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Results 121 to 150 of 1442:

Ecological and molecular diversity of Eulachnini aphids (Hemiptera: Aphididae: Lachninae) on coniferous plants in LithuaniaOriginal article

Jekaterina HAVELKA, Jurij DANILOV, Rimantas RAKAUSKAS

Eur. J. Entomol. 117: 199-209, 2020 | DOI: 10.14411/eje.2020.021

Based on research carried out from 2016 to 2018 there are twenty-six species of aphids of the tribe Eulachnini in Lithuania. Seventeen are members of the subgenus Cinara of the genus Cinara, three of the subgenus Cupressobium and two of the subgenus Schizolachnus. In addition, there are four species of the genus Eulachnus. Summarized information on the distribution and host specificity of Eulachnini in Lithuania is presented. Nine species were in all climatic regions of Lithuania: C. (Cinara) brauni, C. (Cinara) hyperophila, C. (Cinara) neubergi, C. (Cinara) piceicola, C. (Cinara) pinea, C. (Cinara) pini, C. (Cinara) pruinosa, C. (Cupressobium) cupressi and C. (Cupressobium) juniperi. Five species of Lithuanian Eulachnini inhabit host plants of the genus Picea, three live on Larix, thirteen on Pinus, one on Abies, one on Thuja and three on Juniperus. Cinara (Cinara) piniphila was recorded on Pinus mugo and C. (Cinara) nuda on Pinus heldreichii for the first time. Partial COI and EF-1α sequences of C. (Cinara) hyperophila, C. (Cinara) pilosa and C. (Cinara) piceicola were obtained for the first time. Partial sequences of mitochondrial (COI) and nuclear (EF-1α) DNA of Lithuanian samples were used to explore molecular diversity using NJ trees, Automatic Barcode Gap Discovery (ABGD), General Mixed Yule Coalescent (GMYC) and Poisson Tree Processes (PTP). Species delimitation using GMYC (both on COI and EF-1α sequences), PTP (BI on COI) and ABGD (EF-1α) were the most consistent with traditional classifications. Pairwise between-species sample divergences (COI and EF-1α fragments) of the samples of the species complex C. (Cinara) pinea - C. (Cinara) piniphila indicate it is composed of a single species. Of the species of aphids that live on conifers, there are seven species of the tribe Eulachnini that are likely to shortly colonize Lithuania.

Inoculation of cucumber plants with Beauveria bassiana enhances resistance to Aphis gossypii (Hemiptera: Aphididae) and increases aphid susceptibility to pirimicarbOriginal article

Mohammad HOMAYOONZADEH, Mojtaba ESMAEILY, Khalil TALEBI, Hossein ALLAHYARI, Stuart REITZ, J.P. MICHAUD

Eur. J. Entomol. 119: 1-11, 2022 | DOI: 10.14411/eje.2022.001

The entomopathogen Beauveria bassiana (Bals.) Vuill. (Ascomycota: Hypocreales) can colonize plants endophytically and stimulate the production of secondary plant metabolites with anti-herbivore activities. We assayed the topical virulence of B. bassiana to Aphis gossypii Glover (Hemiptera: Aphididae), the effects of cucumber inoculation with this fungus on plant metabolites, and the physiological consequences for aphids that fed on these plants. Assays were conducted with both the commercial formulation of B. bassiana, 'Naturalis®-L', at the recommended concentration of 1.5 ml / L (yielding a spore concentration of 2.3 × 107 CFU per ml), and with a similar concentration of the isolated fungal strain. Topical application of 0.03 ml of solution per cm2, or 1 × 103 CFU, caused 100% mortality to A. gossypii adults after seven days, whether Naturalis®-L or the isolate alone was used. The fungus grew endophytically into foliage when sprayed on cucumbers at the 2-leaf stage and concentrations of alkaloids, flavonoids, phenols, hydrogen peroxide, and total chlorophyll were higher than in control plants 28 days after inoculation. Malondialdehyde content, plant growth, and total yield were unaffected by B. bassiana inoculation. Aphids fed on B. bassiana-inoculated plants for 24 h had reduced activities of detoxifying enzymes (glutathione-S-transferase, carboxylesterase, and acetylcholinesterase) compared to controls. Activities of digestive enzymes, (lipase, α-amylase, α-glucosidase, and aminopeptidase) were reduced in aphids from inoculated plants, which exhibited higher activities of superoxide dismutase, ascorbate peroxidase, and phenoloxidase, but lower catalase activity. Energy reserves (lipids, protein, and glycogen) were lower in aphids from inoculated plants, and they exhibited reduced fecundity, longevity, and reproductive periods, and a 50% reduction in the LC50 of pirimicarb. Thus, in addition to causing direct pathogenicity, inoculation of plants with B. bassiana negatively impacted A. gossypii physiology and reproductive performance and could usefully complement other strategies for managing cotton aphids on greenhouse cucumber.

The effect of conductor wires of different metals on the amount of honey bee (Apis mellifera; Hymenoptera: Apidae) venom collected and its chemical contentOriginal article

Nazim TURAN, Cengiz ERKAN

Eur. J. Entomol. 120: 366-371, 2023 | DOI: 10.14411/eje.2023.040

Researchers have been interested in honey bee, Apis mellifera L., venom for many years, but the previous studies focused mainly on its pharmacological properties and the factors affecting its production and chemical content were less well evaluated. This research aims to investigate the potential effect of the method of collecting bee venom on its chemical content. To achieve this, brass, steel, aluminium and copper wire conductors were used. This research was carried out at Van YYU Beekeeping Application and Research Centre, where the venom was collected dry on glass plates from 16 Caucasian F1 honey bee colonies. The quantity produced and its composition in terms of melittin, apamin and phospholipase A2 were determined after storage. Duncan and LSD Multiple Comparison tests on the amounts of venom collected using aluminium, copper, steel and brass wires for conducting electricity, revealed it was 21.03 ± 3.50, 15.08 ± 0.32, 22.38 ± 6.35 and 30.35 ± 3.66 mg, respectively. Although these values differed significantly (p < 0.05), the chemical content of the bee venom was the same. The colour of the venom was associated with the material of the electrical conductor used. It was concluded that it would be beneficial to carry out further studies using more colonies along with using residue analysis.

Measuring saproxylic beetle diversity in small and medium diameter dead wood: The "grab-and-go" method

Anna L.M. MACAGNO, Sönke HARDERSEN, Gianluca NARDI, Giuseppe LO GIUDICE, Franco MASON

Eur. J. Entomol. 112 (3): 510-519, 2015 | DOI: 10.14411/eje.2015.049

Saproxylic organisms play a key role in a variety of forest ecosystem functions, which result in an increase in overall forest productivity and biodiversity. At present, dead wood is frequently removed from exploited forests. Estimating the effect of current forest management on biodiversity, and what gain in biodiversity would result from implementing restoration programs, requires the use of standardized sampling protocols. These protocols need to be suitable for use in different sampling areas and cost effective. In this paper, we developed, tested, and optimized a method for sampling saproxylic insects during a single visit to a sample site (i.e., the "grab-and-go" method). In the spring of 2011, we collected samples of downed decaying small and medium diameter wood debris in two Italian beech forests: Sega di Ala (Alps) and Vallombrosa (Apennines). We used ex situ emergence traps in the laboratory to collect the beetles emerging from the wood sampled. At both sites, the minimum number of wood samples that resulted in a satisfactory description of the saproxylic beetle assemblage was 20. Wood moisture, mean diameter, and geographical location were significantly associated with the beetle assemblages. We discuss the implications of using the "grab-and-go" method in large-scale forest monitoring programs. In this context, we recommend collecting at each site twenty 50 cm-long samples of wood lying on top of the litter, with a diameter of 12 ± 2 cm, cortex cover < 50%, and at Hunter's stage of decay class 2.

Taxonomic and functional differentiation of spiders in habitats in a traditional olive producing landscape in ItalyOriginal article

Malayka S. PICCHI, Gionata BOCCI, Ruggero PETACCHI, Martin H. ENTLING

Eur. J. Entomol. 117: 18-26, 2020 | DOI: 10.14411/eje.2020.002

Annual crops are generally assumed to host simplified arthropod communities that depend on immigration from the surrounding landscape. Perennial, low-input crops such as olive groves are likely to depend less on immigration from other habitats, however, studies on the landscape ecology of perennial crops are scarce. This paper studies the assemblages of arboreal spiders in three types of habitats adjoining olive groves: woods, garigue and other cultivated olive groves in a traditional olive producing landscape. Spiders were sampled during summer and the three types of habitats were compared in terms of species, families and functional groups in order to determine differences in diversity and the potential for spider spillover. As is often reported for annual crops, olive groves had a lower alpha and beta diversity than more natural habitats in terms of species, with a strong dominance of a single species, Frontinellina frutetorum (C.L. Koch, 1834). Differences in diversity between olive groves and natural habitats were not significant at family or functional group levels. With the possible exception of orb weavers, this study indicates that the spiders that were common in olive groves did not occur at higher densities in habitats that were more natural. This indicates there is limited spillover between perennial crops and other late-successional habitats. The enhancement of spiders in olive orchards for pest control may thus depend more on local management than on the presence of semi-natural habitats as a source of immigration.

Movement, demography and behaviour of a highly mobile species: A case study of the black-veined white, Aporia crataegi (Lepidoptera: Pieridae)Original article

Jure JUGOVIC, Mitja ČRNE, Martina LU®NIK

Eur. J. Entomol. 114: 113-122, 2017 | DOI: 10.14411/eje.2017.016

We studied the demography, movement, behaviour and choice of nectar plants by adults of Aporia crataegi. This study was done in a dense network of different types of habitats (total size of study area 16.26 ha) from open landscape to shrubland, the latter being a result of abandonment of traditional agricultural practices such as extensive mowing and grazing. Total population size was estimated to be approximately 1700 and 2700 for females and males, respectively. Median and maximum distances moved by males were 134 and 3493 m, and by females 138 and 3165 m, respectively. The average lifespan was ca. 7.1 and 7.5 days, with maximum recorded lifespans of 21 and 17 days for males and females, respectively. The greater capture probability recorded for males indicates their high activity, as they spend most of their time in flight patrolling and searching for mates. A parabolic recruitment curve and protandry were also recorded. Both sexes are highly mobile. The spatial distribution of both sexes was roughly similar. The adult behaviour differed in different habitats, with more time spent feeding and resting when nectar plants were plentiful and more time spent flying when they were rare. Although adults utilized nine nectar sources, only two were recorded in over 80% of all the feeding occasions. In order to re-establish open grassland with some shrubland, traditional and mosaic management of the landscape should be revived at least to some extent.

Sexual dimorphism and phylogenetic position of Chilodendron (Coleoptera: Curculionidae: Scolytinae) - a long isolated lineage endemic to MadagascarOriginal article

Bjarte H. JORDAL

Eur. J. Entomol. 119: 152-158, 2022 | DOI: 10.14411/eje.2022.017

Chilodendron Schedl, 1953 is resurrected as a valid genus based on Chilodendron planicolle Schedl, 1953. This is the only representative of the tribe Hylesinini Erichson, 1836 found on Madagascar and a molecular phylogenetic analysis of several genes supports a position separate from Hylesinopsis Eggers, 1920 and other putatively close relatives. It is likely that Chilodendron is the oldest living lineage of bark beetles on Madagascar and possibly originated in the late Cretaceous not long after the separation of Madagascar from the Indian subcontinent.

The role of 10-hydroxy-Δ2-decenoic acid in the formation of fibrils of the major royal jelly protein 1/apisimin/24-methylenecholesterol complex isolated from honey bee (Apis mellifera) royal jellyOriginal article

Anja BUTTSTEDT

Eur. J. Entomol. 119: 448-453, 2022 | DOI: 10.14411/eje.2022.047

Queen larvae of the honey bee (Apis mellifera) are fed with royal jelly, a glandular secretion produced by the hypopharyngeal and mandibular glands of worker honey bees. The necessary consistency of royal jelly is dependent on a protein-sterol complex (MRJP14/apisimin4/24MC8). At low pH, this complex forms fibrillar structures, which increase the viscosity of royal jelly. While the proteins in this complex are produced in the hypopharyngeal gland, the low pH is achieved by the secretion of the mandibular gland, which contains fatty acids. It is shown for the first time that fibril formation of MRJP14/apisimin4/24MC8 is not only induced by low pH via a buffer system, but also by the addition of the major fatty acid 10-hydroxy-Δ2-decenoic acid (10-HDA) of the mandibular gland secretion. This result further substantiates that fibril formation of the MRJP14/apisimin4/24MC8 complex only occurs after mixing the hypopharyngeal and mandibular gland secretions.

Biometric differences between several populations of Cordulegaster boltonii (Odonata: Cordulegastridae) in Ibero-Maghrebian areaNote

Patricia CASANUEVA, Tomás SANTAMARÍA, María Á. HERNÁNDEZ, Luis F. SÁNCHEZ-SASTRE, Amilcar TEIXEIRA, Nard BENNAS, Mohamed EL HAISSOUFI, Manuel FERRERAS-ROMERO, Francisco CAMPOS

Eur. J. Entomol. 117: 260-264, 2020 | DOI: 10.14411/eje.2020.028

Biometric data of the exuviae of female larvae of the dragonfly Cordulegaster boltonii collected in Portugal, Spain and Morocco were analysed to determine whether the size of three exuvial structures measured differed depending on the geographic localities of the populations. Based on the results recorded for the 16 populations studied, head width was negatively correlated with latitude and the greatest length of the gonapophysis was recorded for the Iberian populations at the centre of this peninsula. Multivariate cluster analysis revealed a clear separation of the Moroccan population. A second cluster separated the southernmost population (Sierra Nevada) from the remaining Iberian populations. Four population groups were distinguished: those located in watercourses in the north and central area of the Iberian Peninsula, those in Iberian watercourses in the East and Middle South, the Sierra Nevada and North Morocco. Some of these results coincide with the results of genetic studies of other authors.

Presence after three decades of red wood ants (Formica rufa group; Hymenoptera: Formicidae) in forests in an agricultural landscapeOriginal article

Harry J.M. VAN BUGGENUM

Eur. J. Entomol. 119: 85-91, 2022 | DOI: 10.14411/eje.2022.009

Conducting a repeat study of the presence of mound-building red wood ants (Formica rufa group) after a period of 30 years has rarely been done in Europe. From 1990 to 2020 such a study was done in an intensively used agricultural landscape with fragments of forest in the South-Eastern part of The Netherlands. In 1990, 280 nest mounds of three species of red wood ants and a hybrid were found in the forests and along forest edges. The highest occupancy was in forests of > 25 ha. The connectivity between the forest fragments mainly determined their presence. In 2020, only 160 nest mounds were found. The development of the colonies differed for Formica polyctena Förster, 1850 (slight decrease), F. rufa Linnaeus, 1761 (substantial increase) and F. pratensis Retzius, 1783 (strong decrease). The differences between the species in this highly fragmented landscape may be due to differences in their colonization strategies of either nest splitting or producing swarms of young queens. Furthermore, the analyses show that the type of environment (in a forest or along a forest edge) determines the probability of extinction or settlement. There is a need to undertake management measures to prevent the extinction of species of red wood ants in the area studied. These measures include creating small clearings in dense forests, reducing shading due to overgrowing shrubs or herbaceous plants, and creating buffer zones around intensively manured fields. More long-term monitoring is needed in Europe to compare the circumstances in different regions, detect trends and evaluate the effects of protection measures.

Seasonal and geographical adaptations in the parthenogenetic stick insect, Ramulus mikado (Phasmatodea: Phasmatidae)Ivo Hodek special issueOriginal article

Keiji NAKAMURA, Yuuki FUKUSHIMA

Eur. J. Entomol. 119: 354-361, 2022 | DOI: 10.14411/eje.2022.036

Seasonal and geographical adaptations in terms of obligatory embryonic diapause in the parthenogenetic stick insect, Ramulus mikado, were studied. First and second instar nymphs were collected at locations at three latitudes in Japan and reared in the laboratory under a photoperiod of 16L : 8D or 12L : 12D at 25°C. Their eggs were kept at 30°C for 30 or 60 days after oviposition, but no eggs hatched. Hatching was observed more than 100 days after transfer from 30°C to 15°C. The long period between transfer and hatching indicate that eggs in an early embryonic stage of development enter diapause at high-temperatures. The time from oviposition to hatching of eggs laid by adults that originated from the three locations kept under constant conditions between 15 and 25°C were compared. In all these experiments, eggs laid by individuals originating from high latitudes took longer to hatch. The eggs of those originating from Okayama and Ehime did not hatch at 25°C. However, more than 80% of the eggs of those that originated from the northernmost population hatched. Hatching before winter was observed when the eggs of those that originated from the northern population were placed outdoors in Okayama, even when the maternal insects were reared under long-day conditions in the laboratory. These findings indicate that univoltine R. mikado enters diapause twice during embryonic development, which enables it survive adverse conditions in summer and winter, respectively. Furthermore, diapause intensity was lowest in insects that originated from the lowest latitude.

The circadian clock gene (Clock) regulates photoperiodic time measurement and its downstream process determining maternal induction of embryonic diapause in a cricketIvo Hodek special issueOriginal article

Shin G. GOTO, Masatoshi NAGATA

Eur. J. Entomol. 119: 12-22, 2022 | DOI: 10.14411/eje.2022.002

In response to short days in autumn, most temperate multivoltine insects enter diapause, a state in which development or reproduction is suppressed or arrested, which serves to coordinate their development and physiology (or that of offspring) with annual changes in the environment (i.e. photoperiodism). This response is mediated by a measurement of time based on photoperiod (photoperiodic time measurement), which is thought to be regulated by a circadian clock. However, some studies also demonstrate the involvement of the circadian clock in an output process that generates phenotypes associated with diapause. To gain further insight into this, we silenced the Clock (Clk) gene, the main regulator of the circadian clock, in the band-legged ground cricket Dianemobius nigrofasciatus (Orthoptera: Trigonidiidae). Silencing the Clk gene using RNA interference (Clk RNAi) in female crickets resulted in abnormal circadian rhythms under constant darkness and light-dark conditions, thereby indicating the central role of this gene in the circadian clock mechanism. Clk RNAi females exhibited long-day oviposition behaviour, even when reared under short-day conditions, thereby indicating the involvement of Clk in photoperiodic time measurement. In addition, Clk RNAi females immediately laid non-diapause-type eggs, which was not recorded in control females under either short-day or long-day conditions and cannot be explained in terms of dysfunction of photoperiodic time measurement. Accordingly, we speculate that Clk could also be involved in a downstream process that results in the laying of diapause-type eggs.

Habitat of Carabus zawadzkii (Coleoptera: Carabidae) in the Eastern CarpathiansOriginal article

Peter GAJDO©, Stanislav DAVID, Oto MAJZLAN, Tomáą JÁSZAY, Ján ČERNECKÝ

Eur. J. Entomol. 119: 285-299, 2022 | DOI: 10.14411/eje.2022.030

This paper provides an analysis of the rare and important Natura 2000 species Carabus zawadzkii in terms of its ecological niche, conservation status and relationship with other Carabus species in carabid assemblages. Published sources are inconsistent in defining the habitats in which this species occurs. Therefore, a large part of this paper is dedicated to identifying the relationship of Carabus zawadzkii with particular non-forest habitats based on field research conducted in 2011-2013. The results revealed an unexpected affinity of this species for non-forest habitats in addition to the know relationship with forest habitats. Further analysis, using additional field data collected over the period 2013-2021, also focused on the assessment of the current conservation status of this rare species. Overall, the population of this species seems stable; however, to improve its conservation status it requires particular management measures. Important conservation measures include periodic extensive mowing of mountain hay meadows. This species' seasonal dynamics provides important information for nature conservationists. It is important to carry out research on this species in May, when it is most active. Presented results provide the most comprehensive overview of the ecological preferences and occurrence of this important and very rare Carpathian species.

Ecological niche modelling of species of the rose gall wasp Diplolepis (Hymenoptera: Cynipidae) on the Iberian PeninsulaOriginal article

Sara SARDÓN-GUTIÉRREZ, Diego GIL-TAPETADO, José F. GÓMEZ, José L. NIEVES-ALDREY

Eur. J. Entomol. 118: 31-45, 2021 | DOI: 10.14411/eje.2021.004

Diplolepis (Hymenoptera: Cynipidae) are gall wasps that induce conspicuous galls on Rosa spp. (Rosaceae). These species are distributed globally and in Europe some are especially common and are founder organisms of biological communities composed of different insects. However, the ecological niches of these species have not been studied in detail. We modelled the potential distributions of these species using the locations of the galls of the four most abundant species of Diplolepis on the Iberian Peninsula (Diplolepis mayri, Diplolepis rosae, Diplolepis eglanteriae and Diplolepis nervosa, the galls of latter two are indistinguishable) using four different algorithms and identified the resulting consensus for the species. We compared the potential distributions of these species, considering their spatial complementarity and the distributions of their host plants. We found that D. mayri and D. eglanteriae/nervosa have complementary distributions on the Iberian Peninsula. The former species is found in the Mediterranean region, while D. eglanteriae and D. nervosa are distributed mainly in the Eurosiberian region. Diplolepis rosae has the widest distribution on the Iberian Peninsula. Our models constitute the first effort to identify suitable areas for species of Diplolepis species on the Iberian Peninsula and could be useful for understanding the evolutionary ecology of these species throughout their distribution in the western Palearctic.

Distribution of butterflies (Lepidoptera) in a successional mosaic of Mediterranean mountain habitatsOriginal article

Jesús SÁNCHEZ-DÁVILA, José A. MOLINA, Francisco J. CABRERO-SAÑUDO

Eur. J. Entomol. 119: 159-169, 2022 | DOI: 10.14411/eje.2022.018

The distribution of butterflies was analysed in a mosaic of different types of habitats in a typical Ibero-Supramediterranean plant landscape. This mosaic landscape is composed of oak forests (Quercus pyrenaica) and their corresponding shrub and grassland successional communities. The observed patterns were based on butterfly-flower interactions in two consecutive years (2017-2018) recorded in different habitats. The results of the nestedness analysis indicated that the same butterfly community exploits all of the successional plant-communities, but some differences due to the availability of flowers. The foraging for nectar sources was mostly restricted to a few flowering plants: Rubus ulmifolius, Carduus carpetanus, Thymus pulegioides and Dianthus deltoides. Some butterflies changed their flower-visiting patterns over the two years studied. The distribution of butterflies was strongly linked to the distribution of their preferred nectar sources and changes in the use of these sources modified habitat use. The area of Rubus shrubland is a small but highly used habitat in this area, given the presence of Rubus ulmifolius, a plant species with high coverage and abundance of nectar, makes this area much better for foraging than other habitats. The Cytisus and Rubus shrublands were used more than grassland, indicating that seral habitats can be more valuable than traditional open grassland and forest habitats for butterflies.

Revision, phylogeny and phylogeography of the cicada genus Auritibicen (Hemiptera: Cicadidae), with descriptions of ten new speciesOriginal article

Xu WANG, Masami HAYASHI, Cong WEI

Eur. J. Entomol. 115: 53-103, 2018 | DOI: 10.14411/eje.2018.007

We review the cicada genus Auritibicen Lee, 2015 based on the description of ten new species: A. aethus sp. n., A. daoxianensis sp. n., A. pallidus sp. n., A. rotundus sp. n., A. curvatus sp. n., A. purus sp. n., A. parvus sp. n., A. gracilis sp. n., A. septatus sp. n. and A. lijiangensis sp. n. Auritibicen shikokuanus (Kato, 1959) is confirmed to be a synonym of Auritibicen kyushyuensis (Kato, 1926). Diagnoses and descriptions, along with illustrations of the structure of male genitalia, are provided for all Auritibicen species. The systematics of Auritibicen is elucidated using both morphological and molecular characterization. Thirty-five morphological characters of the 24 species of Auritibicen and one outgroup taxon, Chremistica ochracea (Walker, 1850), were scored. Morphological phylogenetic analyses reveal the relationships among related species of Auritibicen, which are supported by a number of morphological characters. The mitochondrial gene fragments of Cytochrome Oxidase I (COI) of 11 species of Auritibicen and two outgroup Lyristes species were analyzed and yielded identical robust phylogenetic trees. The phylogram based on a Bayesian analysis of both morphological and molecular data is similar to the ML/BI topologies based only on the molecular data. The molecular phylogenetic analysis indicates that species of Auritibicen are structured phylogeographically, with related species clustered into three lineages. The divergence time estimated based on molecular data indicates that the divergence of Auritibicen from Lyristes occurred during the Miocene, and the most recent common ancestor (tMRCA) of Auritibicen evolved during the Pliocene. However, the time when the main divergence events of species of Auritibicen occurred was the Pleistocene. From the combination of the phylogeny and updated geographical distributions, we infer that the center of distribution of Auritibicen could be Southwest China (e.g., Sichuan and Yunnan Provinces), from where species of this genus spreaded northeastwards to Shaanxi, Hubei and other provinces along the Qinling and Daba Mountains, then further northeastwards to Hebei Province in China and also to Far East Russia, the Korean Penisula, and Japan.

The life cycles of Boyeria irene and Onychogomphus uncatus (Odonata: Aeshnidae, Gomphidae) in western Spain: A biometric studyOriginal article

Tatiana VELASCO-VILLANUEVA, Francisco CAMPOS, Ulf NORLING, Manuel FERRERAS-ROMERO

Eur. J. Entomol. 115: 684-696, 2018 | DOI: 10.14411/eje.2018.067

Co-occurrence of species with similar trophic requirements, such as odonates, seems to depend both on them occupying different microhabitats and differing in their life-cycles. The life cycles of the dragonflies Boyeria irene and Onychogomphus uncatus were studied in two consecutive years, mainly by systematic sampling of larvae in seven permanent head courses that constitute the upper basin of the River Águeda, western Spain, in the central part of the ranges of these two species. The size ranges of the last five larval stadia of both species were established based on biometric data. The eggs of the egg-overwintering aeshnid hatched in late spring and early summer and for the gomphid hatching peaked in middle-late summer. Both species showed mixed voltinism with "cohort splitting". B. irene had a dominant three-year development (partivoltinism), with some developing in two years (semivoltinism). O. uncatus requires four, sometimes three years to complete development (all partivoltine). B. irene larvae spent the winter before emergence in the last three, maybe four stadia, as a "summer species". O. uncatus mainly behaved as a "spring species", most larvae spending the last winter in the final larval stadium.

Gastrophysa viridula (Coleoptera: Chrysomelidae) in the Czech Republic: Decline in a once abundant invasive oligophagous consumer of RumexOriginal article

Zdenka MARTINKOVA, Alois HONEK, Pavel SASKA

Eur. J. Entomol. 118: 250-254, 2021 | DOI: 10.14411/eje.2021.026

While the progress of the spread of invasive species of insects in new geographical areas are usually intensively monitored, the decline of these species often escape attention and is poorly documented. In this study, we record the decline in abundance of Gastrophysa viridula (DeGeer), an invasive oligophagous consumer of dock (Rumex spp.). This species originally inhabited Alpine regions. In the late 1800s, G. viridula was recorded in montane areas in the Czech Republic and then throughout this country. Gastrophysa viridula was very abundant in 1995-1999, when we found it in all of the 177 stands of R. obtusifolius inspected in western Czech Republic. In a repeated study of its occurrence in the same area from 2019-2020, this species was present in < 30% of 434 of the stands inspected and was only abundant (≥ 55% of plants in the stand infested by G. viridula) in < 4% of these stands. Thus the local occurrence and abundance of G. viridula had decreased significantly. Of the possible reasons for this decline the most probable are the effect of climate warming on host plant seasonality, changes in agricultural use of grasslands and fragmentation of large stands of dock.

Biogeography and habitat preferences of red wood ants of the Formica rufa group (Hymenoptera: Formicidae) in Finland, based on citizen science dataOriginal article

Jouni SORVARI

Eur. J. Entomol. 119: 92-98, 2022 | DOI: 10.14411/eje.2022.010

Red wood ants (RWA) of the Formica rufa group are ecosystem engineers and important species in boreal and temperate forests. However, the permanent and temporal loss of forest habitats is a serious threat to their existence and is likely to increase with climate change. Due to the current threat of losing species, quick actions are needed. Reported here is the biogeography, relative abundance and habitat preferences of five species of RWA in Finland based on citizen science data. Species that occur in the lowlands of the Alps also occur throughout the southern parts of Finland. Only two of the five species, F. aquilonia Yarrow, 1955 and F. lugubris Zetterstedt, 1838, were common throughout the country, including northern Lapland. As their name suggests, RWAs occur mostly in forests and forest edges, but they also sometimes inhabit open or semi-open yards, mires and meadows. The most forest-specialist species is F. aquilonia and the least F. rufa Linnaeus, 1761. Surprisingly, the meadow wood ant F. pratensis Retzius, 1783 is the second most forest dwelling species, however, its preference for forest edges is clearly higher than for forest interiors. Based on current data, F. rufa may be the most tolerant of living close to buildings as its relative abundance in yards was much higher than that of the other species. The data obtained on distributions and relative abundances could be compared in the future with the results of similar surveys to detect changes in species distributions, relative abundances and habitat preferences.

Screening of immune-related genes against bacterial infection in Ostrinia furnacalis (Lepidoptera: Crambidae)Original article

Wan ZHOU, Zengxia WANG, Baohong HUANG

Eur. J. Entomol. 119: 388-397, 2022 | DOI: 10.14411/eje.2022.040

Ostrinia furnacalis Guenée is an important pest of maize. The current use of microbial agents to control O. furnacalis have been relatively successful. However, upon infestation with microorganisms, O. furnacalis initiates an innate immune response to defend itself against foreign invaders. Therefore, understanding the immune mechanisms in O. furnacalis is important to ensure a more efficient use of microbial agents for the control of this pest. In the present study, a gram-positive bacterium, Staphylococcus aureus, and a gram-negative bacterium, Escherichia coli, were used to induce an immune response in O. furnacalis. Transcriptomic sequencing was then used to screen for genes that were significantly differentially expressed after microbial induction and sequence comparison and phylogenetic analysis to identify immune-related genes the expression of which was significantly induced. The results show a large number of genes were differentially expressed in O. furnacalis after microbial induction, the majority of which were immune-related genes. The expression of some immune-related genes such as those encoding antimicrobial peptides, peptidoglycan recognition proteins and serine protease inhibitors were strongly induced. Overall, our study increases the understanding of the mechanism of the innate immune response in O. furnacalis and provides a theoretical basis for better biological control using microbial agents.

Long term changes (1990-2016) in carabid beetle assemblages (Coleoptera: Carabidae) in protected forests on Dinaric Karst on Mountain Risnjak, CroatiaOriginal article

®eljka JAMBRO©IĆ VLADIĆ, Lucija ©ERIĆ JELASKA

Eur. J. Entomol. 117: 56-67, 2020 | DOI: 10.14411/eje.2020.006

Carabids, as well-known bioindicators, have been used to study the long term changes that have occurred in their communities in the Dinaric Alps. This study involved eight sites in the protected forests of the Risnjak National Park in the years 2015 and 2016 of which three were previously studied in 1990 and 1991. A total of 9, 521 individual ground beetles belonging to 17 genera and 33 species were collected. Species diversity and community composition, including percentages of species grouped according to their habitat preferences, body size, wing morphology, preferred moisture and temperature were used to compare the sites sampled in 1990 and 1991 and resampled in 2015 and 2016. Even though this study was carried out in protected forests within the National Park with minimal anthropogenic pressure and the fact that available climatic data didn't show any significant change in climate over the last 25 years, there was a reduction in the abundance of specialist species and increase in the spread of generalist species. Furthermore, the lower abundance of a mountain specialist and endemic species, Pterostichus variolatus, and the lack of mountain specialists Molops alpestris, Pterostichus unctulatus and Trechus croaticus in the catches indicate the importance of further monitoring of these mountain forest ecosystems and for a well-timed and appropriate conservation approach.

Fine structure of Drosophila larval salivary gland ducts as revealed by laser confocal microscopy and SEMOriginal article

Denisa BEŇOVÁ-LISZEKOVÁ, Milan BEŇO, Robert FARKA©

Eur. J. Entomol. 118: 123-134, 2021 | DOI: 10.14411/eje.2021.013

The functions of the larval salivary glands (SGs) of Drosophila are traditionally associated with the production of a massive secretion during puparium formation; it is exocytosed into a centrally located lumen and subsequently expectorated via ducts, the pharynx and mouth. This so-called proteinaceous glue serves as an adhesive to attach the puparial case to a solid substrate. Great attention has been paid to the secretory cells of SGs, which are famous for their giant polytene chromosomes. However, substantially less attention has been devoted to individual or common ducts that form the most proximal portion of the SG organ via which the glue is released into the pharynx. In the present paper, we describe the organization and fine structure of the taenidia, highly specialized circumferential ring-like extracellular (cuticular) components on the internal side of these tubes. Two chitin-specific probes that have previously been used to recognize taenidia in Drosophila tracheae, Calcofluor White M2R (also known as Fluorescent Brightener 28) and the novel vital fluorescent dye SiR-COOH, show positively stained ductal taenidia in late larval SGs. As seen using scanning electron microscopy (SEM), the interior of the ductal tube contains regular and densely-arranged ridge-like circumferential rings which represent local thickenings of the cuticle in various geometries. The microtubular arrays that optically colocalize with taenidia in both the trachea and SG ducts are specifically and strongly recognized by fluorescently-conjugated colchicine as well as anti-tubulin antibody. In contrast to taenidia in the tracheae, the analogous structures in SG ducts cannot be detected by fluorescently-labeled phalloidin or even actin-GFP fusion protein, suggesting that the ducts lack a cortical network made of filamentous actin. We speculate that these taenidia may serve to reinforce the duct during the secretory processes that SGs undergo during late larval and late prepupal stages.

RNA interference-based characterization of Caspar, DREDD and FADD genes in immune signaling pathways of the red flour beetle, Tribolium castaneum (Coleoptera: Tenebrionidae)Original article

Kakeru YOKOI, Wataru ITO, Daiki KATO, Ken MIURA

Eur. J. Entomol. 119: 23-35, 2022 | DOI: 10.14411/eje.2022.003

We previously demonstrated that two immune signaling pathways, Toll and IMD, were concomitantly activated in the model beetle Tribolium castaneum by challenges to their immune system by several species of microbes, including Gram-positive and -negative bacteria as well as yeast. This contrasts with the Drosophila immune system in which more specific pathway activation depending on the type of microbe is well established. We suggest that the activation of an indiscriminate immune pathway in T. castaneum is due in part to an unselective recognition of pathogen-associated molecular patterns by the extracellular sensing modules of the two pathways. In order to obtain a more detailed understanding of the T. castaneum immune pathway, we investigated whether potential components of the T. castaneum IMD pathway, Caspar, DREDD and FADD, are involved in immune reactions triggered by microbial challenges. A sequence analysis of these three genes with the orthologues of other species, including insects, mouse and human, indicated that T. castaneum Caspar, DREDD and FADD functioned as immune signal transducers, which are usually induced by microbial challenges. However, these genes were not induced by microbial challenges. To establish whether these genes are involved in immune reactions, we used RNA interference-mediated knockdown of these genes to assess the microbial induction levels of the representative read-out antimicrobial peptide genes of the respective classes. The results indicated that these genes encode the canonical constituents of the IMD pathway of this beetle. DREDD and FADD influenced the induction of Toll-dependent antimicrobial peptide genes, providing novel crosstalk points between the two immune pathways, which appears to support indiscriminate pathway activation in T. castaneum. Furthermore, the phenotypes of DREDD or FADD knockdown pupae challenged by the two model bacterial pathogens correlated with AMP gene induction in the respective knockdowns, indicating that these intracellular factors contributed to antibacterial host defenses.

Temperature differences associated with colour do not determine where the acorn ant Temnothorax crassispinus (Hymenoptera: Formicidae) chooses to nestOriginal article

Sławomir MITRUS

Eur. J. Entomol. 118: 46-50, 2021 | DOI: 10.14411/eje.2021.005

Temperature is an important factor for invertebrates. Social insects build nests, which along with their ability to thermoregulate, provide shelter from extreme temperatures. However, for many species of ants the most common method of controlling the temperature inside a nest is to choose a suitable nest site. During a field experiment, the choice of nest site by the acorn ant Temnothorax crassispinus, a species which lives in coniferous and mixed forests, was studied. It typically occupies ephemeral nest sites and can move to a new nest site several times in one season. It was predicted that in early spring, dark coloured nest sites would be warmer and thus more frequently occupied by ant colonies. Contrary to this prediction, no difference was recorded in the frequency with which dark and lighter coloured nests were occupied. However, also in contrast to the prediction, in forest in early spring the difference in temperature inside different coloured nests was small. Thus, other features of nests, e.g., volume of cavity, are probably more important in determining nest site selection by this ant.

Mitochondrial DNA variation of Drosophila obscura (Diptera: Drosophilidae) across EuropeOriginal article

Pavle ERIĆ, Marina STAMENKOVIĆ-RADAK, Milan DRAGIĆEVIĆ, Maaria KANKARE, Megan A. WALLACE, Marija SAVIĆ VESELINOVIĆ, Mihailo JELIĆ

Eur. J. Entomol. 119: 99-110, 2022 | DOI: 10.14411/eje.2022.011

Drosophila obscura is a common fruit fly that inhabits the temperate forests of Europe. While it is abundant in the north compared to other Drosophila, its density decreases southwards, where it is gradually replaced by other Drosophila species. This study describes variation in the mitochondrial Cyt b gene of D. obscura from several European populations. We observed a large number of haplotypes, together with the structuring of genetic variation. Genetic variation is higher in the west where O1 and related divergent haplotypes dominate. In the east, the O2 haplotype is most frequent, together with haplotypes that recently arose from it. In the central part of the species range, both O1 and O2 are equally present, along with many others. These data reveal signs of population expansions that probably happened earlier in the west, and more recently in the east. Though our conclusions are based on only one genetic marker, limiting the power of the analysis, the results imply either postglacial expansion from two unique sources or, more likely, eastwards stepping-stone expansion. This study adds important information on genetic variation and phylogeography to the obscure biology of D. obscura, a species that has the potential to become an interesting model in evolutionary biology and conservation genetics.

Seasonal fluctuations and development of degree-day models for Chilo partellus (Lepidoptera: Crambidae) in maize fields in the Mediterranean regionOriginal article

Tange Denis ACHIRI, Ekrem ATAKAN, Serkan PEHLIVAN

Eur. J. Entomol. 117: 68-75, 2020 | DOI: 10.14411/eje.2020.007

Chilo partellus Swinhoe 1885 (Lepidoptera: Crambidae) is a serious pest of maize in many parts of the world. It was reported for the first time in 2014 in the Mediterranean part of Turkey. Degree-Day (DD) models were developed to predict seasonal dynamics in maize fields using 3-parameter 'Boltzman' and a 4-parameter Logistic regressions. Larval/plant counts were monitored in pesticide-free maize fields in Adana, Turkey from 2017 to 2019. Depending on the year, the first record of C. partellus was between 03-14 May, corresponding to ~ 9-12 DD accumulated from 01 May. There were two main peaks; one in each of the maize growing seasons. The models accurately predicted the phenology of C. partellus with an Adj. R 2 greater than 0.80. The 'Boltzman' regression had lower AICc, ΔAICc and Wі values than the logistic regression. Based on the 'Boltzman' model, 50% of the accumulated larvae/plant count for the first and second generations (peaks) occurred at 80DD and 375DD, 81DD and 413DD, and 54DD and 289DD in 2017, 2018 and 2019, respectively. For the logistic regression model, 50% of the accumulated larvae/plant counts occurred for the first and second generation at 90DD and 362DD, 62DD, and 45DD and 250DD in 2017, 2018, and 2019, respectively. Both these models could play a crucial role in the integrated pest management (IPM) of C. partellus in maize fields in Mediterranean regions.

Using sentinel prey to assess predation pressure from terrestrial predators in water-filled tree holesOriginal article

Martin M. GOSSNER, Elena GAZZEA, Valeriia DIEDUS, Marlotte JONKER, Mykola YAREMCHUK

Eur. J. Entomol. 117: 226-234, 2020 | DOI: 10.14411/eje.2020.024

Tree-related microhabitats are important for forest biodiversity. Water-filled tree holes are one such microhabitat and can be abundant in temperate forests. The arthropod community in this microhabitat not only contribute to forest biodiversity but also provides food for terrestrial predators such as arthropods, small mammals and birds. The extent of the threat of attack from terrestrial predators on insect larvae in this microhabitat, however, is poorly known. To measure predation in this microhabitat, we produced fake prey resembling insect larvae using white plasticine and exposed them at the aquatic-terrestrial habitat interface. We recorded: (1) which predators attacked the fake larvae, (2) the predation probability on the fake larvae after two days and after two weeks and (3) whether predation probability on fake larvae differed between managed and unmanaged forest zones in one of the last primeval beech forests, the Uholka division of the Carpathian Biosphere Reserve in the Ukrainian Carpathians. By addressing these questions, we aimed to quantify the predation pressure of terrestrial predators on insect larvae in tree-holes. The probability that a fake larva in a tree hole was attacked by predators ranged between 25-58% (95% CI) after two days and between 76-96% (95% CI) after two weeks. Overall, the highest attack rates were recorded for small mammals, followed by arthropods and birds. Arthropods took longer to detect potential prey items than small mammals and birds, and they were the only group that showed significant differences in attack rates between forest zones (unmanaged > managed). This study revealed that sentinel prey might be a suitable method for measuring the predation pressure from terrestrial predators on insect larvae in water-filled tree holes.

DNA barcoding reveals long-term speciation processes in subspecies of the Melipona (Michmelia) seminigra complex (Hymenoptera: Apidae)Original article

Izaura Bezerra FRANCINI, João Marcos Guimarães CAPURUCHO, Antônio Saulo Cunha MACHADO, Carlos Gustavo NUNES-SILVA, Jacqueline Da Silva BATISTA, Luciano COSTA, Gislene Almeida CARVALHO-ZILSE

Eur. J. Entomol. 119: 309-317, 2022 | DOI: 10.14411/eje.2022.032

The stingless bee Melipona (Michmelia) seminigra Friese is a polytypic species widely distributed in Brazilian Amazon and Bolivia. Seven subspecies are recognized, four are described, which inhabit mutually exclusive areas in the Amazon basin, although zones of hybridization are recorded. The three other subspecies, despite being recognized by taxonomists are undescribed. Melipona seminigra is a good honey-producer and an important pollinator of native flora and crops. Partial DNA sequence of cytochrome c oxidase subunit 1 (COI) mitochondrial gene (526 bp) was used to identify the four described subspecies of M. seminigra (M. s. abunensis, M. s. merrillae, M. s. pernigra, M. s. seminigra) and two other possible subspecies (M. s. ssp1 and M. s. ssp2). We added public data (sequences of ten other Melipona species) of the same subgenera and carried out phylogenetic analyses. The aim was to evaluate if subspecies in the M. seminigra complex could be delimited using COI and measure the genetic distances between them. Our results revealed that the genetic distances between subspecies of M. seminigra ranged from 0.4 to 2.7% (average 1.80 ± 0.47) and among Melipona species from 0.2 to 2.9% (average 2.13 ± 0.5). The average haplotype diversity was 0.8770 ± 0.0140 and average nucleotide diversity 0.0166 ± 0.0004. Phylogenetic and clustering analysis revealed well delimited clusters for subspecies of M. seminigra and that the inter subspecies divergences are similar to inter species divergence. Our findings indicate that the COI gene can be used for delimiting subspecies of M. seminigra.

Revision of the assassin bug genus Neopirates (Heteroptera: Reduviidae: Peiratinae), with descriptions of two new species from NamibiaOriginal article

Yingqi LIU, Zhuo CHEN, Michael D. WEBB, Wanzhi CAI

Eur. J. Entomol. 117: 343-351, 2020 | DOI: 10.14411/eje.2020.039

The African assassin bug genus Neopirates Miller, 1952, is revised. The type species, N. nyassae Miller, 1952, is redescribed and illustrated; two new species from Namibia, N. bicolor Liu & Cai sp. n. and N. xanthothorax Liu & Cai sp. n. are described and a key is provided to separate the three species of this genus. Sphodrembas fumipennis Swanson, 2019, the type species of Sphodrembas Swanson, 2019, is placed as a junior synonym of N. nyassae, resulting in Sphodrembas becoming a junior synonym of Neopirates. Morphological differences between Neopirates and similar genera and the distribution of Neopirates are briefly discussed.

Six new species of the subgenus Habronychus (Habronychus) (Coleoptera: Cantharidae) from the Oriental region, with key to speciesOriginal article

Shujuan GE, Haoyu LIU, Xingke YANG, Yuxia YANG

Eur. J. Entomol. 119: 201-214, 2022 | DOI: 10.14411/eje.2022.022

Six new species of Habronychus (Habronychus) Wittmer, 1981 are described, including H. (H.) laticeps Y. Yang, Ge & X. Yang, sp. n., H. (H.) honestus Y. Yang, Ge & X. Yang, sp. n., H. (H.) crassatus Y. Yang, Ge & X. Yang, sp. n. and H. (H.) tengchongensis Y. Yang, Ge & X. Yang, sp. n. from China, and H. (H.) longiplatus Y. Yang, Ge & Liu, sp. n. and H. (H.) trianguliceps Y. Yang, Ge & Liu, sp. n. from Vietnam. In addition, a previously known species, H. (H.) parallelicollis (Pic, 1921), is redescribed. The above species are illustrated with habitus photographs, aedeagi, abdominal sternites VIII and internal genitalia of females. Key for identification of the species of this subgenus worldwide is provided.

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