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Results 361 to 390 of 825:

Biochemistry and biosynthesis of insect pigments

Gulsaz SHAMIM, Sanjeev K. RANJAN, Dev M. PANDEY, Ranganathan RAMANI

Eur. J. Entomol. 111 (2): 149-164, 2014 | DOI: 10.14411/eje.2014.021

The functional role and commercial importance of insect pigments have been studied for well over a century. They are classified into those synthesized by insects, which include anthraquinones, aphins, pterins, tetrapyrroles, ommochromes, melanins and papiliochromes, and those sequestered from their host plants, the antioxidative carotenoids and water-soluble flavonoids. They can also be categorized into those that are produced by cyclization of linear precursors, e.g. anthraquinones, aphins and tetrapyrroles and those derived from cyclic precursors such as pterins, ommochromes, melanins and anthocyanins. Anthraquinones and aphins are derived by cyclization of linear polyketides via successive condensation of simple carboxylic acid metabolites and occur in two major Superfamilies of Hemiptera, the Coccoidea and Aphidoidae, respectively. Ommochromes, tetrapyrroles and melanins are derived from different amino acid precursors, tryptophan, glycine and tyrosine, respectively. Apart from providing body colouration, ommochromes are visual pigments, melanins act as a protectant against UV and tetrapyrroles facilitate oxygen transport to cells. Papiliochromes are synthesized using both, the essential amino acids tyrosine and tryptophan. Pterins are derived from guanosine triphosphate (GTP) and are also present in ommatidia of eyes. The sequestered pigments, anthocyanins and carotenoids, are synthesized from phenylalanine and by condensation of two isoprene units, respectively, in plants. The biosyntheses of chemochromes in insects are governed by a complex set of enzymes, pathways and genetics. This review provides a comprehensive understanding of the molecules that are not only responsible for the striking colours but also provide functional benefits for insects. The commercially important pigments are also discussed.

Aphid honeydew: An arrestant and a contact kairomone for Episyrphus balteatus (Diptera: Syrphidae) larvae and adults

Pascal D. LEROY, Raki ALMOHAMAD, Sabrine ATTIA, Quentin CAPELLA, François J. VERHEGGEN, Eric HAUBRUGE, Frédéric FRANCIS

Eur. J. Entomol. 111 (2): 237-242, 2014 | DOI: 10.14411/eje.2014.028

Predator searching efficiency increases in response to a variety of environmental cues associated with its prey. The sugary excretion of aphids (honeydew) has been found to act as a prey-associated cue for many aphid natural enemies. In the present study, the honeydew excreted by Acyrthosiphon pisum (Harris) was identified as an arrestant and a contact kairomone for young larvae and adults of a common predatory hoverfly, Episyrphus balteatus (De Geer) (Diptera: Syrphidae). First and second instar larvae increased their foraging behaviour in the honeydew-treated area. When plants were sprayed with crude honeydew, the speed of movement of female E. balteatus was significantly higher than in controls, resulting in a longer period of time spent on treated plants and laying eggs. We conclude that the honeydew excreted by A. pisum induces searching behaviour and acts as and arrestant not only for adults but also for young E. balteatus larvae.

Prevalence of male-killer in a sympatric population of two sibling ladybird species, Harmonia yedoensis and Harmonia axyridis (Coleoptera: Coccinellidae)

Suzuki NORIYUKI, Yuichi KAMEDA, Naoya OSAWA

Eur. J. Entomol. 111 (2): 307-311, 2014 | DOI: 10.14411/eje.2014.029

In predatory ladybirds male embryos in clutches of eggs infected with male-killing bacterial endosymbionts do not hatch and are consumed by female hatchlings. Moreover, it is predicted that infection with male-killing bacteria should be prevalent in a ladybird population if the fitness advantage to female ladybirds due to the resulting reallocation of resources is high. We compared male-killer bacterial prevalence in two sibling species of the ladybird genus Harmonia that use different host ranges. Harmonia yedoensis feeds mostly on the highly elusive pine aphid and its hatchlings can greatly enhance their ability to capture prey and thus their survival by consuming un-hatched eggs in the clutch. In contrast, Harmonia axyridis feeds on a wide range of prey and consumption of un-hatched eggs by the hatchlings does not necessarily increase their foraging success. In the study area where these two species of ladybird occur sympatrically 14 of the 22 females of H. yedoensis (64%) laid clutches of eggs of which approximately only a half hatched and did not produce male offspring, whereas only one of 12 of the females of H. axyridis (8%) exhibited symptoms indicating infection with male-killing bacteria. In the H. yedoensis that exhibited symptoms of being infected with male-killing bacteria, the total allocation of resources to each hatchling, which was provided by laying larger eggs and eating the un-hatched eggs in the clutch, was considerable. These results suggest that the difference in the prevalence of infection with male-killing bacteria in these two species of ladybird may reflect differences in the quality of their prey and their foraging behaviour.

Does the prediction of the time of egg hatch of Thaumetopoea processionea (Lepidoptera: Notodontidae) using a frost day/temperature sum model provide evidence of an increasing temporal mismatch between the time of egg hatch and that of budburst of Quercus robur due to recent global warming?

Eiko WAGENHOFF, Annika WAGENHOFF, Rainer BLUM, Holger VEIT, Daniel ZAPF, Horst DELB

Eur. J. Entomol. 111 (2): 207-215, 2014 | DOI: 10.14411/eje.2014.030

Thaumetopoea processionea is a serious defoliator of oak and of medical concern whose abundance has consistently increased throughout Europe during the past two decades. This study validates a previously published frost day/temperature sum model for predicting time of egg hatch of this species using five years of recent field data from South-West Germany. This model proved satisfactory for predicting the time of egg hatch of T. processionea. Hence, the model was used to retrospectively predict the time of egg hatch of T. processionea in the Karlsruhe area, which indicates that the time of egg hatch has fluctuated over the past 130 years. In the last two decades, however, predicted time of egg hatch is much earlier than the long-term average due to the increase in winter and early spring temperatures. Comparison of predicted time of egg hatch of T. processionea and long-term records of the time of foliation of its common host Quercus robur revealed that in the study area the temporal advance in the timing of both events was similar. This is not in accordance with recently published research on spring-feeding folivores, which report a diverging trend in the timing of egg hatch and budburst of their host plants as a consequence of human-induced climate change.

Comparative suitability of aphids, thrips and mites as prey for the flower bug Orius sauteri (Hemiptera: Anthocoridae)

Su WANG, J.P. MICHAUD, Fan ZHANG

Eur. J. Entomol. 111 (2): 221-226, 2014 | DOI: 10.14411/eje.2014.031

The predatory bug Orius sauteri (Poppius) (Hemiptera: Anthocoridae) is an important biological control agent in Asia that is often released on field crops and in greenhouses to control pests on vegetable and ornamental plants. This study compared the developmental and reproductive performance of O. sauteri on monotypic diets of four aphid species, western flower thrips, and two-spotted spider mite. Thrips emerged as the optimal prey type, consistent with findings for many other Orius spp. A diet of Frankliniella occidentalis (Pergande) yielded the fastest development, largest adult body size, shortest pre-oviposition period, and highest fecundity and longevity. Tetranychus urticae (Koch) was the next most suitable prey by most performance measures. Among aphids, Myzus persicae (Sulzer) was the most suitable and Aphis gossypii Glover the least suitable, with Aphis craccivora Koch and Megoura japonica (Matsumura) intermediate. Female O. sauteri were larger than males and female body mass varied more with prey type than did that of males. Despite the variation in performance among prey, all prey species yielded equally good juvenile survival and none would be expected to negatively impact the numerical response of O. sauteri in biological control applications where these arthropods form part of the prey complex.

First fossil tooth-necked fungus beetle (Coleoptera: Derodontidae): Juropeltastica sinica gen. n. sp. n. from the Middle Jurassic of China

Chenyang CAI, John F. LAWRENCE, Adam ¦LIPIŃSKI, Diying HUANG

Eur. J. Entomol. 111 (2): 299-302, 2014 | DOI: 10.14411/eje.2014.034

The first fossil tooth-necked fungus beetle, Juropeltastica sinica gen. n. sp. n., is described and illustrated based on a single impression fossil from the Middle Jurassic Daohugou beds (ca. 165 Ma) of northeastern China. It represents the first definitive fossil belonging to the extant family Derodontidae. Juropeltastica is placed in Derodontidae based on its overall body shape and size, head with complex systems of tubercles and grooves, pronotum with dentate lateral carinae, open mesocoxal cavities bordered by mesepimeron and metanepisternum, excavate metacoxae, and 5-segmented abdomen. The occurrence of a reliable derodontid fossil from 165 million years ago places Derodontidae among the small but growing number of beetle families of known Middle Jurassic age, which is important in the dating of phylogenetic trees.

Rearing of Microplitis mediator (Hymenoptera: Braconidae) and its host Mamestra brassicae (Lepidoptera: Noctuidae)

Elodie BELZ, Céline E. GÉNEAU, Moritz FÜRST, Oliver BALMER, Pius ANDERMATT, Lukas PFIFFNER, Léon WESTERD, Henryk LUKA

Eur. J. Entomol. 111 (3): 443-447, 2014 | DOI: 10.14411/eje.2014.043

Establishing continuous and reliable colonies of pest-parasitoid systems in the laboratory is an essential requirement for carrying out manipulative experiments on biological control. Here we describe in detail the rearing protocols that we optimized for the efficient rearing of the cabbage moth Mamestra brassicae and its key parasitoid Microplitis mediator.

Comparison of the exotic and native ant communities (Hymenoptera: Formicidae) in urban green areas at inland, coastal and insular sites in Spain

Joaquín REYES-LÓPEZ, Soledad CARPINTERO

Eur. J. Entomol. 111 (3): 421-428, 2014 | DOI: 10.14411/eje.2014.044

Currently the introduction and spread of invasive species is an issue of great concern. To effectively manage this problem it is essential to know what constitute invasion hotspots. In this respect, the role of urban green areas in the conservation of biodiversity is a controversial matter. These areas may either favour colonization by alien species or shelter species of high conservation value. We evaluated the influence of location (island, coastal or inland) on the exotic and native ant fauna recorded in 27 urban green areas in Spain. A forward-stepwise discriminant analysis revealed differences between these locations in terms of the composition of the fauna, with exotic species identified as being the most important discriminating variable. There is a gradient: inland-coastal-island, along which there is significant increase in importance in terms of species richness and abundance of particular exotic species and decrease in the dominance of both common and rare native species. Areas located on the Island were more susceptible to invasion by alien ants. Coastal areas were also more susceptible to invasion than inland areas. These results possibly reflect the greater probability of an invasive species reaching these locations and the milder weather conditions at these sites, which would favour their establishment.

Bioluminescent assay for evaluating antimicrobial activity in insect haemolymph

Libor VOJTEK, Pavel DOBE©, Ender BÜYÜKGÜZEL, Janne ATOSUO, Pavel HYR©L

Eur. J. Entomol. 111 (3): 335-340, 2014 | DOI: 10.14411/eje.2014.045

We describe an antibacterial assay based on bioluminescence of two Gram negative bacteria, Photorhabdus luminescens and transformed Escherichia coli, which can be used as a real-time measurement of antibacterial activity in insect haemolymph. This method is based on the production of the bioluminescence signal depending on the viability of bacterial cells. We observed a significant rapid dose-dependent decrease in bioluminescence using both bacterial species, and Bombyx mori or Galleria mellonella haemolymph, which was confirmed by the decrease in bacterial viability determined by plating. The humoral origin of the antibacterial activity observed in whole haemolymph was confirmed for haemolymph plasma without haemocytes. Antibacterial activity directed against Gram negative bacteria was recorded in unaffected insect larvae as well as after septic injury; increased antibacterial activity of haemolymph was detected in the latter case confirming the inducibility of antimicrobial agents. We think it is likely that this method could be widely used for determining antibacterial activity in insects and other invertebrates.

Stage specific consumption and utilization of aphids, conspecific and heterospecific eggs by two species of Coccinella (Coleoptera: Coccinellidae)

Bhupendra KUMAR, Mahadev BISTA, Geetanjali MISHRA, OMKAR

Eur. J. Entomol. 111 (3): 363-369, 2014 | DOI: 10.14411/eje.2014.046

The nutritive quality of aphids, conspecific and heterospecific eggs as food for ladybirds is a controversial issue. If ladybirds find aphids more palatable than eggs then they are more likely to efficiently exploit and be biocontrol agents of aphids. If eggs of conspecific or heterospecific ladybirds are more palatable than aphids these biocontrol agents may either impede aphid pest suppression or become a threat to other species of ladybirds. Thus, prior to formulating predatory guilds of ladybirds the nutritive quality of their eggs compared to that of the target aphid needs to be determined. In this regards, the present study evaluates the nutritive quality of an ad libitum supply of: (i) pea aphid, Acyrthosiphon pisum (Harris), (ii) conspecific eggs and (iii) heterospecific eggs as food for Coccinella septempunctata (L.) and Coccinella transversalis Fabricius (Coleoptera: Coccinellidae), by determining the stage specific predation and developmental attributes of these two ladybirds reared on these diets. The conversion efficiencies and growth rates of young (first, second and third) larvae of both species of ladybirds were higher than those of fourth instar larvae and the consumption rates of fourth instar were higher than those of young larvae when fed on the three diets. When fed aphids the pre-imaginal development was faster, the consumption rates, conversion efficiencies and growth rates higher, adults bigger and mortality lower than when fed on conspecific eggs. The larvae of C. septempunctata consumed and completed their development when fed eggs of C. transversalis but the first instar larvae of C. transversalis did not consume the eggs of C. septempunctata and died of starvation. The dominance of C. septempunctata over C. transversalis in agricultural fields may be due to it consuming and utilizing aphids more efficiently and as a consequence growing faster and suffering a lower mortality along with its ability to consume and complete its development on eggs of C. transversalis. Thus, both these predators may not continue to coexist as predators of the pea aphid in agricultural fields since C. septempunctata may become a greater threat to C. transversalis in the future.

Differences between beetle communities colonizing cattle and horse dung

Radosław MROCZYŃSKI, Karol KOMOSIŃSKI

Eur. J. Entomol. 111 (3): 349-355, 2014 | DOI: 10.14411/eje.2014.050

Piles of fresh cow and horse dung were placed in a pasture in Dziarny in north-east Poland. The differences between the beetle communities colonizing both types of dung at various stages of succession were analyzed. Beetles were sampled 2, 5, 10, 15, 20 and 25 days after placing the piles of dung in the pasture. A total of 5 343 individuals belonging to 125 species and 10 families were collected in 24 samples. None of the species of beetles collected colonized exclusively one type of dung. Several taxa showed a clear preference for cow or horse dung. Beetle succession proceeded faster in horse dung and there were significant differences in the dominant species recorded in the two types of dung. The reasons for the reported patterns are discussed.

Life cycle, seasonal and interannual polymorphism in a monoecious aphid Cinara mordvilkoi (Hemiptera: Aphidoidea: Lachnidae)

Roma DURAK

Eur. J. Entomol. 111 (3): 357-362, 2014 | DOI: 10.14411/eje.2014.051

This paper presents the first description of the life cycle of Cinara mordvilkoi and alary dimorphism of its males. There are 3 phases in its life cycle and during the course of a year 10 generations of parthenogenetic females are produced. The durations of development of subsequent generations over three years were recorded. C. mordvilkoi was observed to change its feeding position on its host from leaves to roots throughout the year. In the third year of this study both winged and wingless males were recorded. The fundatrix, oviparous female and the apterous and winged males are described.

Patterns of acoustic and morphometric variation in species of genus Tettigettalna (Hemiptera: Cicadidae): Sympatric populations show unexpected differences

Raquel MENDES, Vera L. NUNES, José A. QUARTAU, Paula C. SIMÕES

Eur. J. Entomol. 111 (3): 429-441, 2014 | DOI: 10.14411/eje.2014.054

Tettigettalna (Hemiptera: Cicadidae) is a genus of small sized cicadas occurring in south-western Europe, which consists of a complex of sibling species that are morphologically difficult to distinguish from each other but their calling songs can be used as the main character for their identification. These sibling species may sometimes occur in sympatry, therefore, this genus is a suitable model for addressing questions on isolation mechanisms and recognition processes. For this study, we selected T. argentata (the species with the broadest distribution) and the three other species of Tettigettalna (T. mariae, T. estrellae and T. josei) that are known to occur in sympatry with T. argentata at some locations in their distribution ranges. Thus, the present study investigates calling song and variation in external morphology in selected sympatric and allopatric populations of four species of Tettigettalna in order to determine whether there are patterns in population divergence that provide evidence of species recognition and reproductive isolation. The interspecific analysis of the calling songs showed that most time domain variables are species-specific although an overlap was found between the maximum and minimum values in T. argentata and T. mariae populations for four time domain variables. When only sympatric populations of T. argentata and T. mariae are compared, time domain variables show less variation leading to a reduced overlap between this pair of sibling species. The morphometric variables showed low interspecific variability and did not allow a complete separation of the four species, both in allopatric and sympatric populations. Sympatric populations of both T. argentata and T. mariae showed lower frequencies and bigger general body sizes than the allopatric ones. The pattern of variation found does not correspond to the pattern expected in species undergoing character displacement.

Chromosomal characteristics and evolutionary relationships of the Palearctic black fly Simulium carthusiense (Diptera: Simuliidae)

Peter H. ADLER, Gunther SEITZ

Eur. J. Entomol. 111 (4): 469-474, 2014 | DOI: 10.14411/eje.2014.066

The giant, polytene chromosomes of Simulium carthusiense Grenier & Dorier, 1959 were mapped, and all rearrangements were resolved relative to the standard banding sequence for the S. vernum group. The species is chromosomally cohesive from Austria to Spain, and is characterized by a chromocenter, two unique fixed inversions, 10 unique autosomal polymorphisms, and undifferentiated sex chromosomes. Rare individuals (3%) have two types of supernumerary chromosomes, representing the third example of a simuliid species that carries two different supernumeraries in the same individuals. Band-sequence comparisons with chromosomal outgroups indicate that S. carthusiense is the sister species of a clade that includes S. beltukovae (Rubtsov, 1956), the S. cryophilum complex, and S. urbanum Davies, 1966.

Comparison of the developmental time of Bracon hebetor (Hymenoptera: Braconidae) reared on five different lepidopteran host species and its relationship with digestive enzymes

Dorna SAADAT, Ali R. BANDANI*, Mehdi DASTRANJ

Eur. J. Entomol. 111 (4): 495-500, 2014 | DOI: 10.14411/eje.2014.069

Bracon (Habrobracon) hebetor Say is a polyphagous parasitoid of lepidopteran larvae, including those of the family Pyralidae. There are many reports that this parasitoid attacks the larvae of stored product and field crop pests. However, there is little information on the biological parameters of this parasitoid attacking different lepidopteran hosts or the effect of the hosts on the digestive enzymes of the parasitoid. Hence, in the current study the effect of different lepidopteran hosts, Ectomyelois ceratoniae, Plodia interpunctella, Ephestia kuehniella, Helicoverpa armigera and Malacosoma disstria, on the biological parameters and digestive enzymes (α-amylase and proteases) of this parasitoid were investigated. The parasitoid performed better on stored product pests, such as E. kuehniella and P. interpunctella, than field crop pests, such as H. armigera and M. disstria. For example, in terms of percentage egg hatch, rate of development, off-spring sex ratio and adult dry mass Bracon hebetor did much better when it parasitized stored product insects than field crop insects (P < 0.05). Interestingly, the quality and quantity of the proteases and α-amylase of the parasitoid larvae parasitizing stored product and field crop pests differed. The greatest activity of these enzymes was recorded in the gut of those parasitoids that were reared on stored product insects (P. interpunctella and E. kuehniella). It is concluded that stored product insects, which feed on a diet rich in sugar and glycogen, provide physiological conditions that are more suitable for the parasitoid than field crop insects, which feed on diet rich in terpenes and tannins.

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.

Generalist-specialist continuum and life history traits of Central European butterflies (Lepidoptera) - are we missing a part of the picture?

Alena BARTONOVA, Jiri BENES, Martin KONVICKA

Eur. J. Entomol. 111 (4): 543-553, 2014 | DOI: 10.14411/eje.2014.060

Abstract. Analyzing life history traits of butterfly communities and faunas frequently reveals a generalist-specialist continuum as the main gradient, where species using wide arrays of resources, with good dispersal ability and fast development are distinguished from those using specialised resources, having limited dispersal ability and developing slowly. To ascertain the validity of the generalist-specialist approach for an intermediately species-rich Central European fauna, we analyzed ten life history traits for 136 species of butterflies currently occurring in the Czech Republic, using principal correspondence analysis (PCA) and controlling for phylogeny. The main gradient extracted indeed revealed a generalist-specialist continuum, while the gradient perpendicular to the main axis distinguished between small-bodied polyvoltine species feeding on small herbaceous plants and large-bodied monovoltine species feeding on grasses or woody plants. We coin "constrained voltinism continuum" for the second gradient and argue that it reflects the effect of anti-herbivore strategies of larval host plants on butterfly development. The position of the butterflies in the PCA ordination mirrors the C-S-R (Competitors - Stress tolerators - Ruderals) strategies of their host plants. Butterflies that feed on C- and R-selected plants tend to be generalists, but differ in voltinism, whereas specialists tend to feed on S-selected plants. Regressing measures of current conservation status of individual species in the Czech Republic against the two extracted life history gradients yielded a significant but weak response for the generalist-specialist continuum and no response for the constrained voltinism continuum. The weak responses were due to a wide scatter of status measures among "mid generalists". The generalist-specialist continuum is hence a rather poor predictor of species conservation status. Species of high conservation concern are found either among specialists, or among mid generalists with low to intermediate values on the constrained voltinism axis.

Variation in the shape of the wings and taxonomy of Eurasian populations of the Calopteryx splendens complex (Odonata: Calopterygidae)

Saber SADEGHI, Henri J. DUMONT

Eur. J. Entomol. 111 (4): 575-583, 2014 | DOI: 10.14411/eje.2014.073

We used geometric morphometrics to determine variation in the morphology of the forewings of individuals in 20 populations of Calopteryx splendens s.l. in Eurasia and related these to the circum-specific taxonomy of this taxon. We found differences in shape, with the largest and smallest centroid size of the wings in adjacent northern (orientalis) and western (intermedia) populations in Iran, respectively, so isolation and relationship are not necessarily determined by distance, but often associated with the stream basin inhabited. The variation in wing shape, however, was much greater. with Populations at the eastern edge of the range (Tajikistan, Kyrgyzstan and East Kazakhstan) uniquely different. Oddly, no taxonomic name is associated with them, although they may be among the oldest representatives of the splendens complex. The European and Asian populations are in two separate clades. One of these includes insects with no to a medium-sized wing spot, which does not reach the tip of the wing (waterstoni-group), while the other includes insects with very broad wing spots, or, when short, it extends to the very tip of the wings and most females are androchrome (ancilla or intermedia group). Turkmenistan and northern Iranian population form a separate line inside this clade, which we equate with Calopteryx orientalis. South Albanian and Greek populations are in a separate branch corresponding to ssp. balcanica; two populations from Ireland and Italy form a branch that has no equivalent in traditional taxonomy, while Calopteryx xanthostoma was not identified by its wing shape. Understanding this multitude of phenotypes and the enormous amount of variation within certain populations but not in others becomes easy if one assumes there were two probable late Pleistocene waves of migration, the first of insects lacking spots that migrated east and westwards from the South Black Sea basin, the second, perhaps from the west Caspian, composed of heavily spotted insects with androchromic females. The hybridization between these two waves resulted in the current plethora of colour forms and accounts for why similar phenotypes may turn up independently in widely distant locations.

Pollen analysis of the crop contents of adult Oedemeridae (Coleoptera) in Bulgaria

Juliana ATANASSOVA, Ognyan SIVILOV

Eur. J. Entomol. 111 (4): 588-593, 2014 | DOI: 10.14411/eje.2014.068

Pollen analysis of crop samples was used to identify the food sources of species of beetles of the family Oedemeridae in Bulgaria. A total of 21 species and subspecies were examined; pollen was present in the crops of 18 of the species. Our study is the first to provide information on the food sources of four species and subspecies: Chrysanthia varipes varipes, Anogcodes seladonius turcicus, A. ruficollis and Oedemera flavicans. New data on food sources for many of the other species studied was obtained and feeding on pollen of gymnosperms and honeydew by some of the species was confirmed. Possible mechanisms for digesting pollen are discussed. There was no evidence of either the pollen germinating or being predigested in the crop of the beetles.

Editorial: 16th European carabidologists meeting, Prague 2013

Pavel SASKA

Eur. J. Entomol. 111 (5): 598-599, 2014 | DOI: 10.14411/eje.2014.092

 

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.

Thermal constants of egg development in carabid beetles - variation resulting from using different estimation methods and among geographically distant European populations

Pavel SASKA, Miroslav VLACH, Jana SCHMIDTOVÁ, Andrey V. MATALIN

Eur. J. Entomol. 111 (5): 621-630, 2014 | DOI: 10.14411/eje.2014.077

Using equations based on the law of total effective temperatures, we estimated the thermal constants (LDT, the lower development threshold, and SET, the sum of effective temperatures) of egg development for 14 populations of 13 species of carabid beetles (eight belonging to the tribe Zabrini, one to Platynini and four to Pterostichini). We compared the estimates of the thermal constants obtained using three commonly used equations (D = SET / (T - LDT); 1 / D = a + b . T, where LDT = -a / b, and SET = 1 / b; and D . T = SET + D . LDT) and two data formats: data points for all the individuals and means for each temperature. We found that, for most species, estimates of both LDT and SET of egg development obtained using the three models were similar and that using means resulted in larger standard errors (SE) than using all data points. We provide evidence for inter-correlation among the thermal constants, showing that a decrease in the estimate of one constant is accompanied by an increase in the estimate of the other constant. For seven species for which sufficient data were available we investigated the geographical variation in their thermal constants. We found significant variation in both constants for three species, in only one in one species and in three species there was no significant variation among geographically distant populations at p < 0.05. For eight out of the nine autumn-breeding species studied, egg mortality significantly increased at high temperatures. For future studies, we recommend the use of the third method (D . T = SET + D . LDT) for estimating thermal constants for several reasons: (i) it is linear (i.e., simple to compute); (ii) the thermal constants are parameters of the equation, and therefore, their SEs are directly estimated; (iii) it allows the use of all data points (i.e., reduces the SE of the estimates of thermal constants); and (iv) the thermal requirements of different species or populations can be directly compared using ANCOVA.

Prey detection in carabid beetles (Coleoptera: Carabidae) in woodland ecosystems by PCR analysis of gut contents

Lucija ©ERIĆ JELASKA, Damjan FRANJEVIĆ, Sven D. JELASKA, William O.C. SYMONDSON

Eur. J. Entomol. 111 (5): 631-638, 2014 | DOI: 10.14411/eje.2014.079

Predatory carabid beetles are important for regulating prey abundance in terrestrial ecosystems. While surveys of carabid diet have revealed many insights into trophic interactions, the high species diversity and heterogeneous developmental stages of prey identified in the gut have made further advances difficult. In addition, the carabid gut contains partially digested and mainly soft tissue parts of the prey species, difficult to identify by traditional methods. Molecular gut content analysis (MGCA) avoids these disadvantages but to date has been limited primarily to revealing pest species in agricultural fields. Here we used MGCA to screen for the presence of Lepidoptera in carabid guts, in woodland ecosystems, in both Croatia and the UK. Data on carabids positive for Lepidoptera were compared with those from previous work on the same carabid assemblages, screened for earthworms, slugs, woodlice and springtails. In both locations, the prey group most frequently detected was earthworms, followed by slugs and Lepidoptera and then finally by woodlice and springtails. The composition of the diet changed with season, carabid sex, and carabid size. In both locations, Lepidoptera were the third most frequent prey, with 27% of carabids testing positive in Croatia and 20% in UK, suggesting that carabids could be significant predators of Lepidoptera in woodland ecosystems and may potentially play an important role in controlling moth pests.

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.

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.

Old forest edges may promote the distribution of forest species in carabid assemblages (Coleoptera: Carabidae) in Croatian forests

Andreja BRIGIĆ, Marija STARČEVIĆ, Boris HRA©OVEC, Zoltán ELEK

Eur. J. Entomol. 111 (5): 715-725, 2014 | DOI: 10.14411/eje.2014.090

Boundaries between habitats are usually accompanied by transitions in the diversity and structural complexity of insect assemblages. Edge effects on carabid beetle assemblages across forest-meadow ecotones in Dinaric beech-fir forests were determined in the Gorski Kotar region of western Croatia. Carabid beetles were sampled using pitfall traps set along gradients extending 60 m from the forest edge into its interior and 60 m into the meadow. Embedded forest edges were greater than 100 years old and had a similar composition and structure of vegetation to that in the adjacent forest. A total of 20,526 individuals belonging to 66 carabid beetle species were recorded. Carabid assemblages in the ecotones were more similar to those in the forest interiors than those in the meadows. The classical edge effect hypothesis was not supported, since the ecotones were less diverse than the meadows, while the carabid assemblages of the forest interiors were the least diverse. Soil temperature, soil humidity and light intensity did not differ significantly between the ecotones and the forest interior. Therefore, embedded forest edges reduced the microclimate edge effect by providing stable microclimatic conditions for carabid assemblages similar to those in the forest interior. In addition, this enabled forest specialists and generalists to occur right up to the forest edge and maintain stable populations in the ecotone. On the other hand, ecotones acted as filters for certain forest generalist species and true barriers for most open-habitat species. This study confirmed that the structure and ages of the vegetation at edges may play a key role in determining the spatial pattern of carabid beetles across forest-meadow ecotones.

Isolation and characterization of eleven polymorphic microsatellite markers from the beneficial carabid beetle, Poecilus cupreus (Coleoptera: Carabidae), and genetic structuring among three populations from western France

Ronan MARREC, Stéphanie RUAULT, Cécile RIBOUT, Manuel PLANTEGENEST, Bertrand GAUFFRE

Eur. J. Entomol. 111 (5): 726-729, 2014 | DOI: 10.14411/eje.2014.084

Poecilus cupreus (L.) (Coleoptera: Carabidae) is a typical polyphagous predator species on arable lands. In this study, 11 polymorphic microsatellite markers were developed from genomic DNA of P. cupreus. Genotypes of 87 individuals sampled from three localities in Western France were analyzed to characterize the polymorphism at each locus. The number of alleles ranged from 3 to 20. All pairs of loci were in linkage equilibrium. The expected and observed heterozygosity ranged from 0.165 to 0.890 and 0.103 to 0.926, respectively. From the northern to the southern sites, six, three, and six loci showed significant deviations from Hardy-Weinberg equilibrium, respectively. At one locus, null alleles were suspected as occuring at high frequency in the three populations. A weak genetic differentiation among populations was found, suggesting intense and large scale gene flow coupled with large population size in P. cupreus. These polymorphic microsatellite markers could be used in future population genetics studies of P. cupreus.

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.

Aproceros leucopoda (Hymenoptera: Argidae): An East Asian pest of elms (Ulmus spp.) invading Europe

Stephan M. BLANK, Hideho HARA, József MIKULÁS, György CSÓKA, Constantin CIORNEI, Raoul CONSTANTINEANU, Irinel CONSTANTINEANU, Ladislav ROLLER, Ewald ALTENHOFER, Tomasz HUFLEJT, Gábor VÉTEK

Eur. J. Entomol. 107 (3): 357-367, 2010 | DOI: 10.14411/eje.2010.045

An invasive sawfly Aproceros leucopoda Takeuchi, 1939, which originates from East Asia, has colonized elms (Ulmus spp.) in Austria, Hungary, Poland, Romania, Slovakia and the Ukraine, at least since 2003. In Europe, the larvae can completely defoliate native and non-native elm trees and may cause at least partial dieback. Field observations indicate that elms are infested independent of their age and site characteristics. The life cycle of A. leucopoda is described based on material reared in Hokkaido, Japan. Parthenogenetic reproduction, short life cycle of summer generations and the ability to produce four generations per year result in the production of numerous progeny. The evolution of a seasonal dimorphism in head morphology, a simple cocoon that is attached directly to the host plant and a short period spent in the cocoon stage during summer, are putative apomorphies shared by Aproceros Takeuchi, 1939 and Aprosthema Konow, 1899. These traits reduce developmental costs and contribute to the proliferation of A. leucopoda. No specialized parasitoid, that can effectively reduce outbreaks of this species, is known. It is likely that this pest will spread into central and south-western Europe. Further monitoring of A. leucopoda is required to assess future range extensions in Europe, its exacerbating effect on Dutch elm disease and to find a suitable biocontrol agent. Concise keys to imaginal and larval stages are presented that will facilitate the identification of A. leucopoda.

Altitudinal distribution of moths (Lepidoptera) in Mt. Jirisan National Park, South Korea

Sei-Woong CHOI, Jeong-Seop AN

Eur. J. Entomol. 107 (2): 229-245, 2010 | DOI: 10.14411/eje.2010.031

The relationship between species richness of plants and animals and altitude can be either hump-shaped, a monotonic decrease or increase. In this study the altitudinal distribution of moths on one of the highest mountains in South Korea was investigated. Moths were captured using a UV-light trap from May to October in 2007 and 2008. This revealed that the relationship between the total numbers of moth species and individuals and altitude is hump-shaped. A significant relationship was also recorded between the size of the area at each altitude and moth abundance and richness. However, the evenness index yielded a consistent decrease with increase in altitude because of the dominance of few species at high altitudes. Non-metric multidimensional scaling identified two major axes for the moth assemblage on Mount Jirisan. The correlations between the axes and variables demonstrated that the first axis was strongly correlated with altitude and aspect and the second axis with forest and site location.

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