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Results 781 to 810 of 2340:

Effect of nutritious and toxic prey on food preference of a predaceous ladybird, Coccinella septempunctata (Coleoptera: Coccinellidae)Original article

Mushtaq A. GUROO, Ahmad PERVEZ, Kuldeep SRIVASTAVA, Rakesh K. GUPTA

Eur. J. Entomol. 114: 400-406, 2017 | DOI: 10.14411/eje.2017.051

We investigated the predatory potential and food preference of different life stages of Coccinella septempunctata L. for a nutritious aphid (mustard aphid, Lipaphis erysimi) and toxic aphid (cabbage aphid, Brevicoryne brassicae). We provided all the life stages of C. septempunctata with either L. erysimi or B. brassicae and found that the second, third and fourth instar larvae and adult females of this predator consumed daily greater numbers of L. erysimi. However, the first instar larvae and adult males consumed similar numbers of both of these aphids. In choice condition, each larva, adult males and females were each provided separately with a mixed aphid diet in three proportions (i.e. low: high, equal: equal and high: low densities of L. erysimi: B. brassicae). We hypothesized that life stages of C. septempunctata will prefer L. erysimi regardless of its proportions. Laboratory experiments supported this hypothesis only at the adult level in terms of high values of β and C preference indices. However, it rejects this hypothesis at the larval level, as larvae preferred B. brassicae when provided with certain combinations and showed no preference in a few combinations. We infer that mixtures of nutritious and toxic aphids may enable this ladybird to overcome any probable nutritional deficiency and/or reduce the toxicity of a toxic diet, especially for the larvae. Results of the treatment in which a high proportion of B. brassicae were consumed along with fewer L. erysimi indicates that a mixed diet could be better for the development of immature stages of C. septempunctata.

New species of Cicadocoris (Hemiptera: Coleorrhyncha: Progonocimicidae) from mid-Jurassic deposits in northeastern ChinaOriginal article

Jia-Qian JIANG, Di-Ying HUANG

Eur. J. Entomol. 114: 355-364, 2017 | DOI: 10.14411/eje.2017.045

A new progonocimicid bug named Cicadocoris parvus sp. n. is described from the mid-Jurassic Haifanggou Formation at Daohugou, Ningcheng County, Inner Mongolia, northeastern China. It differs from other species by being distinctly smaller, veins dSc, R1 and Rs run parallel to one another and are nearly evenly spaced on left tegmen, widest length of apical half/basal half of left tegmen is 1.1 and that of right tegmen is 1.0. Thus, there are at least three species of Cicadocoris (Progonocimicidae) described from Daohugou. All these species are relatively abundant in the Haifanggou Formation and are remarkable representatives of the early Yanliao biota.

ERRATUM: Kukalová-Peck J. & Beutel R.G. 2012: Is the Carboniferous †Adiphlebia lacoana really the "oldest beetle"? Critical reassessment and description of a new Permian beetle family. Eur. J. Entomol. 109(4): 633-645.

J. KUKALOVA-PECK, R.G. BEUTEL

Eur. J. Entomol. 110 (1): 180, 2013 | DOI: 10.14411/eje.2013.027

Kukalová-Peck J. & Beutel R.G. 2012: Is the Carboniferous †Adiphlebia lacoana really the "oldest beetle"? Critical reassessment and description of a new Permian beetle family. Eur. J. Entomol. 109(4): 633-645. 

Legend to Fig. 6 in the above paper failed to state the source of the photograph used in Fig. 6A. The source was the same paper by Béthoux et al. (2010) as for Fig. 6B. We reprint below the corrected legend for Fig. 6.

Fig. 6. †Strephocladidae: †Homocladus grandis Carpenter, 1966, Late Carboniferous, Mazon Creek, Illinois. A - Fore wing, holotype, Fig. 1 from Béthoux et al. (2010) with lettering added. 1 - subcostal bulge; 2 - m brace formed by a cross-vein; 3 - flight-important mp-cua brace/fusion shared by Endoneoptera + Hemineoptera; 4 - claval line short, concave. B - †Homocladus cf. grandis, hind wing, Béthoux et al., 2010, Fig. 4. C - Same, venation and flexion lines verified by us with a photograph, fully homologized and identified by unified nomenclature as endoneopteran.

Is the Carboniferous †Adiphlebia lacoana really the "oldest beetle"? Critical reassessment and description of a new Permian beetle family

Jarmila KUKALOVÁ-PECK, Rolf G. BEUTEL

Eur. J. Entomol. 109 (4): 633-645, 2012 | DOI: 10.14411/eje.2012.075

Béthoux recently identified the species †Adiphlebia lacoana Scudder from the Carboniferous of Mazon Creek, Ill., USA as the oldest beetle. The fossils bear coriaceous tegmina with pseudo-veins allegedly aligned with "rows of cells" as they occur in Permian beetles and extant Archostemata. The examination of four new specimens of †Adiphlebia lacoana from the same locality revealed that the "cells" are in fact clumps of clay inside a delicate meshwork, and no derived features shared with Coleoptera or Coleopterida (= Coleoptera + Strepsiptera) were found. Instead, †Adiphlebia lacoana bears veinal fusions and braces similar to extant Neuroptera. These features support a placement in †Strephocladidae, and are also similar to conditions found in †Tococladidae. These unplaced basal holometabolan families were erroneously re-analyzed as ancestral Mantodea and Orthoptera. Homologization of the wing pairs in neopteran lineages is updated and identification errors are corrected. A new Permian beetle family †Moravocoleidae [†Protocoleoptera (= Permian Coleoptera with pointed unpaired ovipositor; e.g., †Tshekardocoleidae)] is described.

An Erratum has been published for this article: https://doi.org/10.14411/eje.2013.027

Adult demography, spatial distribution and movements of Zerynthia polyxena (Lepidoptera: Papilionidae) in a dense network of permanent habitats

Tatjana ÈELIK

Eur. J. Entomol. 109 (2): 217-227, 2012 | DOI: 10.14411/eje.2012.028

The adult demographic parameters, mobility, nectar choice and how the spatial distribution of males and females of Z. polyxena is affected by the distribution and abundance of host-plants, and adults of the opposite sex was studied in a population of this species inhabiting a dense network of permanent habitats (totalling 8.7 ha). The population size was estimated to be ca. 300 individuals. The average adult lifespan was 4.4 days and the maximum 23 (male) and 20 (female) days. The capture probability was higher for males than females due to the more conspicuous behaviour and bounded area of activity of males. A slow increase was followed by a slow decrease in the sex specific parabolic recruitment curve, indicating slight protandry and long emergence period, probably due to habitat heterogeneity. The spatial distribution of host plants (Aristolochia lutea) is the key factor determining the spatial distribution of adults. There was a strong positive correlation between male and female density at each patch, both of which were dependent on the cover of host plants growing in sunny conditions. In searching for A. lutea plants suitable for oviposition, females fly greater distances and move more frequently between patches than males. The size, shape and orientation of the male home range were influenced by the size, shape and orientation of stands of host-plants in sunny positions, but not by patch area. Such adult fidelity to stands of host-plants in sunny positions indicates that the spatial distributions of oviposition sites, mate-locating sites and larval habitats of Z. polyxena overlap. The better statistical fit and much lower probabilities for long-distance movements generated by a negative exponential function than an inverse power function are probably due to the small size and high habitat connectivity of the site studied. Adults were opportunistic in their use of nectar plants. Traditional management is the key factor for maintaining permanent habitats for this species in a grassland biotope.

Antibacterial activity of lysozyme in the desert locust, Schistocerca gregaria (Orthoptera: Acrididae)

Amr A. MOHAMED, Mohamed ELMOGY, Moataza A. DORRAH, Hesham A. YOUSEF, Taha T.M. BASSAL

Eur. J. Entomol. 110 (4): 559-565, 2013 | DOI: 10.14411/eje.2013.076

The ability of biocontrol agents to overcome the immune defense of pests is a crucial issue. This is the first study of lysozyme activity as an inducible humoral component of the defense of Schistocerca gregaria, which depends on the recognition of the elicitor molecules of pathogens and not on epidermal wounding or a spiking effect. The level of lysozyme activity in fat body, haemocytes and haemolymph plasma of naïve and immunologically challenged 5th instar S. gregaria was evaluated using the zone of inhibition test against Micrococcus lysodeikticus. Various Gram-positive and Gram-negative bacteria as well as peptidoglycans (PGN) and lipopolysacchrides (LPS) of bacterial cell walls induce and increase in the level of lysozyme activity. Escherichia coli induced an increase in the level of activity of lysozyme in the fat body, haemocytes and plasma, but not in mid gut epithelium, 6-12 h after an immunological challenge and then it decreased to the constitutive level after 72 h. This study revealed that in S. gregaria there is a constitutive and a bacteria-inducible level of lysozyme activity, which protects it against infection by both Gram-negative and Gram-positive bacteria.

Morphological variation and sex-biased frequency of wing dimorphism in the pygmy grasshopper Tetrix subulata (Orthoptera: Tetrigidae)

Anja STEENMAN, Arne W. LEHMANN, Gerlind U.C. LEHMANN

Eur. J. Entomol. 110 (3): 535-540, 2013 | DOI: 10.14411/eje.2013.071

Dimorphism in wing length is well known in many insect species. It is generally believed that a trade-off between dispersal and reproduction exists, with the long-winged (LW) morph being a better disperser due to its superior flight capability. The short-winged (SW) morph is less mobile and it is hypothesised that females of this morph invest more of their energy reserves in producing offspring. We determined the variation in body and wing size in the pygmy grasshopper Tetrix subulata (Orthoptera: Tetrigidae). The results of the morphological study support the occurrence of two clearly distinct wing morphs in both sexes. SW individuals, especially males, were smaller and in accord with proposed developmental instability showed greater variability in body size than LW individuals. Using data for 700 wild-caught individuals from 10 populations, we demonstrate a variable frequency in the percentage of LW individuals, ranging from all-LW to all-SW populations, even if the LW morph is by far the most common morph in an area. The male-biased percentage of LW individuals recorded in intermediate populations supports a difference in the dispersal reproduction trade-off between the sexes.

Expression of cytochrome P450 CYP6B6 in the different developmental stages of the insect Helicoverpa armigera (Lepidoptera: Noctuidae)

Xuetao ZHANG, Dan YUAN, Li DING, Pan LI, Fen LI, Xiaoning LIU

Eur. J. Entomol. 110 (1): 39-45, 2013 | DOI: 10.14411/eje.2013.005

In order to determine when during the development of H. armigera CYP6B6 is expressed, we measured the width of the head capsule, the length of the body and weight of the different life stages of the cotton bollworm reared under laboratory condition. The larvae took about 20 d to complete their development under these conditions, the pre-pupae about 4 d, pupae about 9 d, and the adults lived for about 9 d and the eggs took about 4 d to hatch. Knowing this it was possible to determine the pattern of cytochrome P450 CYP6B6 expression at different stages in the life cycle of H. armigera using real-time quantitative polymerase chain reaction (RT-qPCR). The CYP6B6 gene was expressed in all the developmental stages of the cotton bollworm. The results indicate that the level of expression was lower in the egg, pre-pupal, pupal and adult stages than in larvae. The level of expression of CYP6B6 decreased from the 1st to the 3rd instar larva, with the lowest level recorded in the 3rd instar larvae and then increased reaching its highest value in 6th instar larvae. A similar trend in the expression of CYP6B6 was detected using immunohistochemistry. As the results show, more efficient control of the cotton bollworm can be achieved if insecticides are applied when the larvae of H. armiger are in the 3rd instar, because at that stage the eat little food and there is a low level of detoxifying enzymes in the larvae.

Polyphagous predatory rove beetles (Coleoptera: Staphylinidae) induce winged morphs in the pea aphid Acyrthosiphon pisum (Hemiptera: Aphididae)

Adalbert BALOG, Mohsen MEHRPARVAR, Wolfgang W. WEISSER

Eur. J. Entomol. 110 (1): 153-157, 2013 | DOI: 10.14411/eje.2013.021

A number of aphid species have been shown to produce winged dispersal morphs in the presence of natural enemies. Previous studies tested specialized aphid predators such as ladybirds or lacewing larvae. We confronted colonies of pea aphids with the polyphagous rove beetles, Drusilla canaliculata and Tachyporus hypnorum. For both predators we found that the percentage of winged morphs increased in predator-attacked pea aphid colonies compared to a control. The behaviour of the two rove beetles species was noticeably different. D. canaliculata mostly foraged on the ground and rarely on the plant, while T. hypnorum was almost exclusively observed on the plants, causing a higher number of aphids to drop to the ground, which resulted in a stronger increase in winged morph production. Our results clearly show that not only monophagous aphid predators but also more polyphagous insect predators, which include aphids in their diet, can induce aphids to produce winged morphs.

Dispersal of Aphytis melinus (Hymenoptera: Aphelinidae) after augmentative releases in citrus orchards

Lucia ZAPPALÀ, Orlando CAMPOLO, Saverio Bruno GRANDE, Francesco SARACENO, Antonio BIONDI, Gaetano SISCARO, Vincenzo PALMERI

Eur. J. Entomol. 109 (4): 561-568, 2012 | DOI: 10.14411/eje.2012.070

The efficacy of natural enemies in controlling pests under field conditions is largely correlated with their capacity to spread within infested crops. In this study the spatial dispersal of the California red scale parasitoid Aphytis melinus DeBach (Hymenoptera: Aphelinidae) was evaluated in the field after augmentative releases. The experiment was conducted in 2007 in six 1-ha plots in a Sicilian citrus orchard under integrated pest management. A total of 180,000 A. melinus adults was released in each of three plots and the other plots were left as untreated control. The flight range of the parasitoid was evaluated, for 35 days after the release, on 16 trees per each plot, located at 20 and 40 m from the central release point using yellow sticky traps activated with Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae) sexual pheromone and by monitoring the percentage parasitism of the scale on fruits and twigs. The effects of the distance from the release point and density of susceptible stages of host on parasitoid dispersal were evaluated. The number of wasps captured during the whole trial was greater in the traps located 20 m from the release point than in those at 40 m and in the control plots. Aphytis melinus dispersed over distances less than 40 m based on both the lower percentage parasitism and numbers captured recorded at distances of 40 m. The results are discussed in the context of the biological control of California red scale in citrus orchards by means of wasp releases. In particular, the release points should be no more than 40 m apart for a quick and homogeneous colonization of the area treated.

Analysis of tissue dependent DNA yield for optimal sampling of micro-moths in large-scale biodiversity surveys

Carlos LOPEZ-VAAMONDE, Floris C. BREMAN, David C. LEES, Jeroen VAN HOUDT, Jurate DE PRINS

Eur. J. Entomol. 109 (1): 1-6, 2012 | DOI: 10.14411/eje.2012.001

DNA barcoding surveys of small insects usually extract DNA from either a complete insect or a leg. Little is known about how to optimize DNA quantity and quality from different insect parts while preserving a morphological voucher. Here, we quantify DNA yield from different body parts (antenna, hind leg, forewing, hind wing and abdomen) of the micro-moth Cameraria ohridella (Lepidoptera: Gracillariidae) using fluorescent nucleic acid stain (PicoGreen). Samples were preserved in 100% ethanol or dried for three weeks. Our experiment was designed to encompass practical sampling options during fieldwork. DNA quality was assessed by PCR amplification of the mitochondrial COI barcode fragment. In addition, we compared PCR amplification using Platinum® Taq and Qiagen DNA Polymerase and quantified sequence success of amplified DNA. We show that overall, dry parts showed higher eluted DNA yields. PCR and sequencing success rate were slightly higher for dry tissue than ethanol-preserved parts. We also show that Platinum® Taq yielded the highest PCR success rate and that all dry tissues are sequenceable. The optimal strategy for DNA barcoding surveys is therefore to mount micro-Lepidoptera specimens in the field for morphological analysis and sample tissues (hind legs are favoured) from dried samples at a later time (several weeks) in the lab for DNA barcoding using preferentially Platinum® Taq. If larger amounts of DNA are required (i.e. for nuclear gene sequencing), several legs from one side of the specimen or the abdomen should be preserved in pure ethanol.

Genus-group names of Afrotropical flea beetles (Coleoptera: Chrysomelidae: Alticinae): Annotated catalogue and biogeographical notes

Maurizio BIONDI, Paola D'ALESSANDRO

Eur. J. Entomol. 107 (3): 401-424, 2010 | DOI: 10.14411/eje.2010.049

This paper consists of an up to date annotated catalogue of the Afrotropical genera of Alticinae (Chrysomelidae), with biogeographical notes on the flea beetle fauna occurring in Sub-Saharan Africa and Madagascar. The following new synonymies are proposed: Eugonotes Jacoby, 1897 (a subgenus of Sanckia Duvivier, 1891) = Brancucciella Medvedev, 1995 syn. n.; Amphimela Chapuis, 1875 = Dibolosoma Jacoby, 1897 syn. n.; Amphimela Chapuis, 1875 = Halticova Fairmaire, 1898 syn. n.; Podagrica Chevrolat, 1837 = Podagrixena Bechyné, 1968 syn. n.; Aphthona Chevrolat, 1837 = Pseudeugonotes Jacoby, 1899 syn. n.; Nisotra Baly, 1864 = Pseudonisotra Bechyné, 1968 syn. n. The following new combinations are proposed: Afrorestia sjostedti (Weise, 1910) comb. n. (from Crepidodera); Bechuana natalensis (Jacoby, 1906) comb. n. (from Ochrosis); Sesquiphaera natalensis (Jacoby, 1906) comb. n. (from Sphaeroderma). The genus Hildenbrandtina Weise, 1910 is trasferred from Galerucinae to Alticinae. New distributional data for many genera in the Afrotropical region is provided.

The role of plant phenology in the host specificity of Gephyraulus raphanistri (Diptera: Cecidomyiidae) associated with Raphanus spp. (Brassicaceae)

Janine VITOU, Marcela SKUHRAVÁ, Václav SKUHRAVÝ, John K. SCOTT, Andy W. SHEPPARD

Eur. J. Entomol. 105 (1): 113-119, 2008 | DOI: 10.14411/eje.2008.016

Recent host records for Gephyraulus raphanistri (Kieffer), a flower-gall midge, show restriction to Raphanus raphanistrum throughout Europe. Gephyraulus raphanistri has never been reported infesting commercially grown Brassica crops. Historical records showing a broad host range appear to have resulted from confusion with new or as yet undescribed Gephyraulus spp. and Contarinia nasturtii (Kieffer), a known gall-former of Brassica and other related genera. This study tested host specificity of G. raphanistri in the field in Europe by manipulating host plant phenology of actual and potential hosts in the genera Raphanus and Brassica as part of a risk assessment of the insect as a potential biological control agent of R. raphanistrum, one of the most important weeds of crops in Australia. Raphanus raphanistrum raphanistrum (wild radish), R. raphanistrum landra (coastal wild radish), Raphanus sativus (radish) and Brassica napus (oilseed rape cultivar) were phenologically synchronised for initial flowering and planted out in a flowering time and species block design near a natural population of R. r. landra hosting a natural population of G. raphanistri. Three generation peaks in gall formation were observed in the experiment, with galls developing on all test plants with an apparent preference for R. r. landra. The high field specificity of this gall midge is driven by the synchrony of oviposition and flower availability, not host physiological incompatibility or behavioural unacceptability. Commercially grown Brassica spp. are not suitable hosts for G. raphanistri because in the field they differ in flowering phenology from Raphanus raphanistrum. The overlap in the flowering phenology of the crop and weed in Australia makes this insect unsuitable as a biological control agent.

Differential accumulation of energy by the colour morphs of the pea aphid Acyrthosiphon pisum (Hemiptera: Aphididae) mirrors their ecological adaptations

Seyed Mohammad AHSAEI, Seyed Mohammad TABADKANI, Vahid HOSSEININAVEH, Hossein ALLAHYARI, Mahdieh BIGHAM

Eur. J. Entomol. 110 (2): 241-245, 2013 | DOI: 10.14411/eje.2013.035

The pea aphid, Acyrthosiphon pisum (Hemiptera: Aphididae), is a well-studied species in terms of its colour polymorphism, where it occurs as two distinct colour morphs, red and green. It is proposed that the occurrence and maintenance of this polymorphism is an adaptive response to environmental factors, in particular natural enemies and host plant quality. We hypothesized that these adaptations are directly mirrored in the energy reserves accumulated by the different colour morphs during their pre-adult stages and reflect their specialization for particular ecological roles. We quantitatively measured the different energy reserves of red and green pea aphids and found that the total energy reserves of these morphs did not differ. Interestingly, these reserves were made up of different components in the red and green colour morphs. There was a higher percentage content of water-soluble carbohydrates and lipids in the red clones and higher percentage content of protein in green clones. These finding are in accordance with green clones being more fecund than red ones and needing more protein for reproduction than red clones, which produce more winged offspring when crowded or in response to the presence of natural enemies and so, need more lipids and carbohydrates to fuel their walking and flight. Apparently, different colour morphs are physiologically specialized to adjust their energy reserves in relation to their specific ecological adaptations and maximize their fitness in terms of dispersal, reproduction, defense and survival.

Does monogeny enable gall midges (Diptera: Cecidomyiidae) to regulate their sex ratio?

Seyed Mohammad TABADKANI, Ahmad ASHOURI, Farhad FARHOUDI

Eur. J. Entomol. 109 (3): 339-343, 2012

Monogeny, the production of unisexual broods by individual females, is widely recorded in gall midges (Diptera: Cecidomyiidae). Theoretical models propose that the adjustment of offspring sex ratio by females may pre-dispose the evolution of monogeny in gall midges however empirical studies in this field are superficial. Expressed more simply, monogeny may enable individual female gall midges to decrease or increase the number of male and female progeny they produce in response to changes in environmental conditions. Host quality/size is repeatedly reported to influence sexual investment in insects in terms of sex ratio adjustment. In this paper, we examined the sex ratio of the offspring of the monogenous predatory gall midge Aphidoletes aphidimyza attacking low and high abundances of the cotton aphid, Aphis gossypii. Two consecutive generations of female gall midges were presented with either a low or high abundance of aphids in each generation and the sex ratio of their progenies determined. There was no difference between the sex ratio of the progenies that developed on the high or low abundance of A. gossypii in the two generations. Apparently, the females did not regulate the number of female and male progenies, or adjust the numbers of male or female's eggs they produced in response to the changes in the abundance of prey. Results of this study do not support the theory of sex ratio regulation proposed for monogenous gall midges. It is likely that the skewed sex ratio in most species of monogenous gall midges is a consequence of differential mortality of male and female progenies under harsh conditions. The finding that male and female larvae did not differ in the number of aphids they require to complete their development supports this claim.

Pre- and post-parturial aspects of scorpion reproduction: a review

Michael R. WARBURG

Eur. J. Entomol. 109 (2): 139-146, 2012 | DOI: 10.14411/eje.2012.018

Although scorpions are an ancient group their method of reproduction is rather complex and poorly studied. This review aims at clarifying some of the aspects of their reproduction that are important for understanding the reproductive ecology of other arthropods, including insects. The following aspects of scorpion reproduction are discussed and reviewed: mating, insemination, fertilization, gestation, parturition and birth. The onset of gestation and its duration are difficult to determine as both depend on the time of fertilization, for which there are no accurate estimates. There are only a few records of the time between birth and emergence of a larva from the maternal envelope in apoikogenic scorpions, which is important for a better understanding of ovoviviparity. All these questions are important as the answers will greatly enhance our understanding of the population ecology of scorpions in terms of the recruitment rates of cohorts and their chances of survival.

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

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

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

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

Effect of temperature and species of plant on the consumption of leaves by three species of Orthoptera under laboratory conditions

Spyridon A. ANTONATOS, Nikolaos G. EMMANUEL, Argyro A. FANTINOU

Eur. J. Entomol. 110 (4): 605-610, 2013 | DOI: 10.14411/eje.2013.082

In the Mediterranean area the orthopterans Calliptamus barbarus barbarus, Dociostaurus maroccanus and Tettigonia viridissima are considered to be pests of major economic importance crop plants. The aim of the present study was to evaluate the area of leaf of vine, cotton and potato plants consumed by these Orthoptera at two temperatures. Leaf area was determined for each plant species before the leaves were provided to the insects. Virgin male and female adults were allowed to feed on a leaf of each plant species and the area of leaf consumed was determined after 24h at 25 and 30°C. Results showed that temperature had a significant affect on consumption by both males and females of all the species examined, and it was higher at 30°C. The influence of plant species was not significant for C. barbarus barbarus. D. maroccanus and T. viridissima, however, consumed a greater area of potato leaves than of the other species of plants. Females consumed more food than males in all the species tested. The results of the present study provide a first approximation of the area of leaf consumed and the potential loss of foliage these plants might suffer if attacked by the three species of Orthoptera tested.

Characterization of ten polymorphic microsatellite markers for an endangered butterfly Argynnis niobe and their cross-species utility in the closely related species A. adippe (Lepidoptera: Nymphalidae)

Jan ZIMA Jr., Dan LE©TINA, Martin KONVIÈKA

Eur. J. Entomol. 110 (2): 383-387, 2013 | DOI: 10.14411/eje.2013.098

The Niobe Fritillary, Argynnis niobe, is a habitat specialist and as a consequence is highly endangered in contemporary Europe. To investigate its genetic diversity and population structure, 10 polymorphic microsatellite loci were developed and characterized, using a recently developed pyrosequencing method. The number of alleles per locus ranged from 2 to 21, and the observed and expected heterozygosities varied from 0.17 to 0.53 and from 0.24 to 0.92, respectively. These loci were also successfully used to study the genetic diversity of a closely related species, the High Brown Fritillary, Argynnis adippe, and will be used in future population structure studies of both these species.

The aphidophagous predator Harmonia axyridis (Coleoptera: Coccinellidae) in Greece, 1994-1999

Dimitrios C. KONTODIMAS, George J. STATHAS, Aggeliki F. MARTINOU

Eur. J. Entomol. 105 (3): 541-544, 2008 | DOI: 10.14411/eje.2008.072

During the years 1994-1999, several hundreds of thousands of H. axyridis adults were released at various cultivations infested by aphids (citrus, vegetable and bean crops, maize etc.) and on ornamental plants in urban settings in central and southern Greece (mainly Attica and Peloponessos region) as well as on several islands. Between 1995-1999, spring sampling was conducted in some areas, just prior to releases, in order to determine if H. axyridis overwintered in the field. No presence of H. axyridis was recorded in any of the orchards where the predator had been released save in spring of 1998 and 1999 when small colonies (<50 individuals) of overwintered H. axyridis adults were observed in the Attica region. The above results suggest an inability of released H. axyridis populations to establish in Greece, although in some areas this species became an important biocontrol agent during the growing season.

The compound eye of Orgyia antiqua (Lepidoptera: Lymantriidae): Sexual dimorphism and light/dark adaptational changes

Ting Fan (Stanley) LAU, Victor Benno MEYER-ROCHOW

Eur. J. Entomol. 104 (2): 247-258, 2007 | DOI: 10.14411/eje.2007.039

Structure and photomechanical changes upon light/dark adaptation in the superposition compound eyes of the highly sexually dimorphic Orygia antiqua were studied by light and electron microscopy. The eyes of the fully winged male differ from those of the wingless, sedentary female in several respects: they are significantly larger, display a more regular ommatidial array, have a wider clearzone and possess a much more substantial tracheal tapetum. However, the eyes of the female exhibit more pronounced photomechanical changes upon light/dark adaptation than those of the male. We believe that for females, on account of their limited mobility, it is necessary that their eyes can cope with widely fluctuating brightnesses, but that visual sensitivity and resolving power are less important to them than to the actively flying males. Although the latter may be attracted to the females by pheromones, males in their diurnal searches will have to visually avoid obstacles and predators. Moreover, because of their ability to fly, males can seek shelters or shaded areas and unlike the sedentary females avoid prolonged exposures to potentially hazardous light levels. This could explain why the eyes of the females exhibit more pronounced photomechanical responses to changes in ambient light levels.

Ecology and life histories of two Alpine-Apenninic species of Velia (Hemiptera: Heteroptera: Veliidae)

Fabio CIANFERONI, Giacomo SANTINI

Eur. J. Entomol. 109 (3): 427-434, 2012

Velia currens (Fabricius, 1794) and V. gridellii Tamanini, 1947 are two South European species of Veliidae, whose ecology and behaviour are poorly known. The aims of this study were to investigate their life histories, quantify occurrence of wing polymorphism and gather information on their degree of co-occurrence. Nine different populations were regularly surveyed from April to November 2010. Furthermore, a dataset containing information on the occurrence of the two species and the presence of winged morphs at 294 sites was compiled from museum collections, private collections and published literature. No evidence for multivoltinism was detected in either species. However, oviposition and and/or hatching were protracted in time so that early-instar nymphs and adults co-occurred up to midsummer. Although their distributional ranges completely overlap at a large spatial scale, the two species co-occurred only rarely at the same sites and the degree of co-occurrence was lower than expected by chance. Winged specimens were rarely recorded. At least in V. gridellii, the numbers of winged individuals were inversely related to the altitudes of the sites. During the summer, when some of the streams surveyed dried up, several specimens were found in an apparent state of lethargy, under stones. It is hypothesized that the ability to aestivate, coupled with the ability to walk from one site to another may reduce the advantage associated with producing winged forms and account for the low rate of occurrence of macropterism in these species.

First record of the harlequin ladybird, Harmonia axyridis (Coleoptera: Coccinellidae) in the Caucasus

Natalia A. BELYAKOVA, Sergey Ya. REZNIK

Eur. J. Entomol. 110 (4): 699-702, 2013 | DOI: 10.14411/eje.2013.093

This is the first record of the harlequin ladybird Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) occurring in the Caucasus (Sochi region of Krasnodar territory, Russia). All the adults collected in the field there and reared from collected eggs, larvae and pupae, and their progeny were H. axyridis f. succinea, which is the most common morph in natural populations in South-Eastern Asia and the Russian Far East as well as in invasive populations in the Americas and Europe. In contrast in Western Siberia f. axyridis predominates and this indicates that an occasional introduction from the closest native range in Siberia cannot be considered as the source of the Caucasian population. It is known that populations of H. axyridis can also differ in their photoperiodic responses. The results of earlier experiments on H. axyridis, which originated from the Russian Far East, indicate that the threshold day lengths for the acceleration of preimaginal development and deceleration of reproductive maturation were 13-14 h, while for the invasive populations of this species in Europe these two thresholds are approximately 12 h. In the population studied, the thresholds for both of these photoperiodic responses were also approximately 12 h. Thus, it is concluded that the population of H. axyridis studied is a further eastward continuation of the invasion of this species in Europe.

Isolation and characterization of microsatellite loci for the mud-dauber wasp Trypoxylon (Trypargilum) albitarse (Hymenoptera: Crabronidae)

Juliano DA COSTA ALMEIDA, Antonio Carlos BRAGATO BERGAMASCHI, Alexandra SANCHES, Terumi HATANAKA, Marco Antonio DEL LAMA

Eur. J. Entomol. 110 (3): 541-543, 2013 | DOI: 10.14411/eje.2013.072

This paper describes the characterization of a set of nine microsatellite markers for the pipe-organ mud-dauber wasp, Trypoxylon albitarse F. (Hymenoptera: Crabronidae), a common solitary wasp species in Brazil. Eight of the nine loci described were found to be polymorphic. The number of alleles ranged from three to 11. Observed and expected heterozygosity on the population level ranged from 0.135 to 0.891 and 0.177 to 0.865, respectively. Genotypic analyses revealed no deviations from Hardy-Weinberg equilibrium or linkage disequilibrium after sequential Bonferroni correction. Cross-species amplification was also tested for nine related species and positive amplifications were found in most of the assays. These markers will be useful in studies involving relatedness analysis and investigations of the population genetics of these wasps.

Male mandible trimorphism in the stag beetle Dorcus rectus (Coleoptera: Lucanidae)

Yutaka IGUCHI

Eur. J. Entomol. 110 (1): 159-163, 2013 | DOI: 10.14411/eje.2013.022

Males in many beetles show horn or mandible dimorphism. The stag beetle Dorcus rectus was assumed to have dimorphic males, but in this species there are not two but three visually distinct mandibular phenotypes. The aim of this study is to determine if the three phenotypes represent an allometric trimorphism in this species by studying the scaling relationship between body length and mandible length in 148 adult males and 31 adult females. The relationship was fitted using the following four statistical models; a simple line, a logistic curve, a continuous segmented line and a discontinuous line. The best-fitting model for the males was a discontinuous line with two break points and that for the females a simple line. The male data was also well fitted by a logistic curve. The discontinuous linear model divided the males into three groups that were in good agreement with the three phenotypes. These results suggest that a subtle allometric trimorphism possibly exists in males of this species. Small males of this species have no distinct teeth on their mandibles, whereas small males of D. striatipennis and D. curvidens, which are closely related to D. rectus, have a pair of distinct teeth on their mandibles. The phylogenetic relationship of these Dorcus species suggests that the trimorphism in D. rectus may have arisen through the loss of teeth in small males.

An improved lure for trapping the bark beetle Dendroctonus armandi (Coleoptera: Scolytinae)

Shou-An XIE, Shu-Jie LV

Eur. J. Entomol. 109 (4): 569-577, 2012 | DOI: 10.14411/eje.2012.071

The pine bark beetle, Dendroctonus armandi, is a native pest restricted to forests in the Qinling Mountains in China. There was an outbreak of this species there that affected over 0.36 million hectares of pine forest. We hypothesized that there are differences between the numbers of beetles captured by traps baited with various combinations of candidate semiochemicals extracted from the hindguts of D. armandi. In order to determine whether a better operational lure could be developed for D. armandi, we analyzed the volatiles in extracts of the hindgut of D. armandi and tested various combinations of candidate semiochemicals. The GC-MS and GC-FID analyses of volatiles in the extracts of the hindguts of D. armandi collected at different stages of the attack revealed that they are mainly a-pinene, b-caryophyllene and (+)-3-carene with minor amounts of myrcene, limonene, verbenol and verbenone. We tested various combinations of these candidate semiochemicals in order to determine an optimal blend. Our results suggest that the addition of b-caryophyllene to either a-pinene, or blends of a-pinene and other candidate semiochemicals, significantly enhanced the attractiveness of the lures for D. armandi. Field trapping experiments indicated that the blends that included b-caryophyllene, myrcene and other candidate semiochemicals resulted in significantly higher trap catches (161-243% higher) than a-pinene alone. Therefore, a simple lure consisting of a-pinene and b-caryophyllene would be an optimal blend for D. armandi. We conclude that this blend of semiochemicals may provide a better method of reducing the numbers of D. armandi in forest ecosystem.

Proteomic approach to understanding the maternal effect in the flesh fly, Sarcophaga bullata (Diptera: Sarcophagidae)

Aiqing LI, Liangliang WANG, Min LIANG, Qiugen ZHOU, Guobao WANG, Fanfan HOU

Eur. J. Entomol. 109 (1): 7-14, 2012 | DOI: 10.14411/eje.2012.002

Progeny of the flesh fly Sarcophaga bullata exposed to short day length show a maternal effect that prevents the expression of pupal diapause. Although ecological aspects of this effect are well studied, not enough is known about the molecular mechanisms underlying this maternal effect. In this study, two-dimensional electrophoresis was performed to detect differences of the abundance of certain proteins in the ovaries of this fly kept under long day and short day conditions for 2 days after eclosion. Eleven proteins that were abundant and showed significant changes were selected for mass spectrometric identification. Ovary proteins that increased in abundance under short-day conditions were similar to twinstar CG4254-PA, muscle protein 20-like protein, GA13413-PA, gene analogous to small peritrophins (Gasp CG10287-PA) and Ribosomal protein LP1 CG4087-PA. Ovary proteins that decreased in abundance under short-day conditions were similar to the ATP synthase beta subunit, fk506-binding protein and storage protein-binding protein. The 2-D proteome maps included 2 additional unknown proteins that were more abundant and 1 that was less abundant in the ovaries of 2-day old short-day females. Twinstar CG4254-PA, muscle protein 20-like protein and GA13413-PA harbour an actin-binding domain. That the 3 actin-binding proteins increase in abundance suggests that it is likely that an alteration in the actin cytoskeleton is involved in this maternal effect in the flesh fly.

Patterns in diurnal co-occurrence in an assemblage of hoverflies (Diptera: Syrphidae)

Manuela D'AMEN, Daniele BIRTELE, Livia ZAPPONI, Sönke HARDERSEN

Eur. J. Entomol. 110 (4): 649-656, 2013 | DOI: 10.14411/eje.2013.088

In this study we analyzed the inter-specific relationships in assemblages of syrphids at a site in northern Italy in order to determine whether there are patterns in diurnal co-occurrence. We adopted a null model approach and calculated two co-occurrence metrics, the C-score and variance ratio (V-ratio), both for the total catch and of the morning (8:00-13:00) and afternoon (13:00-18:00) catches separately, and for males and females. We recorded discordant species richness, abundance and co-occurrence patterns in the samples collected. Higher species richness and abundance were recorded in the morning, when the assemblage had an aggregated structure, which agrees with previous findings on communities of invertebrate primary consumers. A segregated pattern of co-occurrence was recorded in the afternoon, when fewer species and individuals were collected. The pattern recorded is likely to be caused by a number of factors, such as a greater availability of food in the morning, prevalence of hot and dry conditions in the early afternoon, which are unfavourable for hoverflies, and possibly competition with other pollinators. Our results indicate that restricting community studies to a particular time of day will result in certain species and/or species interactions not being recorded.

The usefulness of chromosomes of parasitic wasps of the subfamily Eupelminae (Hymenoptera: Chalcidoidea: Eupelmidae) for subfamily systematics

Lucian FUSU

Eur. J. Entomol. 105 (5): 823-828, 2008 | DOI: 10.14411/eje.2008.109

Karyotypes of 16 Eupelminae species were analyzed. The haploid chromosome number was found to be much more diverse than the n = 5 previously recorded for three studied species. All species investigated of Eupelmus (Eupelmus), Eupelmus (Macroneura), Merostenus excavatus and three species of Anastatus have a karyotype of n = 5; n = 7 in Eupelmus (Episolindelia) linearis, n = 8 in Arachnophaga picardi, and n = 10 in Anastatus ruficaudus. The modal chromosome number is n = 5 and this is considered to be the plesiomorphic character state for the subfamily; karyotypes with higher chromosome numbers are hypothesized to be derived independently from the ancestral state by centric fission. This cytogenetical data provides important information on the subfamily systematics, especially the subgeneric classification of Eupelmus and generic placement of Eupelmus rostratus.

Inhabiting warm microhabitats and risk-spreading as strategies for survival of a phytophagous insect living in common pastures in the Pyrenees

Gregor STUHLDREHER, Luis VILLAR, Thomas FARTMANN

Eur. J. Entomol. 109 (4): 527-534, 2012 | DOI: 10.14411/eje.2012.066

The breakdown of the transhumant grazing system in the Spanish Pyrenees has led to a severe decline in the area of pastures. However, in the high mountain zone there are still large areas of species-rich grasslands. The aim of this study was to assess the oviposition preferences of the shrub-feeding Blue-spot hairstreak, Satyrium spini (Denis & Schiffermüller, 1775), in montane common pastures in the Spanish Pyrenees and recommend a way of managing these grasslands that favours this species. Our study showed that females of S.spini laid their eggs on Dwarf buckthorn (Rhamnus pumila Turra) and Alpine buckthorn (R. alpina L.), which are novel host plant records for Spain. A warm microclimate was of crucial importance for egg-laying. Occupied plants grew mostly at sparsely vegetated grassland sites where there were large patches of bare rocks, stones or gravel. Most egg batches were laid close to the ground and 75% consisted of only one egg. The number of batches per R. pumila plant was higher on east-, south- and west-facing slopes than on north-facing slopes. Presence of eggs and the number of egg batches per R. pumila plant were best explained by a long sunshine duration. At high altitudes particularly warm microhabitats seem to be more important for S.spini than at lower altitudes in Central Europe. We assume that the preference for unusually warm microhabitats is explained by the cold climatic conditions near the altitudinal range limit of the species. That most of the eggs were laid singly and not in small batches as in Central Europe might be a risk-spreading strategy to cope with the harsh climatic conditions and the high inter-annual variation in weather conditions in the high mountain zone in the Pyrenees. The best way to maintain open grasslands for S. spini and other thermophilous grassland species in the high mountain zone of the Pyrenees is to use the traditional combination of sheep and cattle grazing.

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