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Results 451 to 480 of 825:

Symbiotic bacteria (Erwinia sp.) in the gut of Frankliniella occidentalis (Thysanoptera: Thripidae) do not affect its ability to transmit tospovirus

Egbert J. DE VRIES, Fennet VAN DE WETERING, Marieke M. VAN DER HOEK, Gerrit JACOBS, Johannes A.J. BREEUWER

Eur. J. Entomol. 109 (2): 261-266, 2012 | DOI: 10.14411/eje.2012.034

Tomato spotted wilt virus (TSWV) is one of the most harmful plant viruses and one of its most important vectors is the western flower thrips [Frankliniella occidentalis Pergande (Thysanoptera: Thripidae)]. Recently, we reported the close association of Erwinia sp. gut bacteria with this species of thrips. The first instar larvae acquire these bacteria from their food source. A high proportion of adult western flower thrips transmit TSWV after acquiring the virus during the first larval stage when there are no bacteria in their gut. A considerably lower proportion of adults that acquire the virus early in the second instar transmit virus and none of those exposed to virus late on in the second instar do so. The highest prevalence and total number of symbiotic bacteria are recorded in the guts of second instar thrips. This leads to the hypothesis that the build up of bacteria in the gut reduces the acquisition of TSWV, resulting in a lower capacity to transmit the virus. To test this hypothesis, the transmission of this virus by symbiotic and aposymbiotic adult thrips of the NL3 population was studied. Comparison of virus transmission by adult thrips, the larvae of which either had or lacked gut bacteria and were exposed to virus in either the first or second instar, revealed no difference in the ability of symbiotic and aposymbiotic adults to transmit this virus. We conclude that virus transmission is not affected by the number of the symbiotic bacteria Erwinia sp. present in the gut of thrips larvae.

The influence of polarized moonlight and collecting distance on the catches of winter moth Operophthera brumata (Lepidoptera: Geometridae) by light traps

László NOWINSZKY, Anikó HIRKA, György CSÓKA, Gergely PETRÁNYI, János PUSKÁS

Eur. J. Entomol. 109 (1): 29-34, 2012 | DOI: 10.14411/eje.2012.005

In this study we examine the relationship between the Lunar Phases and the efficiency of light traps in catching winter moth (Operophthera brumata Linnaeus, 1758). Our calculations are based on data collected by the Hungarian Forestry Light Trap Network at four sites from 1961 to 2008. We also tried to estimate the influence of polarized moonlight and collecting distance, which also depends on moonlight. Our investigations revealed that the catches were the greatest in the First and the Last Quarters, and the lowest at Full Moon. The reason for this is that the proportion of polarized moonlight in the different lunar quarters varies, with the catches highest when the proportion is greatest. Collecting distance has only a minor role.

Survival of ground beetles (Coleoptera: Carabidae) submerged during floods: Field and laboratory studies

Felix N. KOLESNIKOV, Arevik N. KARAMYAN, W. Wyatt HOBACK

Eur. J. Entomol. 109 (1): 71-76, 2012 | DOI: 10.14411/eje.2012.009

Field and laboratory experiments were conducted to assess the time ground beetles (Coleoptera: Carabidae) survive during actual and simulated flood conditions. The effects of three variants of potential flood conditions were tested: (1) beetles trapped on the surface of flood water; (2) beetles trapped in air pockets; (3) submersion of beetles in flood water without access to air. Ground beetles trapped on the surface of water survived more than two weeks (Carabus granulatus - up to 16 days; Oxypselaphus obscurus - up to 22 days). Carabus granulatus in simulated hibernation chambers that had air-pockets also survived for 15 days. The time for which ground beetles submerged without access to air survived differed significantly among species and was affected by season. They survived longest in mid-spring and late-autumn when water temperature is low. In mid-spring, survival times for C. granulatus and Platynus assimilis were 12 days and 9 days, respectively. During late summer and early autumn all species survived for a shorter period of time. In August, at least half of the individuals tested were dead after three days of immersion (water temperature 16-18°C). Removal of both of the elytra of adult of C. granulatus resulted in them surviving immersion for a shorter period, which indicates that air stored in the sub-elytral cavity is used to prolong the period they can survive immersion. The results of these experiments broaden the knowledge of how adult beetles survive seasonal flooding and are able to persist in floodplain habitats.

Parasitism and migration in southern Palaearctic populations of the painted lady butterfly, Vanessa cardui (Lepidoptera: Nymphalidae)

Constantí STEFANESCU, Richard R. ASKEW, Jordi CORBERA, Mark R. SHAW

Eur. J. Entomol. 109 (1): 85-94, 2012 | DOI: 10.14411/eje.2012.011

The painted lady butterfly (Vanessa cardui) (Lepidoptera: Nymphalidae: Nymphalinae) is well known for its seasonal long-distance migrations and for its dramatic population fluctuations between years. Although parasitism has occasionally been noted as an important mortality factor for this butterfly, no comprehensive study has quantified and compared its parasitoid complexes in different geographical areas or seasons. In 2009, a year when this butterfly was extraordinarily abundant in the western Palaearctic, we assessed the spatial and temporal variation in larval parasitism in central Morocco (late winter and autumn) and north-east Spain (spring and late summer). The primary parasitoids in the complexes comprised a few relatively specialized koinobionts that are a regular and important mortality factor in the host populations. However, there was a strong seasonal variation in the level of parasitism. In Spain percentage parasitism was more than four times higher in late summer than in spring (77.3% vs. 18%), while in Morocco it was five times higher by the end of winter than in the autumn (66.2% vs. 13.2%). In both regions the build up of parasitoid populations occurred after V. cardui had bred in the same general area over successive generations, and this may represent a selective force favouring seasonal migration to enemy-free space.

Multicoloniality in the highly polygynous ant Crematogaster pygmaea (Formicidae: Myrmicinae)

Rachid HAMIDI, Gabriel DEBOUT, Ana HEREDIA, Denis FOURNIER, Yves QUINET, Jean-Christophe De BISEAU

Eur. J. Entomol. 109 (1): 95-102, 2012 | DOI: 10.14411/eje.2012.012

In social insects, the high variability in the number of queens per colony raises fundamental questions about the evolution of altruism. It is hypothesized, for instance, that nestmate recognition should be less efficient in polygynous than in monogynous colonies because the presence of several breeders increases the diversity of genetically determined recognition cues, leading to a less specific colonial signature. Recent studies, however, have shown that the link between the number of queens in a colony and the recognition abilities of its members is more complex than previously suggested. Here, we studied intraspecific aggression, diversity of potential recognition cues and genetic structure of colonies in the highly polygynous ant Crematogaster pygmaea. Our results reveal that workers of this species are clearly aggressive towards non-nestmates in field experiments but not in more artificial bioassays conducted in Petri dishes, underscoring the importance of context-dependent aspects of the assessment of nestmate recognition. Behavioural, genetic and chemical data show that C. pygmaea is a multicolonial species, forming spatially restricted and well-defined entities. Therefore, the postulated negative correlation between recognition ability of workers and queen number in a colony is not supported by the results of this study.

Changes in the calling behaviour of female Spodoptera littoralis (Lepidoptera: Noctuidae) as a function of body weight and adult feeding

Medhat M. SADEK

Eur. J. Entomol. 109 (1): 103-109, 2012 | DOI: 10.14411/eje.2012.013

Because nutrients accrued during larval stages represent the major limiting factor for egg production, the use of adult feeding to enhance the reproductive output in moths is considered to be largely weight-dependent. It is hypothesized, however, that feeding by adults could be adaptive and an effective means of increasing their reproductive success. In order to test this, the calling behaviour of Spodoptera littoralis females that differed in body weight and whether they had fed or not were recorded. Two experiments were carried out. In the first, the calling behaviour of food-deprived females of different body weights was recorded. A strong positive correlation was found between body weight at emergence and the total duration of calling of females on the second to the fifth night after emergence. In the second experiment, groups of female moths that varied in body weight were given access to water or sucrose. Feeding on sucrose significantly reduced the pre-calling period and increased the total time spent calling on the six nights after emergence. The increase in time spent calling associated with ingesting sucrose were proportionately similar for both small and large females, implying that feeding by adults can result in an increase in the time spent calling by moths irrespective of larval nutritional status. Female longevity was also correlated with moth weight at emergence and/or sucrose availability. It is concluded that it is advantageous for female S. littoralis to be large and/or have access to sucrose-rich food in the adult stage as they can spend more time attracting a mate, which increases their chances of mating in early adult life, and their longer adult life may indirectly result in an increase in fecundity.

Effect of the size of the pupae, adult diet, oviposition substrate and adult population density on egg production in Musca domestica (Diptera: Muscidae)

Berta PASTOR, Helena ČIČKOVÁ, Milan KOZÁNEK, Anabel MARTÍNEZ-SÁNCHEZ, Peter TAKÁČ, Santos ROJO

Eur. J. Entomol. 108 (4): 587-596, 2011 | DOI: 10.14411/eje.2011.076

In order to enhance the mass production of the house fly, Musca domestica, five aspects of its oviposition biology were analyzed. Oviposition substrate and the manner of its presentation, the composition of the diet of the adults, size of the pupae and numbers of flies in a cage were identified as critical. Females preferred to lay eggs on a substrate which was presented within a shelter and with increased linear edges against which the flies could oviposit. Different types of oviposition substrate resulted in comparable yields of eggs. The presence of an oviposition attractant (ammonia) in the manure was found to have a potentially positive effect on female fecundity. Egg yield increased when two protein sources (yeast and milk) were included in the adult diet. However, flies fed a mixture of sugar and yeast laid over 50% fewer eggs than those fed the same proportion of sugar and milk. The fecundity of flies decreased with increase in the number of flies per cage, but the highest total number of eggs per cage was obtained when the flies were most crowded (14.2 cm3 per fly). The size of the pupae did not significantly affect egg production.

Abundance and species richness of overwintering ground beetles (Coleoptera: Carabidae) are higher in the edge than in the centre of a woodlot

Anthony ROUME, Annie OUIN, Laurent RAISON, Marc DECONCHAT

Eur. J. Entomol. 108 (4): 615-622, 2011 | DOI: 10.14411/eje.2011.080

Semi-natural habitats are key components of rural landscapes because they shelter a significant number of overwintering arthropods that are beneficial to agriculture. However, woodlots are semi-natural habitats with high patch-level heterogeneity and this aspect has been poorly studied. The purpose of this study was to determine the influence of woodlot heterogeneity on overwintering ground beetles. Woodlot heterogeneity was characterized in terms of distance from the woodlot boundary and date of the most recent logging operation. We used emergence traps to quantify the population density of ground beetles that overwintered in the different parts of the woodlot. In woodlot edges the densities and species richness of ground beetles were significantly higher than in the rest of the woodlot. Ground beetles that are active in crop fields overwintered in the edges but not in the inner zone of the woodlot. Species assemblages of ground beetles overwintering in the edges were highly diverse. The date of the most recent logging operation did not explain the distribution of ground beetles that overwintered in the woodlot. Our results show that woodlots, and in particular their edges, are used as a winter shelter by ground beetles that spend part of their life in crops, which potentially favours biological control in adjacent crop fields.

The parasitoid species complex associated with sexual and parthenogenetic Naryciinae (Lepidoptera: Psychidae): Integrating ecological and molecular analyses

Jelmer A. ELZINGA, Kees ZWAKHALS, Johanna MAPPES, Alessandro GRAPPUTO

Eur. J. Entomol. 108 (4): 635-650, 2011 | DOI: 10.14411/eje.2011.082

This study describes the parasitoid species complex associated with seven closely related species of sexual (Siederia rupicollella, S. listerella, Dahlica lazuri, D. charlottae and D. lichenella) and parthenogenetic (Dahlica fennicella and D. triquetrella) Naryciinae (Lepidoptera: Psychidae) in Central Finland. A thorough ecological analysis of all the species of parasitoids recorded was combined with analyses of molecular data. Mitochondrial and nuclear DNA data were obtained from all the species in order to (1) detect cryptic species associated with host specialization, (2) assign undescribed males to females, and (3) verify the morphological identification of closely related species. A DNA barcoding technique was employed to identify host species from parasitized larval remains. By sampling more than 10,000 host larvae, of which 25.7% were parasitized, nine parasitoid species were identified morphologically, including both koinobionts (Ichneumonidae: Diadegma incompletum, Macrus parvulus, Trachyarus borealis, T. solyanikovi, T. fuscipes, T. brevipennis and Braconidae: Meteorus affinis) and idiobionts (Ichneumonidae: Orthizema flavicorne, Gelis fuscicornis). Ecological characteristics such as time and mode of host attack, time of emergence and level of specialization differed widely. The results show that differences in parasitoid biology need to be taken into account when studying differences in percentage parasitism of sexual and parthenogenetic Naryciinae. The molecular data revealed that one parasitoid species M. parvulus may consist of two cryptic forms associated with the sexual and parthenogenetic hosts, respectively. The data further establishes that T. brevipennis and some T. fuscipes are in fact morphotypes of one species. The large variation in mitochondrial DNA within species and its inconsistency with nuclear DNA demonstrate that current species and genus delimitation is inadequate in the Trachyarus species group. Our study shows that it is essential to use DNA barcoding methods when investigating host-parasitoid complexes.

Relationship between the development of Simulium maculatum (Diptera: Simuliidae) and the thermal regime

Rasa BERNOTIENĖ, Galina BARTKEVIČIENĖ

Eur. J. Entomol. 108 (3): 397-402, 2011

Warmer temperatures in the past 30 years have significantly influenced the seasonal development of insects throughout Europe. As a result of the outbreaks of black flies that have occurred in southeastern Lithuania since the 1970s it is hypothesized that this increase in black fly activity is due to the change in climate. To test this hypothesis the development of Simulium maculatum Meigen under different conditions was determined. This revealed that the time of hatching of S. maculatum eggs in Lithuania was influenced by winter air temperatures, especially those in March. Pupation in S. maculatum is associated with the increase in air and water temperatures that occur at the end of April and in May. The emergence of S. maculatum black flies occurs most often in May. At a water temperature of 13.2°C (1999), S. maculatum took 42 days to develop and half this time (21 days) when the water temperature was 18.8°C (2005). The number of black flies that emerged each year was determined by air temperature but unaffected by rainfall in June (either per month or per ten-day period).

How to increase the value of urban areas for butterfly conservation? A lesson from Prague nature reserves and parks

Martin KONVICKA, Tomas KADLEC

Eur. J. Entomol. 108 (2): 219-229, 2011 | DOI: 10.14411/eje.2011.030

Cities contain only a low representation of natural and semi-natural habitats, existing in fragments surrounded by built-up areas. In 2003-2004, we surveyed butterflies and Zygaenidae moths in 21 reserves and 4 parks within the city of Prague, Czech Republic, situated from the periphery to city centre. A total of 85 species (47% of the Czech fauna of the study groups) was detected, 22 of them being of conservation concern. Ordination analyses of the local assemblages revealed that the richest sites were large, situated far from the city centre, on alkaline bedrocks, south- to southwest oriented, and hosting high numbers of vegetation types and vascular plant species. We then used generalised linear models to fit responses of individual species to the main ordination gradient, corresponding to increasing urbanisation. Out of 60 species that met criteria for the modelling, none responded positively to urbanisation. Twenty displayed negative linear response; these urban avoiders contained a surplus of mesophilous species presumably preferring rural landscapes. Further 29 species (suburban adaptable) responded in domed manners, peaking at the city periphery. Prevailing among them were xerophilous specialists inhabiting large grassland reserves at the Prague outskirts. Finally, eleven urban tolerant species did not respond to urbanisation at all, containing three highly mobile species, three xerothermophilous specialists, and five species utilising shrubs or trees and finding suitable conditions even in urban parks. Suburban adaptable butterflies apparently benefit from such suburban environments as gardens, road or railway verges, collectively increasing the connectivity of remnants of seminatural habitats. The fact that arboreal species persist even in urban parks, whereas common grassland species are absent there, implies that the quality of urban habitats might be increased by a more sensitive management of urban green spaces, such as leaving aside small temporary fallows or adapting lawns mowing schemes.

Demography of adults of the Marsh fritillary butterfly, Euphydryas aurinia (Lepidoptera: Nymphalidae) in the Czech Republic: Patterns across sites and seasons

Kamil ZIMMERMANN, Pavla BLAZKOVA, Oldrich CIZEK, Zdenek FRIC, Vladimir HULA, Pavel KEPKA, David NOVOTNY, Irena SLAMOVA, Martin KONVICKA

Eur. J. Entomol. 108 (2): 243-254, 2011 | DOI: 10.14411/eje.2011.033

The Marsh fritillary (Euphydryas aurinia) (Lepidoptera: Nymphalidae) has declined across Europe, including the Czech Republic. Current conservation strategies rely on prevention of habitat loss and degradation, and increase in habitat quality and connectivity via promoting traditional grassland management. The population structure and adult demography parameters of a single population was investigated for eight years (single system), and of all the known Czech populations (multiple populations) for a single year, using mark-recapture. There was substantial variation in the patterns of adult demography, both among years in the single system and among the multiple populations in a single year. In the single system, the date of the first flight of an adult varied by 18 days over the 8 years and total annual numbers varied with a coefficient of variation of 0.40 (females fluctuating more than males). The average density was ca 80 adults/ha. The population size displayed density-dependence, i.e. decreased following years with high adult numbers, with an equilibrium density of 90 individuals/ha. The average density of the multiple populations was ca 120 individuals/ha. The estimated total population for the Czech Republic was 25,000 individuals (17,000 males / 8,000 females) in 2007, which does not indicate an imminent threat of extinction. The regional persistence of E. aurinia is likely to depend on re-colonisation of temporarily vacant sites by dispersing individuals, facilitated by local shifts in adult flight phenology to that better adapted to local conditions.

Biology of the conifer needle scale, Nuculaspis abietis (Hemiptera: Diaspididae), in northern Iran and parasitism by Aspidiotiphagus citrinus (Hymenoptera: Aphelinidae)

Arash RASEKH, J.P. MICHAUD, Hassan BARIMANI VARANDI

Eur. J. Entomol. 108 (1): 79-85, 2011 | DOI: 10.14411/eje.2011.010

The conifer needle scale, Nuculaspis abietis (Schrank) emerged as an important pest of conifers in the Kelardasht region of Mazandaran province, Iran, in the late 1990's. This pest feeds on conifer needles and twigs causing needle drop and branch desiccation. Its discovery in Kelardasht in Mazandaran Province necessitated a local quarantine of conifers in the genera Picea, Abies, and Pinus. We studied the life history and ecology of this scale on Norway spruce, Picea abies, under laboratory and natural field conditions. The complete life cycle of females required 206.4 ± 5.7 days in the laboratory (25 ± 1°C, 65-75% RH, 14L : 10D) and 315.7 ± 9.3 days under field conditions. In Kelardasht, numbers of adult males and females peaked in mid-June and early May, respectively, and numbers of first and second instar nymphs in mid-July and early September. Lifetime fecundity was estimated to be 57.3 ± 5.1 eggs and 54.0 ± 4.4 nymphs per female under laboratory conditions. The sex ratio ranged from 59% female for second instar nymphs to 71% female for adults. Aspidiotiphagus citrinus (Crawford) (Hymenoptera: Aphelinidae) was found naturally parasitizing the scale and overwintering in the larval stage on second instar nymphs. First generation adult wasps emerged in spring from overwintered second instar nymphs to parasitize 64.75% of first instar scales. Second generation wasps emerged from early September to mid-October and parasitized 19.75% of second instar scales, for a cumulative parasitism rate of 84.5%.

Increasing patch area, proximity of human settlement and larval food plants positively affect the occurrence and local population size of the habitat specialist butterfly Polyommatus coridon (Lepidoptera: Lycaenidae) in fragmented calcareous grasslands

Zuzanna M. ROSIN, Piotr SKÓRKA, Magdalena LENDA, Dawid MORON, Tim H. SPARKS, Piotr TRYJANOWSKI

Eur. J. Entomol. 108 (1): 99-106, 2011 | DOI: 10.14411/eje.2011.013

Which factors influence the occurrence, population size and density of species in fragmented habitat patches are key questions in population and conservation ecology. Metapopulation theory predicts that larger and less isolated habitat patches should positively influence species occurrence and population size. However, recent studies have shown that habitat quality, human activity and permeability of the landscape surrounding habitat patches may be also important. In this paper we test the relative effects of habitat patch characteristics, human settlement and landscape permeability on the occurrence, local population size and density of the Chalk-hill Blue Polyommatus coridon a charismatic butterfly inhabiting calcareous grasslands in a fragmented landscape in southern Poland. Patch occupancy rate (corrected for the butterfly detection probability) was 0.45. Habitat patch area, proximity of human settlement and cover of larval food plants positively affected occurrence of the Chalk-hill Blue. Local population size of the Chalk-hill Blue was positively affected by patch area and proximity of human settlement, and negatively by patch isolation. Local density was higher in patches located close to human settlement. Our study is one of the few showing a positive effect of human settlement on a grassland specialist butterfly although the mechanism hidden behind this phenomenon is unknown and requires further examination. In order to maintain local populations of the Chalk-hill Blue in southern Poland, conservation action should be focused on large, closely connected calcareous grasslands. Moreover, extensive management of this habitat should be maintained by local inhabitants who are better placed to undertake such work.

Highly polymorphic di- and trinucleotide microsatellite markers for the grapevine yellows disease vector Hyalesthes obsoletus (Auchenorrhyncha: Cixiidae)

Miriam IMO, Julia LÜNEBURG, Thomas HANKELN, Alfred SEITZ, Jes JOHANNESEN

Eur. J. Entomol. 108 (1): 161-163, 2011 | DOI: 10.14411/eje.2011.019

Seven polymorphic microsatellite loci were developed for the planthopper Hyalesthes obsoletus, vector of stolbur 16SrXII-A phytoplasma. The loci have di- or trinucleotide repeat motifs and are highly variable with 10 to 22 alleles per locus. Observed heterozygosity ranged from 0.278 to 0.950 for the 78 individuals genotyped. One locus is sex-linked. No linkage between loci was found. All loci amplified consistently among phylogeographic as well as host-plant related samples and proved highly informative for population genetic studies.

Parental age at mating affects reproductive attributes of the aphidophagous ladybird beetle, Coelophora saucia (Coleoptera: Coccinellidae)

OMKAR, Satyendra K. SINGH, Geetanjali MISHRA

Eur. J. Entomol. 107 (3): 341-347, 2010 | DOI: 10.14411/eje.2010.043

Ageing and its affect on life attributes have not been widely explored in ladybirds. The present study investigates the influence of female and male age at mating on the reproductive attributes of the ladybird beetle, Coelophora saucia (Mulsant). All reproductive attributes, viz. fecundity, percentage egg hatch, pre-oviposition, oviposition and post-oviposition periods were found to be influenced by the ages of both females and males at mating. This is unlike the results of previous studies on ladybirds, where male age was found to influence only percentage egg hatch. The influence of male age at mating on fecundity and reproductive periods is probably due to age influenced variation in seminal proteins, which influence fecundity and when the eggs are laid.

Artificial diet for two flat-headed borers, Capnodis spp. (Coleoptera: Buprestidae)

Galina GINDIN, Tatiana KUZNETSOVA, Alexei PROTASOV, Shaul Ben YEHUDA, Zvi MENDEL

Eur. J. Entomol. 106 (4): 573-581, 2009 | DOI: 10.14411/eje.2009.072

The main objective was to develop an artificial diet for two flat-headed borers, Capnodis tenebrionis L. and C. carbonaria Klug. (Coleoptera: Buprestidae), which are severe pests of stonefruit plantations in the Mediterranean basin. The effect of proteins from various sources, percentage of cortex tissue in the diet and diet structure on larval growth and survival were investigated. The most successful diet contained 2.8% casein and 4.6% dry brewer's yeast as the protein source. For complete larval development and successful pupation it is essential to include cortex tissue from the host plant in the diet. Mean larval development time was shortened by 10-12 days when reared on a diet containing 20% cortex tissue compared with rearing on diet containing 10% cortex tissue. Two different diet structures were required, a viscous matrix for the first and second instar larvae and drier crumbly diet, which allows the larvae to move within the diet, for older larvae. At 28°C on the artificial diet C. tenebrionis and C. carbonaria completed their development in 2-2.5 months compared to the 6-11 months recorded in Israeli orchards. C. tenebrionis successfully completed two generations on the artificial diet.

Glutathione S-transferases from the larval gut of the silkworm Bombyx mori: cDNA cloning, gene structure, expression and distribution

Zhong Zheng GUI, Bo Yeon KIM, Kwang Sik LEE, Ya Dong WEI, Xijie GUO, Hung Dae SOHN, Byung Rae JIN

Eur. J. Entomol. 105 (4): 567-574, 2008

Two glutathione S-transferase (GST) cDNAs, GSTD2 and GSTS2, were cloned from the silkworm Bombyx mori. The B. mori GSTD2 (BmGSTD2) gene spans 4371 bp and consists of four introns and five exons that encode 222 amino acid residues. The deduced amino acid sequence of BmGSTD2 showed 58% protein sequence identity to the Delta-class GST of Maduca sexta. The B. mori GSTS2 (BmGSTS2) gene spans 3470 bp and consists of three introns and four exons that encode 206 amino acid residues. The deduced amino acid sequence of BmGSTS2 revealed 67%, 63%, and 61% protein sequence identities to the Sigma-class GSTs from B. mori, Platynota idaeusalis, and M. sexta, respectively. The BmGSTD2 and BmGSTS2 cDNAs were expressed as 25 kDa and 23 kDa polypeptides, respectively, in baculovirus-infected insect Sf9 cells. Northern blot and Western blot analyses showed that BmGSTD2 and BmGSTS2 were specifically expressed in three gut regions, indicating that the gut is the prime site for BmGSTD2 and BmGSTS2 synthesis in B. mori larvae.

Myrmica sabuleti (Hymenoptera: Formicidae) not necessary for the survival of the population of Phengaris (Maculinea) arion (Lepidoptera: Lycaenidae) in eastern Poland: Lower host-ant specificity or evidence for geographical variation of an endangered social parasite?

Marcin SIELEZNIEW, Anna M. STANKIEWICZ

Eur. J. Entomol. 105 (4): 637-641, 2008

Larvae and pupae of the obligatorily myrmecophilous Phengaris (Maculinea) arion were found for the first time in nests of Myrmica rugulosa, M. hellenica and M. schencki at a site in eastern Poland. M. sabuleti, commonly considered as a major host of the butterfly and whose abundance is vital for the survival of P. arion populations, was shown to be very rare and not used. Estimated mean density of Myrmica nests was very low, which suggests that relatively vast areas are necessary to support a viable population of P. arion in similar sandy habitats. This may explain the decline and rarity of the butterfly in the whole region, even though its relationships with ants seem not to be very specific there.

Orthopteran communities in the conifer-broadleaved woodland zone of the Russian Far East

Thomas FARTMANN, Martin BEHRENS, Holger LORITZ

Eur. J. Entomol. 105 (4): 673-680, 2008

We investigate orthopteran communities in the natural landscape of the Russian Far East and compare the habitat requirements of the species with those of the same or closely related species found in the largely agricultural landscape of central Europe. The study area is the 1,200 km2 Lazovsky State Nature Reserve (Primorsky region, southern Russian Far East) 200 km east of Vladivostok in the southern spurs of the Sikhote-Alin Mountains (134°E/43°N). The abundance of Orthoptera was recorded in August and September 2001 based on the number present in 20 randomly placed 1 m2 quadrates per site. For each plot (i) the number of species of Orthoptera, (ii) absolute species abundance and (iii) fifteen environmental parameters characterising habitat structure and microclimate were recorded. Canonical correspondence analysis (CCA) was used first to determine whether the Orthoptera occur in ecologically coherent groups, and second, to assess their association with habitat characteristics. In addition, the number of species and individuals in natural and semi-natural habitats were compared using a t test. A total of 899 individuals of 31 different species were captured, with numbers ranging between 2 and 13 species per plot. Species diversity was higher in semi-natural habitats than natural habitats. There was a similar but non-significant pattern in species density. Ordination analysis indicated four orthopteran communities, which were clearly separable along a moisture and vegetation density gradient. The natural sites in the woodland area of the Lazovsky Zapovednik are characterized by species-poor and low-density orthopteran assemblages compared to the semi-natural sites. But, the natural sites have a higher diversity of habitat specialists. Our findings corroborate the hypothesis that intermediate habitat disturbance levels support particularly species-rich animal communities at high densities. Under such regimes, orthopterans presumably mostly profit from the high diversity in plant species, which generates great structural and microclimatic heterogeneity.

Origin of Jordanian honeybees Apis mellifera (Hymenoptera: Apidae) using amplified mitochondrial DNA

Shahera ZAITOUN, Dhia S. HASSAWI, Wesam SHAHROUR

Eur. J. Entomol. 105 (1): 41-44, 2008 | DOI: 10.14411/eje.2008.005

The honeybee (Apis mellifera L.) has a large number of geographic subspecies distributed across Europe, Africa and Asia, many of which have been described. This identification is important for bee breeding and preserving honeybee biodiversity. To investigate the origin of Jordanian honeybees, 32 samples collected from different locations in Jordan were analyzed using four different enzyme systems: Bg/II site in cytochrome oxidase b (Cytb), EcoRI site in large ribosomal (lsRNA) subunit, XbaI site in cytochrome c oxidase I (COI) subunit and HinCII site in cytochrome c oxidase I (COI) subunit. The first three enzymes were found to be polymorphic. The DNA banding pattern analyses revealed that Jordanian honeybees belong to the East Mediterranean and Middle Eastern mitochondrial lineages.

Genetic variation in East-Adriatic populations of the Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae), inferred from NADH5 and COI sequence variability

Toni ®ITKO, Ana KOVAČIĆ, Yves DESDEVISES, Jasna PUIZINA

Eur. J. Entomol. 108 (4): 501-508, 2011 | DOI: 10.14411/eje.2011.065

In the last few decades, Aedes albopictus (Skuse) (Diptera: Culicidae) (= Stegomyia albopicta), the so-called "Asian tiger mosquito", has spread from its native range in southeast Asia to Africa, the Middle East, Europe, the Americas, and Pacific islands. The spread of this species poses a risk to human health as it is considered to be one of the main vectors of dengue and other arboviruses. Aedes albopictus was reported in Croatia in 2004, thereafter it was discovered at several coastal localities in 2005 and to date it has spread to most coastal areas and islands in Croatia. Here we investigate the genetic variability of A. albopictus based on 39 individuals collected during the summer of 2009 along the East-Adriatic coast and islands of Croatia and Montenegro and using two mitochondrial molecular markers: cytochrome oxidase I (COI) and NADH dehydrogenase 5 (ND5). We identified a single ND5 haplotype, corresponding to the previously reported and worldwide-distributed haplotype H3. The COI marker was more variable and we identified four COI haplotypes. In order to identify the geographic origin of the populations that colonized Croatia, we performed phylogenetic analyses of ND5 and COI haplotypes in Croatian populations and other A. albopictus populations retrieved from the GenBank. The phylogenetic tree based on ND5 haplotypes revealed two well supported clades where the unique Croatian ND5 haplotype clustered with the majority of haplotypes originating from South-Asia, America, Europe, and Africa. Another smaller cluster consisted of only Brazilian haplotypes. The phylogenetic tree and haplotype network that resulted from the COI analysis also indicates that the three Croatian COI haplotypes cluster with European and American haplotypes. However the fourth Croatian COI haplotype was the only European haplotype that occurred in a separate clade (group) with Indian, South-Asian, and Brazilian haplotypes. This data suggests there have been several independent introduction events in Croatia.

Comparative analysis of the location of rDNA in the Palaearctic bushcricket genus Isophya (Orthoptera: Tettigoniidae: Phaneropterinae)

Beata GRZYWACZ, Anna MARYAŃSKA-NADACHOWSKA, Dragan P. CHOBANOV, Tatjana KARAMYSHEVA, Elżbieta WARCHAŁOWSKA-¦LIWA

Eur. J. Entomol. 108 (4): 509-517, 2011 | DOI: 10.14411/eje.2011.066

The present study focused on the evolution of the karyotype in 21 taxa of the genus Isophya, which was done by mapping the location on the chromosomes of ribosomal RNA (rRNA) coding genes using fluorescence in situ hybridization (FISH) with an 18S rDNA probe and using silver staining (AgNO3) to evaluate the activity of major rDNA clusters. Since the chromosome number and sex determination do not vary in this genus, the above markers were used in a detailed comparison of the cytogenetic features of species of Isophya. The species analyzed were placed into three groups based on the location of rDNA on their chromosomes: (1) rDNA-FISH signals only on the two long pairs of autosomes, (2) rDNA-FISH signals on one long and one short pair of autosomes, and (3) rDNA-FISH signals on three to five different sized pairs of autosomes. These groupings partly correspond to the morphological groupings proposed in earlier studies. One long pair of autosomes frequently carried rDNA in all the Isophya species and probably is a plesiomorphic character for these taxa. The cytogenetic mapping revealed great variability among Isophya species in the chromosomal location of major rDNA clusters. Our results suggest that the observed variation in the number of rDNA clusters can be an important species-group specific phylogenetic marker. Analysis of 18S rDNA hybridization signals showed that the evolutionary dynamics of rDNA in this genus is remarkably high and accompanied by changes in the structure of chromosomes bearing rDNA at an inter- and intra-specific level. The telomeric sequence (TTAGG)n hybridized with the termini of most of chromosomes, however, some chromosome ends lacked signals probably due to a low copy number of telomeric repeats.

One variable species or multiple cryptic? Mitochondrial phylogeny of Central and North American Chlosyne lacinia (Lepidoptera: Nymphalidae)

Timothy C. BONEBRAKE, Ward B. WATT, Alejandro PEREZ, Carol L. BOGGS

Eur. J. Entomol. 108 (4): 529-535, 2011 | DOI: 10.14411/eje.2011.068

Recent efforts to catalogue global biodiversity using genetic techniques have uncovered a number of "cryptic" species within morphologically similar populations that had previously been identified as single species. Chlosyne lacinia (Lepidoptera: Nymphalidae), with a range extending from the Southwest U.S. to South America, is one of the most phenotypically variable and broadly distributed butterfly species in the New World. We sampled populations of C. lacinia in two temperate locations (California and Arizona) and one tropical location (El Salvador) to determine if cryptic species were present at this scale (temperate vs. tropical). We examined mtDNA sequence variation in COI, COII, the intervening tRNA (Leucine-2), 16S, 12S and an additional intervening tRNA (Valine), accounting for approximately 20% of the mitochondrial genome (3479 bp). Among all C. lacinia individuals, sequence divergence did not exceed 0.0084 compared to a 0.06 estimated divergence between C. lacinia and congener C. leanira. We also found subclade structure which did not clearly correspond to geography or subspecific designation. Though the mitochondrial phylogeny suggests a complex evolutionary history and biogeography, we demonstrate that one C. lacinia species is distributed throughout North and Central America spanning a diverse set of temperate and tropical habitats.

Divergent patterns in the mitochondrial and nuclear diversity of the specialized butterfly Plebejus argus (Lepidoptera: Lycaenidae)

Marcin SIELEZNIEW, Donata PONIKWICKA-TYSZKO, Miroslaw RATKIEWICZ, Izabela DZIEKANSKA, Agata KOSTRO-AMBROZIAK, Robert RUTKOWSKI

Eur. J. Entomol. 108 (4): 537-545, 2011 | DOI: 10.14411/eje.2011.069

Plebejus argus is a model species for studying the biology, population ecology and genetics of butterflies. It is patchily distributed throughout most of its European range and considered to be sedentary. Habitats of the butterfly have to encompass two vital larval-resources, i.e. specific food plants and ants, since caterpillars are obligatorily myrmecophilous. The genetic structure of nine P. argus populations (85 individuals) was studied at an intermediate geographical scale (Eastern Poland, diameter of about 400 km) using two kinds of molecular markers i.e. COI (mtDNA) and EF-1α (nuclear gene). Both markers were highly variable with as many as 16 haplotypes and 39 alleles, respectively. Great genetic differentiation in the COI gene was detected (overall FST = 0.411, P < 0.001) but little genetic differentiation in the EF-1α gene (FST = 0.021, P < 0.001). The number of COI haplotypes (ranging from one to seven) and their distribution varied considerably among P. argus populations. The possibility that this heterogeneity was related to Wolbachia was excluded as this endoparasitic bacterium was not detected in samples from any of the populations studied. PCA and SAMOVA analyses divided the sampled populations into two or three groups, which could indicate different colonization routes. Moreover, the differences in genetic differentiation with respect to mtDNA and nuclear markers may suggest male-biased dispersal of P. argus at a larger scale. The hypothesis that females are philopatric is consistent with direct observations of the restricted colonization abilities of the butterfly, while the relatively homogeneous genetic structure revealed by previous allozyme studies in some areas might be explained by the possible higher mobility of males.

Molecular phylogenetic analysis of a scale insect (Drosicha mangiferae; Hemiptera: Monophlebidae) infesting mango orchards in Pakistan

Muhammad ASHFAQ, Jehan ARA, Ali Raza NOOR, Paul D.N. HEBERT, Shahid MANSOOR

Eur. J. Entomol. 108 (4): 553-559, 2011 | DOI: 10.14411/eje.2011.071

Mango orchards in Pakistan are attacked by the scale insect, Drosicha mangiferae (Hemiptera: Monophlebidae), commonly called the "mango mealybug". This insect is univoltine, active from December through May and targets multiple host plants. We used DNA nucleotide sequences to characterize and determine the phylogenetic status of D. mangiferae. Mango mealybugs were collected from several tree species from different localities and patterns of phylogenetic and genetic diversity were examined at both nuclear (18S, ITS1) and mitochondrial (COI) genes. Phylogenetic analysis confirms that the mango mealybug belongs to the family Monophlebidae. Minor genetic differences in both the ITS1 and the COI barcode region were noted among D. mangiferae collected from different geographic localities. These genetic differences revealed the existence of two genotypes of D. mangiferae that are region specific but not host-specific.

Chilocorus renipustulatus (Coleoptera: Coccinellidae) dominates predatory ladybird assemblages on Sorbus aucuparia (Rosales: Rosaceae)

Emanuel KULA, Oldřich NEDVĚD

Eur. J. Entomol. 108 (4): 603-608, 2011 | DOI: 10.14411/eje.2011.078

Fourteen predatory species of ladybirds (Coleoptera: Coccinellidae) were collected from May to October 2008 from mountain ash (Sorbus aucuparia) infested with the scale insect Chionaspis salicis at 31 localities in the Ore Mountains, northern Bohemia, Czech Republic. Chilocorus renipustulatus, usually a rare species, made up 85% of the individuals collected (1690). Other abundant species were Coccinella septempunctata, Calvia quatuordecimguttata, Adalia bipunctata and Adalia decempunctata. The invasive alien Harmonia axyridis was present but made up less than one per cent of the individuals collected. Niche overlap between pairs of ladybird species measured in terms of the coefficient of community, Morisita's index and cluster analysis showed that microhabitat preferences were similar and hence the possibility of competition was high in two pairs of congeneric species (Chilocorus and Calvia). Larvae of Ch. renipustulatus were abundant from mid-June through August and were still present in October.

Landscape structure affects activity density, body size and fecundity of Pardosa wolf spiders (Araneae: Lycosidae) in winter oilseed rape

Thomas DRAPELA, Thomas FRANK, Xaver HEER, Dietmar MOSER, Johann G. ZALLER

Eur. J. Entomol. 108 (4): 609-614, 2011 | DOI: 10.14411/eje.2011.079

In large parts of Europe Pardosa spp. (Lycosidae) are among the most abundant wolf spiders in arable fields and potentially important natural control agents of pests. We studied the influence of landscape factors on activity density, adult body size and fecundity of P. agrestis in 29 winter oilseed rape fields (Brassica napus L.) in Eastern Austria using pitfall traps. Landscape data were obtained for eight circular landscape sections around each field (radii 250-2000 m). Multivariate regression models were used to analyze the data. Activity density was highest when the length of strips of grassy road-sides in the surroundings was highest and distance to the next grassy fallow lowest. Body size was negatively related to activity density and to the length of road-side strips and positively to woody areas in the vicinity of the fields. Clutch size was unrelated to any of the landscape factors tested but was positively correlated with female body size. Woody areas and grassy fallow in the close vicinity of the fields had a positive influence on number of offspring per female and total number of offspring. These results indicate that various non-crop components in the landscape surrounding oilseed rape fields can specifically influence the activity density and fitness-related traits of P. agrestis in crops. The possible role of Pardosa spp. in natural pest control is discussed.

Altitudinal trends in the phenology of butterflies in a mountainous area in central Spain

Juan Ignacio De ARCE CRESPO, David GUTIÉRREZ

Eur. J. Entomol. 108 (4): 651-658, 2011 | DOI: 10.14411/eje.2011.083

One of the best documented effects of climate change on biodiversity are shifts in phenology. However, long-term data quantifying and projecting the expected changes in phenology associated with climate warming are limited to a few well-recorded areas in the world. In the absence of temporal recording, an alternative approach is to determine the phenological response of species along marked gradients in climate or along latitudinal or altitudinal transects (space-for-time substitution). We studied the phenology (timing and duration of the flight period) of butterflies in 2006 along an altitudinal gradient (900-1680 m; estimated temperature lapse rate = -6.6°C/km) in the Serranía de Cuenca (central Spain) at the assemblage and individual species levels. Timing of the flight period was later for assemblages at high than at low altitudes. A similar trend of an increasing delay in the flight period with altitude was recorded for some individual species. However, there were also some exceptions to this pattern regardless of the number of sites and the altitudinal ranges of the species, suggesting possible local adaptation to regional climate. The duration of the flight period was shorter at high altitudes for assemblages, but this trend was not mirrored in the response of individual species. The results partly support substituting space-for-time when assessing the potential effect of climate change on phenophases such as the timing of the flight period, but we recommend extreme caution in extrapolating the results in the absence of information on how the responses of populations differ.

Discovery of Eutheiini (Coleoptera: Staphylinidae: Scydmaeninae) in Australia, with implications for phylogeny and biogeography of Paraneseuthia

Paweł JAŁOSZYŃSKI

Eur. J. Entomol. 108 (4): 687-696, 2011 | DOI: 10.14411/eje.2011.087

The scydmaenine tribe Eutheiini is recorded from Australia for the first time. Paraneseuthia carltoni sp. n. and P. booloumba sp. n. are described and illustrated, both from Queensland. In a parsimony-based phylogenetic analysis using adult morphological characters including genital features, the Australian species together with the Melanesian type species of Paraneseuthia Franz, P. peckorum Franz, were found to be more closely related to East Palearctic congeners than to most of the Paraneseuthia in the Sunda-Papuan area. The topology of the tree and biogeographic data suggest a Sundaland origin of this genus, with three major dispersal routes from a center located in present-day Sumatra: (i) north-eastern colonization of the Palearctic Far East, via a continental or island-arc route; (ii) south-eastern dispersal to East Australia; and (iii) eastern dispersal to Melanesia, possibly via the Quaternary Outer-Melanesian Arc. The important role of dispersal in the evolution of Paraneseuthia is supported by the presence of this genus on isolated volcanic islands, such as the southern Moluccas and Fiji, which were never connected to larger land masses.

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