers were used to identify the presence of host-related genetic variation among A. dispersus populations. Our research clearly shows that there is a significant amount of genetic divergence among the A. dispersus populations on 17 host plants in India. The spiralling whitefly on acalypha and calotropis were genetically more distinct than whiteflies on other host plants. Various population genetic parameters, like heterozygosity, Nei's genetic distance, fixation indices (FST), source of genetic variation in AMOVA, etc. indicate that populations of spiralling whiteflies differ greatly genetically, probably because the spiralling whitefly populations on the Indian sub-continent came from multiple sources. The results of this study have implications for the quarantine protection strategy against this invasive pest.

Cascading ecological effects caused by the establishment of the emerald ash borer Agrilus planipennis (Coleoptera: Buprestidae) in European Russia

Marina J. ORLOVA-BIENKOWSKAJA

Eur. J. Entomol. 112 (4): 778-789, 2015 | DOI: 10.14411/eje.2015.102

Emerald ash borer, Agrilus planipennis, is a destructive invasive forest pest in North America and European Russia. This pest species is rapidly spreading in European Russia and is likely to arrive in other countries soon. The aim is to analyze the ecological consequences of the establishment of this pest in European Russia and investigate (1) what other xylophagous beetles develop on trees affected by A. planipennis, (2) how common is the parasitoid of the emerald ash borer Spathius polonicus (Hymenoptera: Braconidae: Doryctinae) and what is the level of parasitism by this species, and (3) how susceptible is the native European ash species Fraxinus excelsior to A. planipennis. A survey of approximately 1000 Fraxinus pennsylvanica trees damaged by A. planipennis in 13 localities has shown that Hylesinus varius (Coleoptera: Curculionidae: Scolytinae), Tetrops starkii (Coleoptera: Cerambycidae) and Agrilus convexicollis (Coleoptera: Buprestidae) were common on these trees. Spathius polonicus is frequently recorded. About 50 percent of late instar larvae of A. planipennis sampled were parasitized by S. polonicus. Maps of the distributions of T. starkii, A. convexicollis and S. polonicus before and after the establishment of A. planipennis in European Russia were compiled. It is hypothesized that these species, which are native to the West Palaearctic, spread into central European Russia after A. planipennis became established there. Current observations confirm those of previous authors that native European ash Fraxinus excelsior is susceptible to A. planipennis, increasing the threat posed by this pest. The establishment of A. planipennis has resulted in a cascade of ecological effects, such as outbreaks of other xylophagous beetles in A. planipennis-infested trees. It is likely that the propagation of S. polonicus will reduce the incidence of outbreaks of A. planipennis.

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.

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.

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.

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