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Results 631 to 660 of 1601:

Infestation of Narcissus poeticus by a scathophagid fly, Norellia melaleuca (Diptera: Scathophagidae)

Giuseppe CHICHIRICCÒ

Eur. J. Entomol. 107 (4): 677-680, 2010 | DOI: 10.14411/eje.2010.075

A little-known scathophagid fly is reported infesting the flowers and scapes of Narcissus poeticus growing in the Italian Central Apennines (AQ). This insect bores through the flower bud and lays an egg on the tepals. Both pistil and scape parenchymatous tissues provide the larva with nutrition, and the hollow stem a safe site for its metamorphosis. Infestation by this insect prevents the ovules from being fertilized as the larvae feed on the tisues in the style and so prevent the growth of pollen tubes.

Some observations on the reproductive biology of the scuttle fly Megaselia andrenae (Diptera: Phoridae) at the nesting site of its host Andrena agilissima (Hymenoptera: Andrenidae)

Carlo POLIDORI, R. Henry L. DISNEY, Francesco ANDRIETTI

Eur. J. Entomol. 101 (2): 337-340, 2004

Some behavioural aspects of the reproductive biology of Megaselia andrenae Disney, a kleptoparasite of the communal bee Andrena agilissima (Scopoli), were investigated at the nesting site of its host at Isola d'Elba (Italy). The scuttle fly mates more often in the early afternoon, which coincides with the period when the provisioning flights of its host are more frequent. The presence of the flies at the host nesting site, either in copula or single, is lower in the morning. In general only the females enter the host nests immediately after a mate, in a few cases closely followed by the males. When leaving the nest, females refuse to mate again with the males waiting outside. Observations on the ovaries of the females revealed no differences, either in the number of eggs or in the length of the most mature egg, between the individuals collected in copula or when flying alone. The species is sexually dimorphic, the females being larger than males. Male size does not seem to influence the females choice for mating.

Determining the season of death from the family composition of insects infesting carrion

Thiago De Carvalho MORETTI, Vinícius BONATO, Wesley Augusto Conde GODOY

Eur. J. Entomol. 108 (2): 211-218, 2011 | DOI: 10.14411/eje.2011.029

Determining the season of death by means of the composition of the families of insects infesting carrion is rarely attempted in forensic studies and has never been statistically modelled. For this reason, a baseline-category logit model is proposed for predicting the season of death as a function of whether the area where the carcass was exposed is sunlit or shaded and of the relative abundance of particular families of carrion insects (Calliphoridae, Fanniidae, Sarcophagidae, and Formicidae). The field study was conducted using rodent carcasses (20-252 g) in an urban forest in southeastern Brazil. Four carcasses (2 in a sunlit and 2 in a shaded area) were placed simultaneously at the study site, twice during each season from August 2003 through June 2004. The feasibility of the model, measured in terms of overall accuracy, is 64 ± 14%. It is likely the proposed model will assist forensic teams in predicting the season of death in tropical ecosystems, without the need of identifying the species of specimens or the remains of carrion insects.

Thermal requirements of Trissolcus grandis (Hymenoptera: Scelionidae), an egg parasitoid of sunn pest

Shahzad IRANIPOUR, Zahra Nozad BONAB, John P. MICHAUD

Eur. J. Entomol. 107 (1): 47-53, 2010 | DOI: 10.14411/eje.2010.005

Trissolcus grandis is an important egg parasitoid of sunn pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), the most serious pest of wheat in Iran. The thermal requirements of two populations of T. grandis were studied at five constant temperatures ranging from 20-32°C. Thermal thresholds for development were calculated using linear regression and degree-day models were determined by fitting non-linear equations to the data. The lower threshold for development was estimated to be 12.5 and 12.1°C, respectively, for males and females of the Bonab population, compared to 14.4 and 14.5°C for those of the Qaramalek population. Complete development required 143.8 and 162.8 degree-days, respectively, for males and females of the Bonab population and 116.9 and 124.6 for those of the Qaramalek population. Thus, wasps from the warmer region (Qaramalek) developed faster than those from the cooler region (Bonab), but had a higher thermal threshold for initiating development. Bonab females attained their highest fecundity (117.7 ± 7.2) at the lowest temperature tested (20°C), whereas the fecundity of Qaramalek females was maximal (96.8 ± 11.5) at 26°C. Biological control programmes that seek to augment wasp populations in wheat fields early in the spring, when natural rates of sunn pest parasitism tend to be low, should consider wasp thermal requirements to ensure the selection and release of locally-adapted parasitoids.

Meiotic karyotypes and testis structure of 14 species of the planthopper tribe Issini (Hemiptera: Fulgoroidea, Issidae)

Valentina G. KUZNETSOVA, Anna MARYAŃSKA-NADACHOWSKA, Vladimir M. GNEZDILOV

Eur. J. Entomol. 107 (4): 465-480, 2010 | DOI: 10.14411/eje.2010.055

Karyotypes and testis structure of 14 species representing 9 genera (Latissus, Bubastia, Falcidius, Kervillea, Mulsantereum, Mycterodus, Scorlupaster, Scorlupella and Zopherisca) of the planthopper tribe Issini (Issidae) are presented. All the karyotypes are illustrated by meiotic and occasionally mitotic figures. The male karyotypes of most of the species analyzed are 2n = 26 + X, the exception being Falcidius limbatus, which has a karyotype of 2n = 24 + neo-XY. The latter is the first report of the neo-XY system in the family Issidae. The species studied are found to be similar in having NORs on the largest pair of autosomes, but differ significantly in the amount and distribution of C-heterochromatin along the chromosomes. In contrast to the conserved chromosome numbers, the highly variable follicle number in the testes suggests rapid evolution of the tribe Issini. On the basis of its specific follicle number, it is proposed that Zopherisca tendinosa skaloula Gnezdilov & Drosopoulos, 2006 be upgrade to a species: Z. skaloula stat. n. The cytological and taxonomic significance of results presented are discussed.

Influence of linear versus network corridors on the movement and dispersal of the bush-cricket Metrioptera roeseli (Orthoptera: Tettigoniidae) in an experimental landscape

Anders ERIKSSON, Matthew LOW, Åsa BERGGREN

Eur. J. Entomol. 110 (1): 81-86, 2013 | DOI: 10.14411/eje.2013.010

Linear landscape elements are generally considered beneficial for promoting the movements of species between isolated habitats. However, relatively little consideration has been given to the effect of interconnections (nodes) between these elements: e.g. a simple linear element offers limited options for movement, whereas a network of such structures provides an exponential increase in potential pathways. In this pilot study we compared two experimental landscapes (single versus a lattice of four interconnected linear elements) in terms of their effect on the movement of males of Roesel's bush-cricket (Metrioptera roeseli) (Orthoptera: Tettigoniidae). Emigration of released bush-crickets from experimental landscapes was greater if there was a single rather than a lattice of linear elements (corridors). In the landscape with a lattice of corridors, 50% of the bush-crickets changed their direction of movement at nodes at least once. There was also evidence that nodes were attractive to bush-crickets; a higher proportion of individuals were found in and around nodes than in adjoining corridors, with the strength of this effect (i.e. aggregation at nodes) increasing with time. Thus nodes may not only affect the direction of movement but may also act as a local attractant. These effects may have an important role in the movement of species and their success in colonizing fragmented landscapes. These results indicate that in future landscape planning more consideration should be given to the connectivity between linear landscape elements as it is likely to be important in determining the movement and distribution of species.

Edge effects on ground-dwelling beetles (Carabidae and Staphylinidae) in oak forest-forest edge-grassland habitats in Hungary

Béla TÓTHMÉRÉSZ, Dávid D. NAGY, Szabolcs MIZSER, Dávid BOGYÓ, Tibor MAGURA

Eur. J. Entomol. 111 (5): 686-691, 2014 | DOI: 10.14411/eje.2014.091

Forest edges are essential to the maintenance of biodiversity at the landscape level. According to the edge effect hypothesis, diversity is higher in an edge than in adjacent areas. We tested the edge effect hypothesis for carabids and staphylinids in an oak forest-forest edge-grassland complex in the Hajdúság Landscape Protection Area (Hungary). The habitat types were as follows: (1) a closed oak forest with shrubs and herbaceous plants, (2) a forest edge with extensive ground vegetation and shrub cover and (3) grassland with dense herbaceous vegetation. We collected data from 60 pitfall traps (2 spatial replicates × 3 habitats × 10 traps). The GLM results showed that the species richness of carabids was higher at the edge of the forest than in the grassland and forest interior; the number of carabid individuals was highest in the grassland. The number of staphylinids and their species richness were significantly lower in the grassland than in the forest edge and interior. The results of principal coordinates analysis showed that the assemblages of both taxa in the forest edge and interior were separated from the assemblage in the grassland area. There were significant characteristic species for the edge habitat, as revealed by the IndVal (indicator species analysis) method. Our findings suggest that forest edges play a vital role in the maintenance of the diversity of carabid and staphylinid assemblages.

Effects on lepidopteran herbivores of feeding on leaves of transgenic birch (Betula pendula) expressing the sugar beet chitinase IV gene

Liisa VIHERVUORI, Päivi LYYTIKÄINEN-SAARENMAA, Jinrong LU, Hanna-Leena PASONEN

Eur. J. Entomol. 110 (2): 253-262, 2013 | DOI: 10.14411/eje.2013.038

Transgenic lines of silver birch (Betula pendula) carrying the sugar beet chitinase IV gene were used to study the effects of the heterologous expression of a transgenic chitinase on the performance of lepidopteran herbivores. The effect of wounding the leaves of birch on the performance of lepidopteran larvae and the growth of trees was also studied. Larvae of Orgyia antiqua L., Lymantriidae, and Phalera bucephala L., Notodontidae, were separately fed on the leaves of transgenic and wild-type birch, and their performance measured using nutritional indices. The relative growth rate (RGR) of O. antiqua larvae fed transgenic leaves was significantly lower than that of larvae fed wild-type leaves. Furthermore, there is little evidence that transgenic chitinase affects survival but it was lowest for the group of larvae fed leaves with the highest expression of chitinase IV. Wounding did not have a significant effect on the performance of the larvae or on the growth of the branches of the trees. The growth of branches of particular transgenic lines, however, was significantly associated with tree line. The performance of P. bucephala larvae fed leaves of transgenic and wild-type birches did not differ. The leaves used in both experiments from transgenic trees were shorter than those from wild-type trees. Using transgenic birch expressing sugar beet chitinase IV to improve the resistance of birch to fungal diseases can have negative effects on O. antiqua larvae feeding on the leaves of these birches. P. bucephala, however, was not similarly affected, which indicates that these two ecologically similar lepidopteran species may differ in their response to transgenic chitinase.

Biology of Rhembobius quadrispinus (Hymenoptera: Ichneumonidae): Pupal parasitoid of saprophagous species of syrphids (Diptera: Syrphidae)

Pilar HURTADO, Celeste PÉREZ-BAÑÓN, Santos ROJO

Eur. J. Entomol. 111 (3): 379-385, 2014 | DOI: 10.14411/eje.2014.040

Little is known about the life cycle of Rhembobius parasitoids (Hymenoptera: Ichneumonidae). Known host records are mainly from saprophagous species of hoverflies of the tribe Eristalini (Diptera: Syrphidae), whose larvae develop in a wide range of aquatic and semi-aquatic breeding sites that are rich in microbial decay. We present an account of the biology and important details of the life cycle of the pupal parasitoid R. quadrispinus in both natural and controlled conditions. Host suitability, the influence of host pupal age and age of the female parasitoid on her production of progeny was evaluated in laboratory tests. Our results showed that the percentage of pupae of E. tenax that were parasitized by R. quadrispinus decreased as pupae matured, and the optimal age for successful parasitism ranged from 1 to 3 days. This biological information could be useful in the biological control of anthropophilic saprophagous eristalines that can act as potential mechanical vectors of pathogens on farms.

The ladybird beetle Harmonia axyridis (Coleoptera: Coccinellidae) as a possible predator of grape phylloxera Daktulosphaira vitifoliae (Hemiptera: Phylloxeridae)

Susanne KÖGEL, Manuela SCHIELER, Christoph HOFFMANN

Eur. J. Entomol. 110 (1): 123-128, 2013 | DOI: 10.14411/eje.2013.017

The ladybird beetle Harmonia axyridis (Pallas 1773) has been used for biological control in several countries. However, it became invasive in some of those countries. Coccinella septempunctata (Linné 1758) is a native species in Europe. It feeds mainly on aphids and can be very abundant. As far as is known there are no effective natural enemies of the grape phylloxera Daktulosphaira vitifoliae (Fitch 1855) in Europe. The potential of the above two ladybird species for reducing the abundance of the grapevine pest D. vitifoliae has not been previously investigated. In this study, the consumption and developmental parameters of H. axyridis and C. septempunctata fed on D. vitifoliae were determined in the laboratory. In a field trial, the occurrence of H. axyridis on grapevines with or without leaf galls of D. vitifoliae was compared. In contrast to C. septempunctata, H. axyridis was able to complete its development using D. vitifoliae as a source of food. In addition, adult H. axyridis consumed significantly more D. vitifoliae eggs than C. septempunctata. Within 24 h H. axyridis consumed up to 1400 eggs of D. vitifoliae. However, based on the fitness parameters "developmental time", percentage "survival" and "adult weight", this diet was less suitable for H. axyridis than the eggs of Ephestia kuehniella. During field observations over a period of two years H. axyridis was repeatedly observed feeding on grape phylloxera leaf galls, which indicates that H. axyridis uses grape phylloxera as prey. H. axyridis was significantly more abundant on leaves with leaf galls of D. vitifoliae than on leaves without galls. C. septempunctata was rarely found on grape leaves with or without leaf galls. These results indicate that overall H. axyridis, unlike C. septempunctata, is a predator of D. vitifoliae and could potentially reduce grape phylloxera numbers in vineyards.

The efficiency of pitfall traps as a method of sampling epigeal arthropods in litter rich forest habitats

Johanna SIEWERS, Jens SCHIRMEL, Sascha BUCHHOLZ

Eur. J. Entomol. 111 (1): 69-74, 2014 | DOI: 10.14411/eje.2014.008

Pitfall trapping is an approved self-sampling method for capturing epigeal arthropods for ecological and faunistic studies. Capture efficiency of pitfall traps may be affected by external factors and the design of the trap. Pitfall traps set in forests are usually protected with covers or wire grids, but the effect of these constructions on sampling efficiency as well as their practicability and necessity have so far received little attention. During the present study pitfall traps of four different designs (covers, wire grids, litter exclosure, open) were tested in terms of their efficiency in capturing ground-dwelling arthropods (Acari, Araneae, Carabidae, Formicidae, Isopoda, Myriapoda, Opiliones) in order to gain a better understanding of the applicability and reliability of pitfall traps in forests. The study was carried out in an oak-beech forest in Northwest Germany using a total of 40 pitfall traps (ten replicates per trap design). Generalised linear models indicated no significant differences in arthropods counts among catches of pitfall traps of the four different designs, except for woodlice. Ordination analyses (NMDS) and MANOVA revealed no significant differences in spider and carabid beetle species compositions of the catches. In contrast, for both these taxa there were significant differences in the body sizes of the individuals caught. We conclude that the catches of pitfall traps are little affected by their design. Furthermore, the litter layer and litter input have no effect on the capture efficiency and thus there seems to be no need to protect pitfall traps with covers or wire grids in litter rich forest habitats.

Effect of temperature on population growth and life table parameters of Nephus arcuatus (Coleoptera: Coccinellidae)

Sara ZARGHAMI, Farhan KOCHEILI, Mohammad S. MOSSADEGH, Hossein ALLAHYARI, Arash RASEKH

Eur. J. Entomol. 111 (2): 199-206, 2014 | DOI: 10.14411/eje.2014.017

The development, reproduction and life table parameters of the predator Nephus arcuatus Kapur (Coleoptera: Coccinellidae), the most important predator of the spherical mealybug, Nipaecoccus viridis (Newstead) (Homoptera: Pseudococcidae) were studied at five constant temperatures (15, 20, 25, 30 and 35 ± 1°C, 65 ± 5% RH and a photoperiod of 14L : 10D). The duration of total pre-adult stage was found to decrease with increase in temperature from 60.0 days at 20°C to 15.3 days at 35°C. The oviposition period lasted 58.5, 44.7, 53.2 and 24.5 days at 20, 25, 30 and 35°C, respectively, with females laying an average of 164.8, 415.2, 660.4 and 136.6 eggs, respectively, at these four temperatures. Life table data were analyzed using an age-stage, two-sex life table. The intrinsic rate of increase (rm = 0.1540 d-1), finite rate of increase (λ = 1.1666 d-1) and net reproductive rate (R0 = 197.9 offspring) were greatest at 30°C. The shortest mean generation time (T= 30.6 days) was recorded at 35°C. These results indicate that N. arcuatus can successfully survive and reproduce at temperatures of around 30°C and has the potential to be an effective biological control agent of N. viridis and other mealybugs in warm regions.

Chromosomal mapping of two Mariner-like elements in the grasshopper Abracris flavolineata (Orthoptera: Acrididae) reveals enrichment in euchromatin

Octavio M. PALACIOS-GIMENEZ, Danilo BUENO, Diogo C. CABRAL-DE-MELLO

Eur. J. Entomol. 111 (3): 329-334, 2014 | DOI: 10.14411/eje.2014.052

The occurrence of transposable elements (TEs) is a ubiquitous characteristic of eukaryotic genomes, and these sequences are highly abundant in some species. Due to their large genomes, grasshoppers (Orthoptera) appear to be potentially good candidates in terms of having genomes that harbour considerable numbers of TEs. In the present study, we have investigated the occurrence of two Mariner-like elements (MLEs) within the genome of the grasshopper, Abracris flavolineata (De Geer, 1773), describing their distribution in both the A (i.e. standard or normal) complement and B chromosomes. PCR amplification followed by cloning and sequencing revealed two Mariner-like elements, which were named Afmar1 and Afmar2. Moreover, subsequent fluorescence in situ hybridization (FISH) assays indicated an abundance of these elements in the euchromatic regions of all the standard complement chromosomes and an absence of such sequences in heterochromatic regions. These sequences were also abundant in the euchromatic B chromosome: Afmar1 was distributed along the entire length of the chromosome, whereas Afmar2 was restricted to the proximal/interstitial regions of the chromosomal long arm. The general aspects of the distribution patterns of the two MLEs are discussed as well as their possible involvement in the origin and diversification of the B chromosome in A. flavolineata.

Rarity of blister beetles (Coleoptera: Meloidae) in Southern Africa correlates with their phylogeny and trophic habits, but not body size

Monica PITZALIS, Valentina AMORE, Francesca MONTALTO, Luca LUISELLI, Marco A. BOLOGNA

Eur. J. Entomol. 111 (4): 529-535, 2014 | DOI: 10.14411/eje.2014.058

Ecologists have identified several correlates of biological rarity in animals. Among the various correlates identified so far, three are explored in this paper: (a) abundance is correlated with absolute body size in animals; (b) phylogenetically primitive taxa are overrepresented in samples of rare species; (c) more specialized species are rarer than less specialized species. Here we use Namibian blister beetles (Coleoptera: Meloidae) as a model system for exploring these issues. We used data from five field expeditions, which resulted in the identification of 891 beetles belonging to 76 species collected from 191 sites. 13% of the species accounted for over 50% of the individuals; 22% of all species were represented by singletons. Abundance patterns differed significantly among the different trophic categories, with non-pollinophagous (non-specialized) species being more abundant than weed-eaters and pollinophagous (specialized) species. Species of phylogenetically basal tribes were less abundant than those of more derived groups. Trophic category and phylogenesis did not have a synergic effect in determining the relative abundance of the species, and body size had no influence on their abundance.

The effects of overwintering, sex, year, field identity and vegetation at the boundary of fields on the body condition of Anchomenus dorsalis (Coleoptera: Carabidae)

Eliąka BARANOVSKÁ, Michal KNAPP, Pavel SASKA

Eur. J. Entomol. 111 (5): 608-614, 2014 | DOI: 10.14411/eje.2014.085

Body condition, in terms of body mass corrected for structural body size, represents an animal s energetic reserves and is an indicator of the health and fitness of an organism. This study investigates the variability in the body condition of the carabid beetle, Anchomenus dorsalis, in time and space at a small scale. The beetles were collected in four fields with two types of boundary (grassy and forest) near Prague-Suchdol in autumn 2009 and 2010 and in spring 2010 and 2011. Body condition was significantly affected by overwintering (the body condition of post-overwintering individuals collected in spring was worse than that of pre-overwintering individuals collected in autumn), sex (females were in better condition than males) and to a lesser extent by sampling year, field identity and several interactions, e.g., overwintering : sex (greater decrease in body condition during overwintering in males than in females), overwintering : year (difference in body condition between pre-overwintering and post-overwintering individuals was greater in 2009/2010 than 2010/2011). Type of boundary had no substantial effect on the body condition of A. dorsalis. This study shows the importance of sampling body condition several times a year for more than one season, which has rarely been performed to date.

Forest moth assemblages as indicators of biodiversity and environmental quality in a temperate deciduous forest

Jeong-Seop AN, Sei-Woong CHOI

Eur. J. Entomol. 110 (3): 509-517, 2013 | DOI: 10.14411/eje.2013.067

The aim of the present study was to find groups of moths suitable for estimating changes in the abundance and richness of local and regional biodiversity in a temperate forest. We captured macro-moths from May to October over a 5-year period (2005-2009) at various sites in Mt. Jirisan National Park (JNP) in southern Korea. Six taxa were selected based on a strong correlation between the number of species in these taxa and total number of species of large moths: Ennominae (Enn), Arctiinae (Arc), Hermininae (Her), Notodontidae (Not), Drepanidae (Dre) and Ophiderinae (Oph). Of these, combinations of four groups were found to have the best predictive capability. We determined whether these indicator groups could be used to reveal mean differences in species abundance according to spatial (forest type, altitude) and temporal variables (monsoon season) since moth composition and abundances were closely related with these variables. The mean differences in the groups of moths in the two types of forest (Arc, Dre, Enn, Not), two altitudes (Dre, Enn, Her, Oph) and two seasons (Dre, Enn, Oph) were significant. Overall, it was revealed that a set of four groups, including two taxa (Dre and Enn), could be used to show differences in local and regional biodiversity of moths in southern Korean temperate forest.

Cold storage affects mortality, body mass, lifespan, reproduction and flight capacity of Praon volucre (Hymenoptera: Braconidae)

Juracy Caldeira LINS Jr., Vanda Helena Paes BUENO, Livia Alvarenga SIDNEY, Diego Bastos SILVA, Marcus Vinicius SAMPAIO, Janser Moura PEREIRA, Quintiliano Siqueira Schroden NOMELINI, Joop C. van LENTEREN

Eur. J. Entomol. 110 (2): 263-270, 2013 | DOI: 10.14411/eje.2013.039

The possibility of storing natural enemies at low temperatures is important for the mass production of biological control agents. We evaluated the effect of different periods of cold storage on immature mortality, mummy body mass, lifespan, reproduction and flight capacity of the parasitoid Praon volucre (Haliday). One-day-old mummies of the aphid Macrosiphum euphorbiae (Thomas) containing pre-pupae of P. volucre were stored in a climatic chamber at 5°C and 70 ± 10% RH in the dark for different periods of time (5, 10, 15 and 20 days). The control consisted of mummies kept at 22 ± 1°C, 70 ± 10% RH and a 12 h photophase. Percentage adult emergence, mummy body mass, flight capacity and number of eggs in the ovarioles of P. volucre females decreased with increase in the period of storage, while the longevity of females was only slightly affected. Fat content of mummies, percentage of parasitized aphids and survival of progeny to emergence decreased with increase in the period of storage. Storage of P. volucre pre-pupae for up to 5 days at 5°C did not affect any of the above mentioned parameters. The fact that P. volucre pre-pupae can be stored for 5 days without loss of quality and for 10 days with only a slight loss facilitates the planning of mass production and shipment.

Gas exchange patterns in Platynus assimilis (Coleoptera: Carabidae): Respiratory failure induced by a pyrethroid

Irja KIVIMÄGI, Aare KUUSIK, Angela PLOOMI, Luule METSPALU, Katrin JÕGAR, Ingrid H. WILLIAMS, Ivar SIBUL, Külli HIIESAAR, Anne LUIK, Marika MÄND

Eur. J. Entomol. 110 (1): 47-54, 2013 | DOI: 10.14411/eje.2013.006

Discontinuous gas exchange (DGE) is the main (23 individuals) breathing mode in resting adult Platynus assimilis. Few of the beetles tested (13 individuals) displayed a pattern of cyclic gas exchange or CGE. The burst of CO2 release in DGE and CGE was always accompanied by abdominal pumping (active ventilation or V). Seven individuals displayed a pattern of continuous respiration, characterized by regular abdominal pumping. Resting metabolic rate (RMR) in continuously breathing beetles was higher than in those using DGE and CGE. After treatment with sub-lethal doses of alpha-cypermethrin DGE ceased. Treated beetles were characterized by continuous pumping and almost regular periods of activity. RMR increased significantly after treatment with a pyrethroid.

Life in two dimensions or keeping your head down: Lateral exuvial splits in leaf-mining larvae of Pachyschelus (Coleoptera: Buprestidae) and Cameraria (Lepidoptera: Gracillariidae)

Vasily V. GREBENNIKOV

Eur. J. Entomol. 110 (1): 165-172, 2013 | DOI: 10.14411/eje.2013.024

This paper describes previously unreported lateral cuticle splits occurring during the moulting of larvae of the leaf-miners Pachyschelus laevigatus (Say, 1839) (Coleoptera: Buprestidae) and Cameraria sp. (Lepidoptera: Gracillariidae). In these species the cuticle does not split dorsally during the larval/larval moults as in most insects, but laterally, thus permitting the larva to leave its exuviae sideways rather than vertically. This previously overlooked phenomenon is hypothesized to have evolved independently in both taxa and is an adaptation to life in the vertically limited space of their mines and, therefore, might be found in other organisms confined to similar conditions. The exuvial split in the larva to pupa moult of Cameraria sp. taking place inside a relatively tick and firm cocoon is, however, of the regular dorso-medial type, and, therefore, two different successive types of moult occur within a single ontogenesis. For comparative purposes the common dorsal exuvial split is described and illustrated for the leaf-mining larvae of Profenusa alumna (Hymenoptera: Tenthredinidae), Sumitrosis rosea (Coleoptera: Chrysomelidae) and the free-living Satonius fui (Coleoptera: Torridincolidae).

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.

A goodbye letter to alcohol: An alternative method for field preservation of arthropod specimens and DNA suitable for mass collecting methods

Pavel POKLUDA, Lukáą ČÍ®EK, Eva STŘÍBRNÁ, Lukáą DRAG, Julius LUKE©, Vojtěch NOVOTNÝ

Eur. J. Entomol. 111 (2): 175-179, 2014 | DOI: 10.14411/eje.2014.024

Despite its limitations, ethanol remains the most commonly used liquid for the preservation of arthropod specimens and their DNA in the field. Arthropod ecology and taxonomy have witnessed a substantial increase in the use of various trapping and molecular methods in the past two decades. However, the methods of collecting and the preservation liquids most widely used in arthropod traps do not properly preserve DNA. Trap-collected specimens are typically of limited utility for molecular studies due to the poor preservation of DNA. A stable and cheap substance that can be used to trap arthropods in and preserve their DNA is therefore needed. Here we test whether (i) 2% SDS, 100mM EDTA, (ii) 1% SDS, 50mM EDTA and (iii) 0.66% SDS, 33mM EDTA can preserve DNA of small and medium-sized beetles for one, four and eight weeks. Preservation of DNA was tested using PCR amplification of parts of the mitochondrial cytochrome c oxidase I (Cox1) and nuclear 28S rRNA genes. All the solutions tested preserved DNA for at least up to eight weeks and we recommend 2% SDS and 100mM EDTA as a cheap, stable and easily transportable alternative to ethanol for preserving specimens and their DNA collected in the field. This solution is also suitable for using as the collection and preservation liquid in arthropod traps.

Numerical response of Nesidiocoris tenuis (Hemiptera: Miridae) preying on Tuta absoluta (Lepidoptera: Gelechiidae) in tomato crops

Juan A. SANCHEZ, Michelangelo LA-SPINA, Alfredo LACASA

Eur. J. Entomol. 111 (3): 387-395, 2014 | DOI: 10.14411/eje.2014.041

Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is an effective predator of pests of tomato crops and a promising biocontrol agent of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in the Mediterranean area. The aim of this study was to determine the numerical response of N. tenuis to different levels of abundance of T. absoluta and its potential for controlling it when infesting tomato crops. The effects of infesting plants with either 0.2 or 2 larvae of T. absoluta and releasing either 2 or 0 adults of N. tenuis per plant were assayed in a complete factorial randomised-block design with 3 repeats in 12 greenhouse compartments in southern Spain. The population dynamics of the moth was similar in all compartments, with and without N. tenuis, but T. absoluta reached a lower absolute peak density in compartments with N. tenuis (29.1 ± 8.2 larvae per leaf) than in those without them (44.5 ± 19.4 larvae per leaf). The peak numbers of larvae of T. absoluta did not differ on the plants initially infested with 0.2 or 2 larvae. Nesidiocoris tenuis reached a maximum of 1.9 ± 0.43 and 3.0 ± 0.4 individuals per leaf in compartments in which low and high numbers of T. absoluta were initially introduced, respectively. The yield of tomatoes was higher in the treatments with N. tenuis than in those without, but the percentage of damaged fruit (> 50%) was similar. The slow numerical response of N. tenuis might have been due, among other things, to the poor establishment of this mirid due to the scarcity of prey. N. tenuis densities of about 0.2 individuals per leaf during the linear population growth phase of T. absoluta (0.5 to 3 larvae per leaf) did not prevent outbreaks.

More evidence for an admixture of the Hyles euphorbiae complex's main lineages in Mediterranean Europe (Lepidoptera: Sphingidae)

Michael B. MENDE, Anna K. HUNDSDOERFER

Eur. J. Entomol. 111 (4): 584-587, 2014 | DOI: 10.14411/eje.2014.065

The populations of the Hyles euphorbiae complex on Crete and the Dodecanese Islands have been described as an endemic species, Hyles "cretica". Alternatively, they are thought to be of hybrid origin from the complex's two main lineages, the European H. euphorbiae and African H. tithymali, because of their intermediate morphology. That they belong to a discrete taxon is supported by the fact that all the recent samples analyzed belong to an endemic mitochondrial haplotype cluster; however, this cluster is so close to the tithymali cluster that it might also be regarded as a sublineage of H. tithymali. Similarly, southern Italy is currently dominated by another distinct tithymali-related cluster, named "italica". However, sequencing of historic museum specimens, which were collected in Italy during the past century, revealed that mitochondrial haplotypes of H. euphorbiae were once present throughout the entire range of "italica" thus contradicting a long-term isolated evolution of a southern Italian refugial entity. In the present study we likewise sequenced the few available historic specimens from the Aegean Islands and also found a specimen from Crete which belonged to the euphorbiae cluster. In conclusion, southern Italian and southern Aegean populations both appear to be dynamic hybrid mixtures of the European H. euphorbiae and African H. tithymali, rather than separately evolved taxa.

The effect of the construction and renovation of a highway bypass in Central Poland on the carabid beetle fauna (Coleoptera: Carabidae)

Izabela DYMITRYSZYN

Eur. J. Entomol. 111 (5): 655-662, 2014 | DOI: 10.14411/eje.2014.081

The aim of this research was to define the effect of the construction and renovation of a highway bypass around the town of Skępe on the environment and assemblages of carabid beetles. This four-year study was based on catching samples of beetles using pitfall traps. The traps were set first in 2008 and later from 2010 to 2012, after the renovation of the road, along roadside verges adjacent to two ca. 100-year-old pine forest stands, wet habitats and fallows of arable fields and inside these habitats about 25 m from the road (control plots). The carabids collected were identified to species and numbers of individuals and dominance values of each of the species were calculated for each study plot and each year. Furthermore, the dominance of the different species of plants was assessed. Numbers of species, numbers of individuals, percentage share of forest species and individuals, and Shannon diversity values of the carabid assemblages were analyzed. Multivariate statistical analyses (ordinations) were carried out using the dominance of the different species of carabids and using the ecological indicator values of plants as environmental factors. The construction of the bypass in 1987 resulted in more diversified carabid assemblages along the roadsides. Carabid fauna along the roadsides differed from that in the control plots in forests and in terms of some parameters from the control plots in wet habitats, but not statistical from the control plots in the fallow areas of arable fields. The renovation of the road 22 years after construction did not result in any significant changes in the characteristic parameters of the carabid assemblages along the roadsides, but gradient analysis indicated that it did have an effect. In terms of the environmental conditions of the habitats based on the plant associations occurring there the roadside habitats differed from the control plots in forests and wetlands. Since the number of sites studied is rather low, the results of this study have to be considered to be preliminary, but may provide research hypotheses for further research on highway roadsides.

Endosymbiont-free ants: Molecular biological evidence that neither Wolbachia, Cardinium or any other bacterial endosymbionts play a role in thelytokous parthenogenesis in the harvester ant species, Messor barbarus and M. capitatus (Hymenoptera: Formicidae)

Paloma MARTÍNEZ-RODRÍGUEZ, Jonás SARASA, Begoña PECO, Berta M. JAUREGUI, Desiree RIVERA, Jose L. BELLA

Eur. J. Entomol. 110 (2): 197-204, 2013 | DOI: 10.14411/eje.2013.030

Thelytokous parthenogenesis is a type of sex determination in which females are produced from unfertilized eggs. Genetic and endosymbiont-induced forms of thelytoky have been described in the Hymenoptera. Our study has revealed that Wolbachia, Cardinium, Spiroplasma and other endosymbionts are probably absent in Iberian populations of harvester ants, Messor barbarus and Messor capitatus (Hymenoptera: Formicidae: Myrmicinae) and are thus not involved as factors in the sex determination of these two species. Our results lend weight to previous suggestions that bacterial parthenogenesis induction in Hymenoptera is probably limited to the reproductive systems of chalcidoid and cynipoid parasitoid wasps (Hymenoptera: Apocrita: Chalcidoidea and Cynipoidea, respectively).

Cytogenetic variability among Bradyporinae species (Orthoptera: Tettigoniidae)

Elżbieta WARCHAŁOWSKA-¦LIWA, Beata GRZYWACZ, Anna MARYAŃSKA-NADACHOWSKA, Tatyana V. KARAMYSHEVA, Dragan P. CHOBANOV, Klaus-Gerhard HELLER

Eur. J. Entomol. 110 (1): 1-12, 2013 | DOI: 10.14411/eje.2013.001

Chromosomes of six European species (one with two subspecies) of Orthoptera belonging to the tribes Ephippigerini and Bradyporini were analyzed using C-banding, Ag-NOR, DAPI (AT-rich)/CMA3 (GC-rich) staining and fluorescence in situ hybridization (FISH) using the 18S rDNA and (TTAGG)n telomeric probes with the aim to better understand chromosomal organization and evolutionary relationships between genera and subgenera within and across both tribes. The evolution of karyotypes was studied in terms of changes in chromosome number (2n) and morphology (FN, the fundamental number - i.e. the number of chromosome arms including the X chromosome). The ancestral 2n = 31 was reduced to 2n = 29 (FN = 31) and 27 (FN = 31) by one or two Robertsonian fusions in the Ephippigerini. Whereas in the Bradyporini 2n = 27 (FN = 32) as a result of two Robertsonian translocations and a pericentric inversion in the X chromosome. The quantity of heterochromatin in GC-rich regions distinguished the karyotypes of Ephippigerini (only a single CG-rich band on one autosome pair) from those of Bradyporini (CG-rich bands on all chromosomes). FISH using the 18S rDNA probe localized 1-3 rDNA clusters to autosomes and/or to the X chromosome in all species examined. The rDNA loci coincided with active NORs as determined by Ag-NOR staining. A comparison of the location of the single NOR/rDNA in two species of the genus Steropleurus (Ephippigerini) suggests that the reduced chromosome number in S. pseudolus results from a Robertsonian fusion between two pairs of autosomes, one of them carrying the NOR/rDNA as in S. stalii (and also in E. ephippiger). Whereas the karyotypes of three species of the genus Bradyporus, though showing the same chromosome number and morphology, differed in the number and distribution of NORs/rDNA sites [one autosomal in B. (B.) dasypus versus three in B. macrogaster and B. (C.) oniscus, two of them X-linked]. Trends in karyotype diversification of the taxa based on the present data and previous research are discussed. In some individuals belonging to the species Bradyporus (B.) dasypus and B. (C.) m. macrogaster B chromosomes (Bs) were detected: acrocentric (the smallest elements in the complement) and submetacentric (similar to medium-sized autosomes), respectively.

Habitat use governs distribution patterns of saprophagous (litter-transforming) macroarthropods - a case study of British woodlice (Isopoda: Oniscidea)

Bethan V. PURSE, Steve J. GREGORY, Paul HARDING, Helen E. ROY

Eur. J. Entomol. 109 (4): 543-552, 2012 | DOI: 10.14411/eje.2012.068

Despite the importance of saprophagous macroarthropods as key facilitators of plant litter decomposition within ecosystems and their likely sensitivity to global climate change and land-use change, a lack of ecological data has precluded attempts to explain their distribution patterns in terms of traits. Using an extensive set of large-scale and long-term biological records, the distribution patterns of 33 woodlice (Crustacea: Oniscidea) species in Britain were characterised by their range size (area of occupancy) and aggregation (degree to which occupied squares are clustered across the range). Body size and seven ecological traits were examined as correlates of range size and fill, while controlling for phylogeny and recording intensity, and comparing fine and broad-scale measures of habitat heterogeneity. Species that used a greater diversity of habitats had larger range sizes. Broad categorisation of habitats (by dominant vegetation) alongside other traits was less accurate in predicting range size than fine-scale habitat (microsites where individuals were discovered) data. The latter explained 25% more variance than broad-scale habitat data, highlighting the value of coupling biological recording of species with data on micro-habitat. Habitat use is an important trait in explaining distribution patterns and we conclude that ensuring land cover heterogeneity will favour conservation of saprophagous macro-arthropod diversity.

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%.

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.

Comparison of the mating behaviour of a bush cricket in the laboratory and the field: Calling activity and mating frequency of a long-winged species, Phaneroptera falcata (Ensifera: Tettigoniidae)

Jörg SAMIETZ, Jens SCHUMACHER, Klaus REINHARDT

Eur. J. Entomol. 111 (2): 189-197, 2014 | DOI: 10.14411/eje.2014.019

Bush crickets are a model group for testing hypotheses in sexual selection, but much of the information is based on laboratory observations on wingless or short-winged species, which may restrict their generality. Here we describe aspects of the mating behaviour of the long-winged European bush cricket Phaneroptera falcata (Poda, 1761). Both in the laboratory and the field, diel calling followed a normal, though slightly left-skewed distribution, peaking about three hours after sunset or lights-off. Under bright greenhouse conditions, when the light was suddenly switched off, calling occurred only after the onset of darkness. Decreasing light intensity may trigger the start of calling activity. In the field, calling decreased from midnight onwards, which may be related to a decrease in temperature. The sequence of events during copulation was identical in the laboratory and the field. However, in two of 14 copulations documented in the field, a pre-copulatory behaviour was observed that resembled the putative removal and ingestion of rival sperm. Previous suggestions that P. falcata (Poda) is monogamous are rejected on the basis of both laboratory and field results. In the laboratory males and females mated every 2.3 and 3.6 days, respectively. We introduce a simple way to calculate the average frequency of mating in the field, based on the observation that at any one time 3% of all the individuals are recorded mating and copulation lasts 15 min. We estimate that on average P. falcata (Poda) mates once per day. More generally, our results show it is important for evolutionary conclusions to measure behaviourial data in the field.

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