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A case study of Heleomyzidae (Diptera) recorded on snow in Poland with a review of their winter activity in EuropeOriginal articleAgnieszka SOSZYŃSKA-MAJ, Andrzej J. WO¬NICAEur. J. Entomol. 113: 279-294, 2016 | DOI: 10.14411/eje.2016.035 Twenty eight species of winter-active Heleomyzidae were collected during a long-term study in Poland. More than 130 samples of insects, including Heleomyzidae, were collected from the surface of snow in lowland and mountain areas using a semi-quantitative method. Lowland and mountain assemblages of Heleomyzidae recorded on snow were quite different. Heleomyza modesta (Meigen, 1835) and Scoliocentra (Leriola) brachypterna (Loew, 1873) dominated in the mountains, Tephrochlamys rufiventris (Meigen, 1830) mainly in the lowlands and Heteromyza rotundicornis (Zetterstedt, 1846) was common in both habitats. Heleomyzidae were found on snow during the whole period of snow cover, but the catches peaked from late November to the beginning of February. In late winter and early spring the occurrence of heleomyzids on snow decreased. Most individuals were active on snow at air temperatures between -2 and +2.5°C. A checklist of 78 winter active European Heleomyzidae is presented. Helomyza nivalis Wahlgren, 1918 is herein considered as a new junior synonym of Helomyza caesia Meigen, 1830, syn. n. |
Long-term partitioning of space between two territorial species of ants (Hymenoptera: Formicidae) and their effect on subordinate speciesWojciech CZECHOWSKI, Bįlint MARKÓ, Alexander RADCHENKO, Piotr ¦LIPIŃSKIEur. J. Entomol. 110 (2): 327-337, 2013 | DOI: 10.14411/eje.2013.046 Competition is a major force organizing ant communities and results in co-occurring species evolving different strategies for foraging and use of space. Territorial species, as top dominants exclude each other, while shaping the local ant communities both qualitatively and quantitatively. In this study we examined how two territorial species, Formica polyctena and Lasius fuliginosus, can coexist in adjacent territories over long periods of time, and whether they affect co-occurring species of ants in different ways. Field observations in the absence and in the presence of baits were carried out around a L. fuliginosus nest complex surrounded by a polydomous F. polyctena colony in S Finland in 2007-2009. Both species controlled their territories, but were affected by changes in the abundance of the other species and the distance from L. fuliginosus' main nest. They did not have the same effect on the subordinate species in the absence of baits, but the abundance of Myrmica spp. recorded at baits was negatively affected by both of the territorial species. The preferences of the different species for the artificial food sources differed: L. fuliginosus and F. polyctena preferred tuna to honey and Myrmica spp. honey to tuna. More individuals of the subordinate species were recorded in the territory of F. polyctena than of L. fuliginosus, although conflicts with this territorial species were also recorded. During the three years of the study almost no overlaps in the territories of the two territorial species were recorded, and there were mostly minor shifts in the boundaries of the territories. Differences between the two territorial species in their use of space and competitive effects ensured their coexistence at this particular site in Finland. |
Variation in male and female mating behaviour among different populations of the two-spot ladybird, Adalia bipunctata (Coleoptera: Coccinellidae)Penelope R. HADDRILL, Michael E.N. MAJERUS, David M. SHUKEREur. J. Entomol. 110 (1): 87-93, 2013 | DOI: 10.14411/eje.2013.011 Investigating the function of both male and female mating behaviours is essential in our attempts to understand the evolution of mating systems. Variation in mating behaviours among different populations within a species provides a useful opportunity to explore how behaviours may co-vary, although comparative studies are still rather few in number. Population variation in mating behaviour may also have important implications in terms of the evolution of reproductive isolation, the distribution of genetic diversity within and between populations, and the associated ability of those populations to adapt. Here we consider male and female mating behaviour in two populations of the two-spot ladybird, Adalia bipunctata, from the UK and Russia. We find that male and female mating behaviours differ between the populations in terms of the length of female rejection behaviour and the duration of mating, and that this variation is independent of which population an individual's mating partner is from. Our data confirm that patterns of sexual selection and reproductive behaviour are likely to vary across populations in the two-spot ladybird. The extent to which this variation is due to current ecological factors or population history remains to be verified for this species, as for many others. |
Surveying abundance and stand type associations of Formica aquilonia and F. lugubris (Hymenoptera: Formicidae) nest mounds over an extensive area: Trialing a novel methodKerry M. BORKIN, Ron W. SUMMERS, Len THOMASEur. J. Entomol. 109 (1): 47-53, 2012 | DOI: 10.14411/eje.2012.007 Red wood ants are ecologically important members of woodland communities, and some species are of conservation concern. They occur commonly only in certain habitats in Britain, but there is limited knowledge of their numbers and distribution. This study provided baseline information at a key locality (Abernethy Forest, 37 km2) in the central Highlands of Scotland and trialed a new method of surveying red wood ant density and stand type associations: a distance sampling line transect survey of nests. This method is efficient because it allows an observer to quickly survey a large area either side of transect lines, without having to assume that all nests are detected. Instead, data collected on the distance of nests from the line are used to estimate probability of detection and the effective transect width, using the free software "Distance". Surveys took place in August and September 2003 along a total of 71.2 km of parallel, equally-spaced transects. One hundred and forty-four red wood ant nests were located, comprising 89 F. aquilonia (Yarrow, 1955) and 55 F. lugubris (Zetterstedt, 1838) nests. Estimated densities were 1.13 nests per hectare (95% CI 0.74-1.73) for F. aquilonia and 0.83 nests per hectare (95% CI 0.32-2.17) for F. lugubris. These translated to total estimated nest numbers of 4,200 (95% CI 2,700-6,400) and 3,100 (95% CI 1,200-8,100), respectively, for the whole forest. Indices of stand selection indicated that F. aquilonia had some positive association with old-growth and F. lugubris with younger stands (stem exclusion stage). No nests were found in areas that had been clear-felled, and ploughed and planted in the 1970s-1990s. The pattern of stand type association and hence distribution of F. aquilonia and F. lugubris may be due to the differing ability to disperse (F. lugubris is the faster disperser) and compete (F. aquilonia is competitively superior). We recommend using line transect sampling for extensive surveys of ants that construct nest mounds to estimate abundance and stand type association. |
Molecular analysis of the gut contents of Harmonia axyridis (Coleoptera: Coccinellidae) as a method for detecting intra-guild predation by this species on aphidophagous predators other than coccinellidsBrecht INGELS, Alexandre AEBI, Louis HAUTIER, Thomas VAN LEEUWEN, Patrick DE CLERCQEur. J. Entomol. 110 (4): 567-576, 2013 | DOI: 10.14411/eje.2013.077 Several studies have demonstrated that the invasive ladybird Harmonia axyridis is a strong intra-guild predator of native species of ladybird. Laboratory studies have shown that H. axyridis can be an intra-guild predator of aphid predators other than coccinellids, including the hoverfly Episyrphus balteatus and lacewing Chrysoperla carnea. However, little is known about the effect of intra-guild predation (IGP) by H. axyridis on hoverfly and lacewing populations in the field. In the present study molecular analyses were used to detect the DNA of E. balteatus and C. carnea in the gut contents of H. axyridis. Primers for the syrphid and chrysopid prey were designed and feeding experiments performed to determine how long prey DNA remains detectable in the guts of this ladybird. DNA detection was influenced by the life stage of the predator and species of prey. Meal size did not affect detection time, except when fourth instar individuals of H. axyridis were fed 10 eggs or one second instar of C. carnea. Predator weight, sex and morpho-type (melanic/non-melanic) did not influence DNA detection. The half-life of the time for which the DNA of the prey remained detectable was calculated for each predator-prey combination, and ranged from 8.9 to 52.4 h. This method can be used to study the ecological importance of IGP by H. axyridis on aphidophagous predators other than coccinellids in the field. |
The influence of changes in viticulture management on the butterfly (Lepidoptera) diversity in a wine growing region of southwestern GermanyThomas SCHMITT, Bettina AUGENSTEIN, Aline FINGEREur. J. Entomol. 105 (2): 249-255, 2008 | DOI: 10.14411/eje.2008.035 Viticulture is one of the most intensively managed agricultural ecosystems in Europe. Therefore, the conservation problems of vineyards and the ecological benefits of increasing the amount of fallow land are addressed using butterflies as a model group. We established 43 transects, each 100 m long, in a vineyard region in the vicinity of Trier (Rhineland-Palatinate, Germany) and recorded the butterflies observed along these transects on 20 occasions from late May to early August 2003. Transects crossed vineyards, fallow land and transitional areas of land. 4041 individuals of 34 species showed the typical pattern of relative abundance with few common and many relatively rare species. Fallow land had more individuals and species and a higher Shannon species diversity index than vineyards. Community evenness and average butterfly dispersal ability were highest in the vineyards. Principal Factor Analyses and UPGMA cluster analysis distinguished between fallow land and vineyards. The difference between early meadow and late forest fallow land areas was not strong, but the former tended to have a higher diversity than the latter. Vineyards thus might act as a sink for butterflies. Therefore, a clear separation between vineyards and fallow land is best for nature conservation. As young fallow land tends to have a higher diversity than older fallow land in this study, it is likely that the conservation value of vineyards for butterflies could be increased by active management of fallow land areas. |
Is host age an important factor in the bionomics of Apanteles myeloenta (Hymenoptera: Braconidae)?Hossein Kishani FARAHANI, Seyed Hossein GOLDANSAZEur. J. Entomol. 110 (2): 277-283, 2013 | DOI: 10.14411/eje.2013.041 The carob moth, Ectomyelois ceratoniae (Lepidoptera: Pyralidae), is a serious pest and causes a considerable loss of yield of pomegranate in Iran. Apanteles myeloenta (Hymenoptera: Braconidae) is the dominant parasitoid of this pest parasitizing it more than 30% in recent years. This parasitoid is a candidate for augmentative biological control program to reduce the level of the infestation of fruit overwinter. The objective of this research was to optimize the mass production of A. myeloenta. The mean developmental time of females was 28 days and of males 27 days. Pupal development lasted 7 days. The second instar was the preferred host and most heavily parasitized (45%). Wasps that started their development in second instar hosts produced the highest progeny and those that started in third instar hosts survived as adults for longest. The sex ratio (females to males) of A. myeloenta that emerged from carob moth larvae parasitized in the first instar was 1 : 3.5, in the second instar 1 : 3 and in the third instar 1 : 2. The influence of different host ages on the functional response of A. myeloenta to host density was assessed. Logistic regression indicated a type II functional response to different densities of all the stages of the host tested. |
Gas exchange patterns in Platynus assimilis (Coleoptera: Carabidae): Respiratory failure induced by a pyrethroidIrja KIVIMÄGI, Aare KUUSIK, Angela PLOOMI, Luule METSPALU, Katrin JÕGAR, Ingrid H. WILLIAMS, Ivar SIBUL, Külli HIIESAAR, Anne LUIK, Marika MÄNDEur. 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. |
Termites (Isoptera) from the Jurassic/Cretaceous boundary: Evidence for the longevity of their earliest generaPeter VR©ANSKŻ, Danil ARISTOVEur. J. Entomol. 111 (1): 137-141, 2014 | DOI: 10.14411/eje.2014.014 The earliest termite of the extant genus Mastotermes, is herein recorded in the Jurassic/Cretaceous (J/K) transitional beds of Chernovskie Kopi in Transbaikalian Russia along with Santonitermes of an uncertain family. These records represent the earliest eusocial organisms. No termites have ever been recorded among the hundreds of thousands of fossil insects in the Jurassic/Cretaceous boundary Beds of China and Mongolia or in prior time periods. Both genera indicate that the early termites survived for an extremely long period of time. The present find both provides evidence of the greatest ghost range (60 Mya) of any winged stem cockroach family and indicates that the origin of termites and evolution of eusociality occurred later than the Middle Jurassic. |
Suitable food plants for mass rearing of the short-horn grasshopper Oxya hyla hyla (Orthoptera: Acrididae)Subhasish GHOSH, Parimalendu HALDAR, Dipak K. MANDALEur. J. Entomol. 111 (3): 448-452, 2014 | DOI: 10.14411/eje.2014.038 Acridids could be an alternative source of protein for feeding to livestock as large numbers can be produced by rearing them on suitable food plants under optimum environmental conditions. The aim of the present study was to find a suitable food plant for the mass culture of the short-horn grasshopper Oxya hyla hyla (Serville). Food consumption and utilization, growth (growth rate, average daily growth, specific growth rate and wet weight gain), survival and life span of this insect reared on Sorghum halepense, Cyanodon dactylon and a mixture of these two plants were determined. The result revealed that the food utilization, growth and survival of this grasshopper depended on the food plant. The nymphs that were reared on C. dactylon consumed less food but had a greater efficiency of conversion of ingested food to body mass, growth performance and survival than those feed on the other two types of food. In contrast, the food consumption and utilization, growth and weight gain of adult grasshoppers was greatest when they were reared on S. halepense. These results indicate that of the plants used in this study C. dactylon is the best for rearing the nymphs and S. halepense for rearing the adults of Oxya hyla hyla. |
Resources for British butterflies (Lepidoptera: Hesperioidea, Papilionoidea). The alien consumer component and its significance for butterfly habitatsPeter B. HARDY, Roger L.H. DENNISEur. J. Entomol. 105 (4): 649-657, 2008 With climatic warming there is an expectation that phytophagous insects will increasingly use alien (non native) plants as nectar sources and larval host plants. Alien plant use is investigated in British butterflies. Butterflies are considered to be larval host plant specialists relative to their use of nectar plants. Supporting this view, use of alien plants as nectar sources (50.1%, 27 novel plant families) is almost twice that of their use as larval host plants (21.6%; three novel plant families). Some 80% of the variation in percent alien nectar plant use is accounted against 30% of that for percent alien host plant use. The key variable accounting for alien plant use is butterfly mobility. Other prominent variables that facilitate access to alien nectar plants are southern distributions, longer adult life span, host plants in garden biotopes. A different set of variables additionally account for alien host plant exploitation (% alien host plant use: woody host plants; number of alien host plants: polyphagy; greater abundance of native host plants in gardens). Although threatened butterfly species do not depend on alien plants, this may well reflect on specialisation in resource use accompanying habitat fragmentation and an inability to use novel resources that are becoming increasingly available. Detailed study of alien resources is advocated to assess the importance of alien plant resources for phytophagous insects. |
The microspatial distribution of beetles (Coleoptera) on exposed riverine sediments (ERS)Adam J. BATES, Jon P. SADLER, Joe N. PERRY, Adrian P. FOWLESEur. J. Entomol. 104 (3): 479-487, 2007 | DOI: 10.14411/eje.2007.068 Exposed Riverine Sediments (ERS) are often characterised by a high diversity of microhabitats due to strong lateral gradients in temperature, humidity, inundation frequency and availability of aquatic food resources and to variations in the degree of vegetation cover, sediment size and sorting. This variation, potentially in combination with interspecific competitive interactions, is thought to drive the microspatial distribution of ERS invertebrates. This research investigated the microspatial distribution of six ERS specialist beetles across three discreet patches of ERS. In particular it examined the temporal stability of species distributions, and their spatial association with environmental variability and other species. The research used a grid of 204 modified dry pitfall traps over six sampling periods in which weather conditions and water levels were stable, and used the Spatial Analysis by Distance IndicEs (SADIE) method to test the significance of spatial distributions and associations. Strong and significant microspatial zonation was observed for all species, and with few exceptions these distributions were remarkably stable across the study period. This zonation was mainly associated with elevation and proximity to the water, and several species were consistently spatially associated or disassociated with one another. This suggests that laterally more extensive patches of ERS support more species. Operations that reduce the size of ERS patches, such as channelisation, aggregate extraction and regulation are therefore likely to reduce ERS invertebrate diversity. |
Forest moth assemblages as indicators of biodiversity and environmental quality in a temperate deciduous forestJeong-Seop AN, Sei-Woong CHOIEur. 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. |
Cytogenetic variability among Bradyporinae species (Orthoptera: Tettigoniidae)Elæbieta WARCHA£OWSKA-¦LIWA, Beata GRZYWACZ, Anna MARYAŃSKA-NADACHOWSKA, Tatyana V. KARAMYSHEVA, Dragan P. CHOBANOV, Klaus-Gerhard HELLEREur. 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. |
Utilization of the nutrients in the soluble and insoluble fractions of fungal mycelium by larvae of the stag beetle, Dorcus rectus (Coleoptera: Lucanidae)Masahiko TANAHASHI, Kōhei KUBOTAEur. J. Entomol. 110 (4): 611-615, 2013 | DOI: 10.14411/eje.2013.083 Larvae of the stag beetle, Dorcus rectus, feed on decaying wood, which they digest with the aid of symbiotic yeasts; however, they can be successfully reared on artificial diets containing only fungal tissue. In this study we tested whether D. rectus larvae can utilize fungal cell walls, which are an insoluble component of mycelium. Lyophilized Bjerkandera adusta mycelium cultured in potato-dextrose liquid medium consisted of a 47.6% hot-water insoluble fraction by mass, which contains 53.7% of the total nitrogen in the mycelium. D. rectus larvae that hatched from surface-sterilized eggs were reared for 14 days on agar-based diets containing either the soluble fraction, insoluble fraction or both, extracted from 100 mg of mycelium. The larvae increased in mass most on the mixed diet, and there was no difference in their growth on the mixed and positive control diets. Both the soluble and insoluble fractions improved larval growth compared to the negative control diet; however, the growth rates were much lower than those expected from the nitrogen dose-growth response curve obtained in a previous study. Addition of b-chitin to the soluble fraction did not positively affect larval growth. Therefore, we conclude that (1) D. rectus larvae need both the soluble and insoluble fractions of mycelium and (2) the larvae digest the insoluble fraction using their own enzymes. |
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 RASEKHEur. 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. |
The presence of micropyles in the shells of developing and undeveloped eggs of the ladybird beetle Harmonia axyridis (Coleoptera: Coccinellidae)Naoya OSAWA, Arata YOSHINAGAEur. J. Entomol. 106 (4): 607-610, 2009 | DOI: 10.14411/eje.2009.076 In Hymenoptera and Heteroptera, the absence of micropyles is one criterion for categorizing an egg as trophic. Undeveloped eggs are observed in more than 90% of the egg clusters of the ladybird beetle Harmonia axyridis Pallas. Traditionally, these undeveloped eggs are regarded as "trophic eggs." The surfaces of the eggs of H. axyridis were examined using scanning electron microscopy and the presence of micropyles in the shells of developing and undeveloped eggs determined. Micropyles are circularly distributed around the top of eggs and present in both developing and undeveloped eggs. The number of micropyles in the shells of developing and undeveloped eggs did not differ significantly. Our results indicate that the undeveloped eggs of H. axyridis have micropyles, suggesting that the mechanisms regulating the production of undeveloped eggs in H. axyridis differ from those resulting in the production of trophic eggs by Hymenoptera and Heteroptera. |
Application of the mean individual biomass of ground beetles (Coleoptera: Carabidae) to assess the assemblage successions along areas of recent glacier retreatsMauro GOBBIEur. J. Entomol. 111 (4): 537-541, 2014 | DOI: 10.14411/eje.2014.071 Glacial retreat creates new habitat which is colonized by plants and animals during the process of primary succession. Traditionally, invertebrate succession along the glacier forelands has been spatially and temporally described by the following predictors: species richness, diversity/similarity indices and species traits. In this paper another approach is used and applied to carabid beetle assemblages in two alpine glacier forelands. It utilizes mean individual biomass (MIB), which is considered by several authors to be a good indicator of habitat successional stages. MIB increased with time since deglaciation and this is related to species turnover along the glacier forelands. Specifically, MIB is able to separate early from late successional stages. The former are characterized by carabid assemblages with low MIB values and species typical of pioneer habitats, while the latter are characterized by carabid assemblages with high MIB values and species typical of stable and mature habitats. Therefore, MIB seems to be a sensitive indicator of carabid beetle successional stages also along the glacier forelands. |
Key factors affecting the predation risk on insects on leaves in temperate floodplain forestMichaela DROZDOVĮ, Jan ©IPO©, Pavel DROZDEur. J. Entomol. 110 (3): 469-476, 2013 | DOI: 10.14411/eje.2013.062 The predation on insects on leaves was measured by direct observation using live larvae of Calliphora vicina (Diptera: Calliphoridae) as bait placed on 15 common species of woody plants in a floodplain forest in the temperate region. The predation rate was measured in terms of the proportion of the larvae that were missing or had been attacked after 30 min of exposure on leaves. Despite the fact that the important predators differed during the course of a season, the most frequently recorded predators were birds and ants and less frequently recorded wasps and spiders. Analysis of the pattern in the distribution of the attacks confirmed that it is best described by a negative binomial distribution, which corresponds to a clumped dispersal of predation. Based on the results of the best-fitted generalized additive model, we could not reject an equal probability of attacks on the different species of woody plants. Further, predation at the forest edge was notably higher than in the forest interior. The model also predicted marked variations in the incidence of attacks during the course of a day and a season, with the attacks occurring mainly in three periods during the year and two during the day. In general, the sampling method used could become the standard measure of the risk of insects living on trees being attacked by predators in future studies. |
Immunomodulation in insects post-treatment with abiotic agents: A reviewEl-Sayed H. SHAURUBEur. J. Entomol. 109 (3): 303-316, 2012 The effects of different abiotic agents that may modulate the activity of an insect's immune system are reviewed. These agents include insecticides, chitin synthesis inhibitors, juvenile hormone analogues, inert particles, antibiotics, heavy metals, radiation and miscellaneous substances. The significance of studying immunomodulation in insects treated with abiotic agents in relation to both insect control and insect-borne parasitic diseases and the link between immunomodulation in insects post-treatment with both abiotic and biotic agents are discussed. |
Comparison of the developmental time of Bracon hebetor (Hymenoptera: Braconidae) reared on five different lepidopteran host species and its relationship with digestive enzymesDorna SAADAT, Ali R. BANDANI*, Mehdi DASTRANJEur. 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. |
Dispersal of individuals of the flightless grassland ground beetle, Carabus hungaricus (Coleoptera: Carabidae), in three populations and what they tell us about mobility estimates based on mark-recaptureZoltan ELEK, Lukį¹ DRAG, Pavel POKLUDA, Lukį¹ ČĶ®EK, Sįndor BÉRCESEur. J. Entomol. 111 (5): 663-668, 2014 | DOI: 10.14411/eje.2014.080 Knowledge of the dispersal ability of endangered species is crucial for developing effective, evidence-based conservation policies. Due to their limited dispersal abilities and specific habitat requirements, insects are among the animals most threatened by habitat fragmentation. We studied three populations of the highly endangered species of ground beetle, Carabus hungaricus, at three sites in Central Europe (Hungary and Czech Republic) using mark-release-recapture (MRR). The total catch of 574 pitfall traps set at the three sites was 6255 individuals. Depending on the site, the percentage recaptured was 13-32%. Average and maximum distance moved by individuals of both sexes at each of the sites ranged between 47-132 and 207-1104 m, respectively. The probability of the movements following an inverse power function (IPF) for the two sexes did not differ, but did differ among sites. Probability of dispersing for distances >100 m differed by an order of magnitude between sites, most likely because of differences in how the samples were collected. Despite the fact that individual beetles are able to move over distances in the order of kilometres, the high fragmentation of their habitats is likely to prevent them from colonizing most uninhabited habitat patches. Therefore, the conservation of this threatened ground beetle could be improved by adopting and implementing a policy of assisted dispersal. Our results from three study sites also provide an interesting illustration of the variability in the estimates of the probability of dispersal obtained using MRR. |
Comparative study of mtDNA in species of the genus Adalia (Coleoptera: Cocinellidae) and origin of ancient mitochondrial haplotypes in the gene pool of Adalia bipunctataIlya ZAKHAROV, Elena SHAIKEVICHEur. J. Entomol. 110 (3): 427-433, 2013 | DOI: 10.14411/eje.2013.057 Fifteen different mitochondrial haplotypes of the mtDNA gene COI encoding cytochrome C oxidase subunit I were identified in the 127 individuals of Adalia bipunctata studied. Two mitochondrial haplotypes, H9 and H10, differed greatly from the others. The mitochondrial polymorphism in A. bipunctata is ancient, though its age remains to be evaluated. It is shown that mitochondrial haplotypes H9 and H10 and others coexisted in the original population of A. bipunctata before it spread throughout Eurasia from Western Europe to the Baikal Area, and before the differentiation of the subspecies A. bipunctata fasciatopunctata, which differs from the European form in its elytral pattern. In order to evaluate the possible origin of the ancient mitochondrial haplotypes in the gene pool of A. bipunctata sequences of the mtDNA gene COI and of the rRNA second internal transcribed spacer of the four species of Adalia: A. bipunctata, A. decempunctata, A. frigida and A. tetraspilota, were compared. It is suggested that infection with Rickettsia had an important role in the preservation of the mitochondrial haplotypes H9 and H10 during the evolution of Adalia. |
Occurrence of Harmonia axyridis (Coleoptera: Coccinellidae) in field cropsAxel VANDEREYCKEN, Yves BROSTAUX, Emilie JOIE, Eric HAUBRUGE, Franēois J. VERHEGGENEur. J. Entomol. 110 (2): 285-292, 2013 | DOI: 10.14411/eje.2013.042 The Multicoloured Asian Ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae) is known to thrive principally in shrubby and arboreal habitats. This study focuses on the occurrence of this exotic species and its seasonal abundance in various field crops. The abundance of adults, larvae and pupae of H. axyridis was evaluated over a three-year period, from 2009 to 2011, in four important agronomical crops (wheat, corn, broad bean and potato) in Belgium. From May to September, 48 1-m2 quadrats were visually inspected in each of the fields sampled on several farms every seven days. H. axyridis colonized and reproduced in all of the four crops studied, with the largest numbers recorded in corn and broad bean crops. Larvae and adults of H. axyridis were recorded mainly in corn and to a much less extent in wheat and potato crops. From 2009 to 2011, the mean weekly abundance of H. ayxridis remained constant except in corn crops, where the recorded densities of all the immature stages and adults were higher in 2011 than in 2009. The population dynamics of aphids and H. axyridis are well described by a symmetric logistic function (S-shape) of cumulative population size. H. axyridis was not always recorded where aphids were abundant, e.g. aphids were abundant on wheat where no H. axyridis were recorded. H. axyridis start reproducing after the peak in aphid population, suggesting that H. axyridis is able to complete its development by feeding on alternative prey such as larvae and pupae of the same and other species of ladybird and other aphidophagous species. H. axyridis is often considered to be bivoltine but it only completes one generation per year in field crops. The second generation generally develops late in the season in other habitats. |
Response of Lymantria dispar (Lepidoptera: Lymantriidae) larvae from differently adapted populations to allelochemical stress: Effects of tannic acidMarija MRDAKOVIĘ, Vesna PERIĘ MATARUGA, Larisa ILIJIN, Milena VLAHOVIĘ, Milena JANKOVIĘ TOMANIĘ, Dejan MIRČIĘ, Jelica LAZAREVIĘEur. J. Entomol. 110 (1): 55-63, 2013 | DOI: 10.14411/eje.2013.007 The effects of tannic acid on mean values and genetic variation in fitness-related traits (mass, relative growth rate) and specific activities of digestive enzymes (total proteases, a-glucosidase and lipase), and genetic variation in their plasticity, were investigated in fifth instar larvae of Lymantria dispar L. (Lepidoptera: Lymantriidae) originating from two populations with different host use histories (oak and locust-tree). The two populations did not differentiate with respect to fitness-related traits, i.e. adverse effects of tannic acid were similar in both populations. However, Robinia larvae, which originated from the locust-tree forest, were characterized by higher total protease and lipase activity and lower a-glucosidase activity than Quercus larvae, which originated from the oak forest. Higher plasticity of lipase and lower plasticity of a-glucosidase in response to tannic acid were also recorded. Quantitative genetic analysis revealed mostly significant expression of genetic variation in the examined traits and trait plasticity, suggesting the potential for evolution of adaptive plastic responses to new environmental conditions and presence of a stressor. The genetic correlations observed between the environments significantly differed from "one", which indicates there are no constraints on the evolution of trait plasticity. |
Pollen resources used by Chrysoperla agilis (Neuroptera: Chrysopidae) in the Azores, PortugalLeila NUNES MORGADO, Roberto RESENDES, Mónica MOURA, Maria A. MATEUS VENTURAEur. J. Entomol. 111 (1): 143-146, 2014 | DOI: 10.14411/eje.2014.015 There are approximately 1200 described species of Chrysopidae, many of which are predators of agricultural pests. Species of Chrysoperla are mass-produced and sold for use as biological control agents of agricultural pests in Europe, Asia, North and South America. Chrysoperla agilis, a member of the "carnea group" of Chrysoperla, has the potential to be biocontrol agent and is native to the Azores, and therefore a local candidate for use in IPM of pests, such as aphids and scale insects. Given that many adult Chrysopidae feed on pollen and honeydew and the biology of Ch. agilis is not well understood, we studied the preferences of Ch. agilis adults living in a greenhouse on the campus of the University of the Azores for feeding on different types of pollen. Twenty-six species of flowering plants, belonging to 16 families and 24 genera, all previously recorded on Sao Miguel Island, were found in the greenhouse. Pollen grains from each species were collected and incorporated in a reference catalogue. Additionally, 40 adults of Ch. agilis were collected (20 in December 2012 and 20 in January 2013) and the pollen in guts identified. Of the 26 species of plants in the greenhouse 14 were used as sources of pollen by the lacewings. Pollen of Plantago lanceolata L. was the most frequently recorded pollen in the gut contents. The adults of this chrysopid fed mainly on the pollen of species of plants belonging to the Asteraceae, Plantaginaceae and Poaceae. The species richness (S = 12), diversity index (H' = 2.123) and equitability (J' = 0.8543) of the January sample are greater than those of the December sample. Similarity of the samples collected in the 2 months was 0.75. From these results we infer that it is important to maintain or increase plant biodiversity in agroecosystems as weeds provide trophic resources for insects that are beneficial to agriculture. |
First cytogenetic study of Coleorrhyncha: Meiotic complement of Xenophyes cascus (Hemiptera: Peloridiidae)Snejana GROZEVA, Valentina KUZNETSOVA, Viktor HARTUNGEur. J. Entomol. 111 (2): 303-306, 2014 | DOI: 10.14411/eje.2014.023 Cytogenetic information on the hemipteran suborder Coleorrhyncha is here provided for the first time. The New Zealand peloridiid species, Xenophyes cascus Bergroth, 1924 (Hemiptera: Coleorrhyncha: Peloridiidae), was found to display testes with a single follicle each, holokinetic chromosomes (like other Hemiptera), a karyotype of 2n = 26 + X(0) and a single chiasma per bivalent in male meiosis. Comparative analysis of sex chromosome systems in all four hemipteran suborders (Sternorrhyncha, Auchenorrhyncha, Heteroptera and Coleorrhyncha) allowed inference that an X(0) sex determining system was ancestral within the Hemiptera, whilst the XY-system was most likely a derived condition within the Heteroptera. |
Sex ratio distortion in the Nesolynx thymus (Hymenoptera: Eulophidae), an ecto-pupal parasitoid of uzifly, Exorista sorbillans (Diptera: Tachinidae)Bandekodigenahalli M. PRAKASH, Aswathaiah PRATHIMA, Hoolageri C. HUCHESH, Hemagirigowda RAVIKUMAR, Shankaranarayan SAMPATHKUMAR, Hosagavi P. PUTTARAJUEur. J. Entomol. 111 (4): 453-456, 2014 | DOI: 10.14411/eje.2014.059 The reproductive alterations induced by maternally inherited α-proteo-bacteria Wolbachia to their hosts is a well-documented phenomenon. In Nesolynx thymus, a gregarious hymenopterous ecto-pupal parasitoid of the uzifly, Exorista sorbillans, diagnostic PCR assay using specific primers revealed the presence of Wolbachia. Following genetic crossing experiments, we observed a female biased sex ratio of 1 : 9.5 at 25°C and 1 : 3 male to female ratio when the populations were exposed to heat shock 33°C for six hours. Furthermore, we found infection polymorphism, where female parasitoids are infected by Wolbachia but males are not infected. Infected eggs develop into females, whereas uninfected eggs develop parthenogenetically into males. The results are discussed in the context of the possible mechanism of sex-ratio bias caused by Wolbachia. |
The genetic architecture of extended life span in the seed beetle Acanthoscelides obtectus (Coleoptera: Bruchidae)Darka ©E©LIJA, Nikola TUCIĘEur. J. Entomol. 105 (4): 553-560, 2008 We studied the genetic architecture of the differences in the longevity between lines selected for postponed senescence and a control population of the seed beetle Acanthoscelides obtectus maintained on two hosts. By using lines with increased longevity, which were obtained by selection on natural variation in longevity, we showed that the genetic architecture of seed beetle longevity is complex, with sex-specific effects and variation attributable to many interacting genes, whose expression depend on the host on which the beetles were reared. The nonadditive genetic effects were more strongly expressed when reared on chickpeas, a novel host, than on beans. Outbreeding depression, with respect to longevity, was a consequence of both the intrinsic effect of interactions between genes from different parental sources (disruption of coadapted gene complexes) and the genotype × host interaction (loss of local adaptation). |
Behavioural and toxicological responses of Blattella germanica (Dictyoptera: Blattellidae) to monoterpenesRaśl A. ALZOGARAY, Valeria SFARA, Ariadna N. MORETTI, Eduardo N. ZERBAEur. J. Entomol. 110 (2): 247-252, 2013 | DOI: 10.14411/eje.2013.037 Certain monoterpenes produced by aromatic plants are known to have lethal and sublethal effects on insects. As there is a need to replace conventional pesticides (organophosphates, carbamates, pyrethroids) with biorational pesticides, we evaluated the behavioural and toxicological responses of the German cockroach, Blattella germanica, exposed to the following monoterpenes, namely (+)-a-pinene, (-)-a-pinene, limonene, menthone, linalool, menthyl acetate and geraniol. Locomotor activity and repellency were quantified using a video tracking system. To study the effect on locomotor activity, larvae were exposed to filter papers treated with concentrations of monoterpenes ranging between 1.4 and 1,400 µg/cm2. Only menthyl acetate applied at a concentration of 14 µg/cm2 or higher increased the locomotor activity of the larvae. Repellency was evaluated by exposing larvae to circles of filter paper divided in two equal zones: one zone was treated with a solution of a monoterpene in acetone (14 or 140 µg/cm2) and the other with only acetone. Larvae were repelled by all the monoterpenes tested. The two concentrations of geraniol and the highest concentration of menthyl acetate and linalool were as repellent as DEET (positive control). The fumigant effect was evaluated by exposing larvae to vapour from 100 µl of pure monoterpene in a sealed container. The values of the 50% Knock-down Times (KT50), expressed in minutes, were: (+)-a-pinene: 11.8, (-)-a-pinene: 14.6, limonene: 81.0, menthone: 141.0, and linalool: 238.6. (+)-a-Pinene was as good a fumigant as dichlorvos (positive control, KT50 = 9.7 min). The least effective compounds were menthyl acetate and geraniol (both affected less than 50% of larvae after 490 min of exposure). In conclusion, (+)-a-pinene (for its fumigant effect), menthyl acetate (for its hyperactivant effect) and menthone and geraniol (for their repellent properties) could potentially be used for controlling B. germanica. |