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BOOK REVIEW: Wajnberg E., Bernstein C. & van Alphen J.: Behavioral Ecology of Insect Parasitoids. From Theoretical Approaches to Field Applications.I. HODEKEur. J. Entomol. 105 (3): 512, 2008 | DOI: 10.14411/eje.2008.067 Blackwell, Malden, MA & Oxford, 2008, 445 pp., ISBN 978- 1-4051-6347-7. Price EUR 60.80, GBP 45.00. |
Female copulatory tubes and the subdivision of the genus Anthocoris (Heteroptera: Anthocoridae: Anthocorini)Yunling KE, Wenjun BUEur. J. Entomol. 104 (1): 89-98, 2007 | DOI: 10.14411/eje.2007.014 We report a systematic study of the female copulatory tubes of forty species in the genus Anthocoris, most of which are from the Northern Hemisphere. Our results indicate that female copulatory tubes can be used as a reliable character to identify females and analyze phylogenetic relationships in this genus. We propose thirteen species groups based on the copulatory tubes of females, other morphological characters of both sexes, and the previous species groups adopted in the continental faunas. |
Comparative behavioral and EAG responses of female obliquebanded and redbanded leafroller moths (Lepidoptera: Tortricidae) to their sex pheromone componentsAyhan GÖKÇE, Lukasz L. STELINSKI, Larry J. GUT, Mark E. WHALONEur. J. Entomol. 104 (2): 187-194, 2007 | DOI: 10.14411/eje.2007.029 Studies were conducted investigating the responses of female obliquebanded leafrollers, Choristoneura rosaceana (Harris) and redbanded leafrollers, Argyrotaenia velutinana (Walker) (Lepidoptera: Tortricidae), to components of their sex pheromone. Electroantennogram (EAG) recordings revealed significant responses from antennae of female moths of both species to the major pheromone component, (Z)-11-tetradecenyl acetate, at dosages ranging from 2 µg - 2 mg. However, tested individually, the minor pheromone components of the obliquebanded leafroller, (E)-11-tetradecenyl acetate and (Z)-11-tetradecenol, elicited little or no antennal response from conspecific females. This result was consistent for redbanded leafroller females, which showed only weak responses to the minor component (E)-11-tetradecenyl acetate at a 2 mg dosage. For both species, species-specific blend ratios of the Z and E isomers of tetradecenyl acetate did not elicit a greater antennal response than the Z isomer alone. Virgin females of each species (2-4 d old) were placed into 1-liter plastic assay chambers with constant throughput of carbon-filtered air passed through 1-liter flasks containing rubber septa loaded with (Z)- and (E)-11-tetradecenyl acetates and (Z)-11-tetradecenol for trials with female obliquebanded leafrollers or with (Z)- and (E)-11-tetradecenyl acetates and dodecyl acetate for trials with female redbanded leafrollers. Exposure to pheromone-permeated air delayed the onset of calling by 1 h and terminated the calling period 1 h earlier for both species compared with solvent-control exposed females. Furthermore, the total proportion of calling females was reduced by half in chambers receiving constant throughput of pheromone-permeated air compared with solvent controls. Exposure to pheromone-permeated air also significantly reduced egg-laying in both species compared with clean-air controls. Furthermore, application of the major pheromone component, (Z)-11-tetradecenyl acetate, at dosages ranging from 2 µg - 2 mg to wax-paper ovipositional substrates, deterred oviposition by females of both species. Our data suggest that application of synthetic sex-attractant pheromones for mating disruption of leafroller species may have deleterious effects on female moth behavior, which may contribute to pest control. Field investigations will need to be conducted to test this hypothesis. |
Dispersal dynamics: Distribution of lady beetles (Coleoptera: Coccinellidae)Vlastimil KØIVANEur. J. Entomol. 105 (3): 405-409, 2008 | DOI: 10.14411/eje.2008.051 This article studies coccinellid dispersal in heterogeneous environments using some hypotheses on dispersal rates that correspond to empirical observations. It is assumed that emigration rates increase with decreasing patch payoff that is measured either as the number of aphids per a lady beetle, or as the number of aphids only. Three scenarios for immigration are considered: individuals choose patches unconditionally, immigration is proportional to patch quality, and immigration is proportional to patch payoff. Coccinellid spatial distributions corresponding to these assumptions are given by a power law. Using some data from the literature on distribution of Coccinella septempunctata it is shown that the model with emigration proportional to the ratio of the number of conspecifics to aphid density and unconditional immigration rates provides the best fit when compared with the other models. This model predicts undermatching where better patches get lower consumer density when compared with the ideal free distribution. |
BOOK REVIEW: Amiet F., Herrmann M., Müller A. & Neumeyer R.: FAUNA HELVETICA 9. APIDAE 4 (Anthidum, Chelostoma, Coelioxys, Dioxys, Heriades, Lithurgus, Megachile, Osmia & Stelis). Amiet F., Herrmann M., Müller A. & Neumeyer R.: FAUNA HELVETICA 20. APIDAE 5 (Ammobates, Ammobatoides, Anthophora, Biastes, Ceratina, Dasypoda, Epeoloides, Epeolus, Eucera, Macropis, Melecta, Melitta, Nomada, Pasites, Tetralonia, Thyreus, Xylocopa).A. PØIDALEur. J. Entomol. 105 (1): 163, 2008 | DOI: 10.14411/eje.2008.023 Amiet F., Herrmann M., Müller A. & Neumeyer R.: FAUNA HELVETICA 9. APIDAE 4 (Anthidum, Chelostoma, Coelioxys, Dioxys, Heriades, Lithurgus, Megachile, Osmia & Stelis). Centre suisse de cartographie de la faune (CSCF), Neuchâtel, 2004, 272 pp., 249 figs, 117 distrib. maps. ISSN 1422-6367. Hb: ISBN 2-88414-021-2. Price CHF 45.00. |
INTERNATIONAL SYMPOSIUME.W. Evans, I. Hodek, N.G. Kavallieratos, E. Lucas, M. Mackauer, J.P. MichaudEur. J. Entomol. 105 (3): 365-368, 2008 | DOI: 10.14411/eje.2008.046 INTERNATIONAL SYMPOSIUM ECOLOGY OF APHIDOPHAGA 10, Athens, September 2007 Organized by the Benaki Phytopathological Institute, Kifissia, Attica, and the Agricultural University of Athens |
Drosophila species (Diptera: Drosophilidae) oviposition patterns on fungi: The effect of allospecifics, substrate toughness, ovipositor structure and degree of specialisationJennifer ROUQUETTE, Andrew John DAVISEur. J. Entomol. 100 (3): 351-355, 2003 | DOI: 10.14411/eje.2003.056 To determine if small-scale resource partitioning aids coexistence in fungal breeding Diptera we investigated the avoidance of interspecific larval competition by micro-resource partitioning of the host substrate in several species of Drosophila ovipositing on fungal fruiting bodies. No avoidance was detected and oviposition patterns were unaffected by the presence of allospecifics. There was a general tendency for all species to oviposit preferentially on the cap but no significant differences between species. Egg distribution was not strongly related to the sporophore's resistance to penetration measured by penetrometer and was also uncorrelated with ovipositor structure even though species had concordant suites of ovipositor characteristics with apparent specialists typified by hard and sharp ovipositors. We discuss the significance to species coexistence of the absence of micro-resource partitioning of the host. |
Substrate particle size-preference of wormlion Vermileo vermileo (Diptera: Vermileonidae) larvae and their interaction with antlionsDu¹an DEVETAKEur. J. Entomol. 105 (4): 631-635, 2008 Wormlion larvae are found in substrates consisting of fine sand or powder, implying that they may be able to distinguish between different substrates according to particle size. To estimate the effects of particle size on wormlions, the pit-building decision of the larvae of the wormlion Vermileo vermileo was observed in four substrates consisting of different sand fractions. Wormlion larvae prefer the finest sand fraction with particle size <= 230 µm. When wormlions (Vermileo vermileo) and antlions (Euroleon nostras) are placed in the same container with two different substrates, interspecific predation does not occur. In two-substrate choice tests larvae of the two species show opposite preferences for two substrates offered. While wormlion larvae readily build pits in the finest sand fraction (<= 230 µm), antlion larvae prefer coarser sand (with particle size 230-540 µm). Wormlion preference for the finest sands and powders, and antlion preference for sands of medium particle size was confirmed by field observations. Sand particle size affects the spatial distribution of sand-dwelling insect larvae and thus may reduce conflicts between heterospecifics. |
Isolation of antibacterial response genes from the dung beetle Copris tripartitus (Coleoptera: Scarabaeidae) immunized with Escherichia coliJae-Sam HWANG, Yeon-Ju KIM, Hea-Son BANG, Eun-Young YUN, Young-Tae KIM, Seong-Ryul KIM, Kwan-Ho PARK, Nam-Soon KIM, Iksoo KIM, Seok-Jo HWANG, Jae-Pil JEONEur. J. Entomol. 105 (2): 355-359, 2008 | DOI: 10.14411/eje.2008.042 Dot blot hybridization of total RNA from normal and bacteria-injected larvae of the dung beetle Copris tripartitus identified 13 cDNA clones that seem to be associated with the immune response. A cDNA encoding a dung beetle homolog of the heat shock protein HSP70 (CTHSP70) was characterized by full-length sequencing and expression pattern analysis. CTHSP70 was upregulated 4 h after bacterial injection, reached maximum level after 8 h, and declined gradually after 16 h. Our data suggest that CTHSP70 and another 12 genes are involved in the anti-microbial defense that is particularly important for dung beetle larvae living in pathogen-rich conditions. |
Morphological and molecular evidence of a possible hybrid zone of Leptidea sinapis and L. reali (Lepidoptera: Pieridae)Rudi VEROVNIK, Primo¾ GLOGOVÈANEur. J. Entomol. 104 (4): 667-674, 2007 | DOI: 10.14411/eje.2007.084 Overlapping measurements in the length of the genitalia of Leptidea sinapis/reali collected in Slovenia triggered an investigation of a possible natural hybridization between these two well known sibling species of butterflies. Random polymorphic DNA (RAPD) was used to generate species specific markers and sequences of the cytochrome oxidase subunit one gene for determination of the progeny. RAPD's clustering and mitochondrial DNA (mtDNA) phylogeny were congruent with the taxonomic placement of specimens of both species, but slightly incongruent with the results of the analysis of genital morphology. Two specimens with L. reali genitalia measurements, but genetically belonging to L. sinapis, had species specific RAPD markers of both species indicating probable hybrid origin. All the specimens with genitalia of intermediate length were also genetically assigned to L. sinapis indicating a possible one way introgression as predicted from their genitalia morphology. Leptidea sinapis was found predominantly in xerothermic habitats in Slovenia, whereas L. reali was more of a generalist except in the sub-Mediterranean region where it is limited to humid meadows. |
The value of the ITS2 region for the identification of species boundaries between Alloxysta hyperparasitoids (Hymenoptera: Charipidae) of aphidsF.J. Frank VAN VEEN, Robert BELSHAW, H. Charles J. GODFRAYEur. J. Entomol. 100 (3): 449-453, 2003 | DOI: 10.14411/eje.2003.067 1) Alloxystinae are major secondary parasitoids of aphids, important in both their ecology and pest management. 2) Two radically differing views of alloxystine taxonomy exist in the literature, in one of which the group is very diverse, in the other it consists of a few variable species. 3) We sequenced a variable nuclear gene region (ITS2) for 28 specimens of a morphologically clearly defined group which, in one view belong to a single species and in the other to four species. We find that the four putative species each carry a different unique allele with no intraspecific variation. We show that the probability of the observed distribution of alleles under the assumption of a single interbreeding population is very small and we reject the view that all specimens belong to a single biological species. 4) We discuss the implications of our results for aphid - parasitoid community ecology and the biological control of aphids with parasitoids. |
BOOK REVIEW: Blackman R.L. & Eastop V.F.: Aphids on the World's Herbaceous Plants and Shrubs.J. HOLMANEur. J. Entomol. 105 (1): 164, 2008 | DOI: 10.14411/eje.2008.024 John Wiley & Sons, Chichester, 2006, 2 volume set, 1460 pp. ISBN-10: 0-471-48973-5, ISBN-13: 978-0-471-48973-3. Price EUR 355.00. |
Size-dependent colouration in larvae of Orgyia antiqua (Lepidoptera: Lymantriidae): A trade-off between warning effect and detectability?Siiri-Lii SANDRE, Toomas TAMMARU, Triinu MÄNDEur. J. Entomol. 104 (4): 745-752, 2007 | DOI: 10.14411/eje.2007.095 While the study of colour patterns is a traditional subject of evolutionary ecology, there are various hypotheses which suffer from a lack of experimental evidence. One intriguing possibility is a trade-off between warning efficiency and detectability. After a certain size threshold, the detrimental effect of increased detectability can outweigh the benefits of warning colouration. One may thus expect corresponding patterns at the level of ontogenetic development: as juveniles grow, they should first acquire warning colouration, and then lose it again. We analysed this possibility in Orgyia antiqua, a moth species with hairy larvae which are polyphenic with respect to the intensity of warning colouration. We detected a regular change in colour patterns through larval life. Indeed, the larvae tend to display warning colouration at intermediate sizes while dull colours dominate in fully grown larvae. In aviary experiments, we confirmed that the colourful phenotype is the one that causes the strongest aversion in birds. Nevertheless, the effect was rather weak and most of the larvae were still eventually consumed when found. Unexpectedly, for human subjects, the warningly coloured larvae were harder, and not easier to find among natural vegetation, most likely due to the disruptive effect of the aposematic colour pattern. Importantly, the trend was reversed in the largest size class, suggesting that the disruptive colouration loses its advantage as the larva grows. This is consistent with the actual patterns of size-dependence of colouration. We present evidence against an alternative explanation which relates size-related change in colouration to behavioural changes prior to pupation. We conclude that even if the efficiency of the warning effect plays a role in determining the size-dependence of colouration, the pattern may be largely explained by the effects of size-dependent detectability alone. |
Repellency of conspecific and heterospecific larval residues to Hippodamia convergens (Coleoptera: Coccinellidae) ovipositing on sorghum plantsJ.P. MICHAUD, J.L. JYOTIEur. J. Entomol. 104 (3): 399-405, 2007 | DOI: 10.14411/eje.2007.059 We examined oviposition decisions by Hippodamia convergens Guérin in semi-natural arenas in the laboratory. Gravid females were presented individually with an array of four young sorghum plants, Sorghum bicolor, bearing (1) no additional stimulus, (2) an established colony of greenbug, Schizaphis graminum Rondani, (3) residues of conspecific larvae, and (4) greenbugs plus residues of conspecific larvae. Females laid no egg masses on type 3 plants, significantly fewer than expected by chance on type 4 plants, and significantly more on type 1 plants, with type 2 plants receiving expected numbers. Females laid 50% of egg masses on elements of the arena other than the plants, especially the cage screen, suggesting that females sought to distance their eggs farther from larval residues than the spacing of plants in the arena permitted (15 cm). When the experiment was repeated with plants exposed to larvae of Coleomegilla maculata DeGeer, the repellency was weaker. Once again, clean plants were the most preferred and aphids did not increase the acceptability of plants with larval residues. Nevertheless, only 18% of egg masses occurred off the plants and larval residues did not reduce the acceptability of aphid-bearing plants as did conspecific larval residues. Simultaneous choice tests conducted with individual third instars of both species revealed that C. maculata larvae consumed H. convergens eggs as readily as conspecific eggs, but H. convergens larvae preferred conspecific eggs to those of C. maculata. We conclude that H. convergens oviposition decisions are shaped by the risks of both egg cannibalism and predation. |
The effects of flooding on survivorship in overwintering larvae of the large copper butterfly Lycaena dispar batavus (Lepidoptera: Lycaenidae), and its possible implications for restoration managementColin N. NICHOLLS, Andrew S. PULLINEur. J. Entomol. 100 (1): 65-72, 2003 | DOI: 10.14411/eje.2003.014 Previous work suggests that submergence of Lycaena dispar larvae during overwintering may play a significant role in this butterfly's population dynamics. Since potential re-introduction sites in eastern England are prone to regular seasonal flooding, we further studied the species' submergence tolerance with a view to formulating management protocols conducive to larval survivorship under periodic flood conditions. Simulated flooding regimes using captive-reared larvae showed that enforced submergence has a twofold effect: firstly, a direct increase in mortality after 28 days under water and, secondly, a longer term, post-diapause increase in mortality; manifest either as an inability of larvae to resume feeding, or a failure to complete development. Additionally, there was a marked difference in the response of "early" and "late" diapause larvae; the latter generally succumbing after shorter periods under water, and suffering higher total mortalities. Behavioural investigations suggest that, if afforded the opportunity, diapausing larvae can evade submergence by climbing onto the exposed sections of partially flooded host plants. Significantly, survival on partially flooded plants was found to be comparable to that on unflooded controls. Further re-introductions of L. dispar in the U.K. will probably necessitate a direct translocation of wild Dutch stock. As the flood tolerance of this source population remains largely undetermined, and given that re-introduction site hydrology will be generally unamenable to conservation-oriented manipulation, it is recommended that restoration management be directed towards creating structural diversity in the vegetation of overwintering habitats, thereby providing potential "flood refugia" for hibernating larvae. |
Physiological state of female and light intensity affect the host-plant selection of carrot psyllid, Trioza apicalis (Hemiptera: Triozidae)Anne NISSINEN, Lina KRISTOFFERSEN, Olle ANDERBRANTEur. J. Entomol. 105 (2): 227-232, 2008 | DOI: 10.14411/eje.2008.032 We have studied the effect of different light gradient regimes on host-plant selection of the carrot psyllid, Trioza apicalis Förster. In both a strong and a weak light gradient, carrot psyllids preferred a carrot leaf placed in higher light intensity. When the choice was between the host (carrot Daucus carota L.) and a non-host (barley Hordeum vulgare L.) virgin adults settled significantly more often on non-host in higher light intensity than on carrot in lower light intensity. In a weak light gradient, none of the gravid females settled on a non-host. In an experiment without light gradient, gravid females showed a preference for carrot, whereas virgin females settled approximately equally on Norway spruce Picea abies Karst. (winter shelter plant) and carrot. Our results show that virgin and gravid individuals have different host-plant selection behaviour, and that they are sensitive to small differences in light intensity. Both factors can create a source of variation in behavioural assays, and should be taken into consideration in future experiments with this and probably also related species. Our results suggest that carrot psyllids can utilize visual cues (light intensity or wavelength) in host-plant selection, and the role of visual cues should be more thoroughly studied. |
The influence of female oviposition strategy on sibling cannibalism in the ladybird beetle Harmonia axyridis (Coleoptera: Coccinellidae)Naoya OSAWAEur. J. Entomol. 100 (1): 43-48, 2003 | DOI: 10.14411/eje.2003.009 I hypothesized that sibling cannibalism is one of maternal investment in that a female controls sibling cannibalism. To test the hypothesis, I conducted a laboratory experiment and field observations to investigate sibling cannibalism in relation to cluster size and cluster site in the ladybird beetle, Harmonia axyridis Pallas. In the laboratory experiment, cluster size significantly affected the number of cannibalized eggs per cluster (R2 = 0.516), while cluster size was significantly affected by the oviposition interval. Furthermore, there was a marginally significant positive relationship between cluster size and the percentage of sibling cannibalism per cluster. In the field, cluster size and the direct distance from a cluster site to an aphid colony (an indicator of intensity of non-sibling cannibalism) significantly affected the number of cannibalized eggs per cluster (R2 = 0.472). Furthermore, there was a significant positive relationship between the direct distance from a cluster to the nearest aphid colony and cluster size. However, there was not a significant relationship between the distance and the percentage of sibling cannibalism. These results may be caused by the weakness of the female's power to control sibling cannibalism. Thus, a female H. axyridis controls cluster size through the intensity of non-sibling cannibalism, which may be one of oviposition strategies in this species. |
BOOK REVIEW: Amiet F.: FAUNA HELVETICA 23. VESPOIDEA 1 (Mutillidae, Sapygidae, Scoliidae, Tiphiidae).P. BOGUSCHEur. J. Entomol. 105 (5): 949-950, 2008 | DOI: 10.14411/eje.2008.122 Centra Suisse de Cartographie de la Faune (CSCF/SZKF), Schweizerische Entomologische Gesselschaft (SES/SEG), Neuchatel, 2008, 86 pp., 95 drawings, 24 photographs, 27 distribution maps. ISBN 978-2-88414-035-5, ISSN 1422-6367. Price CHF 30.00. |
Myrmica sabuleti (Hymenoptera: Formicidae) not necessary for the survival of the population of Phengaris (Maculinea) arion (Lepidoptera: Lycaenidae) in eastern Poland: Lower host-ant specificity or evidence for geographical variation of an endangered social parasite?Marcin SIELEZNIEW, Anna M. STANKIEWICZEur. J. Entomol. 105 (4): 637-641, 2008 Larvae and pupae of the obligatorily myrmecophilous Phengaris (Maculinea) arion were found for the first time in nests of Myrmica rugulosa, M. hellenica and M. schencki at a site in eastern Poland. M. sabuleti, commonly considered as a major host of the butterfly and whose abundance is vital for the survival of P. arion populations, was shown to be very rare and not used. Estimated mean density of Myrmica nests was very low, which suggests that relatively vast areas are necessary to support a viable population of P. arion in similar sandy habitats. This may explain the decline and rarity of the butterfly in the whole region, even though its relationships with ants seem not to be very specific there. |
Cereal aphids (Hemiptera: Aphidoidea) in Serbia: Seasonal dynamics and natural enemies®eljko TOMANOVIÆ, Nickolas G. KAVALLIERATOS, Petr STARÝ, Olivera PETROVIÆ-OBRADOVIÆ, Christos G. ATHANASSIOU, Ljubi¹a ®. STANISAVLJEVIÆEur. J. Entomol. 105 (3): 495-501, 2008 | DOI: 10.14411/eje.2008.064 During 1989-2006 the number of live aphid, mummies, aphid specialist predators and their parasitoids in cereal fields in Serbia were recorded. S. avenae and M. dirhodum were the most common, both on wheat and rye crops. Maximum numbers of cereal aphids were detected between the end of May and the middle of June. A low percentage of mummified aphids was recorded during May and June, but increased rapidly at the beginning of July, when aphids left the wheat crop. Here, we record over 60 species of cereal aphid natural enemies, including primary and secondary parasitoids, aphid specific predators and a wide spectrum of their parasitoids in Serbian cereal crop systems. Aphidius uzbekistanicus Luzhetzki, Aphidius rhopalosiphi De Stefani, Aphidius ervi Haliday and Praon gallicum Starý were the most abundant species of primary parasitoids. Of the secondary parasitoids, six species were dominant with Asaphes suspensus (Nees) and Dendrocerus carpenteri (Curtis) generally the most often recorded. Coccinella septempunctata L. was the most abundant coccinellid and syrphid flies were represented by 11 species, two of which, Sphaerophoria scripta (L.) and Episyrphus balteatus (DeGeer), were the most common. |
BOOK REVIEW: Jolivet P., Santiago-Blay J.A. & Schmitt M. (eds): RESEARCH ON CHRYSOMELIDAE. VOL. 1.J. BEZDÌKEur. J. Entomol. 105 (5): 951, 2008 | DOI: 10.14411/eje.2008.123 Brill, Leiden-Boston, 2008, 430 pp., 38 colour plates. ISBN 978-90-04-15204-5. Price EUR 169.00/USD 270.00. |
A new genus of isophlebioid damsel-dragonflies with "calopterygid"-like wing shape from the Middle Jurassic of China (Odonata: Isophlebioidea: Campterophlebiidae)André NEL, Di-Ying HUANG, Qi-Bin LINEur. J. Entomol. 105 (4): 783-787, 2008
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BOOK REVIEW: De Prins W. & De Prins J.: GRACILLARIIDAE (LEPIDOPTERA) - IN: WORLD CATALOGUE OF INSECTS 6.J. JARO©Eur. J. Entomol. 105 (2): 363, 2008 | DOI: 10.14411/eje.2008.044 Apollo Books, Stenstrup, 2005, 502 pp. ISBN 87-88757-64-1. Price DKK 780.00. |
BOOK REVIEW: Czechowski W., Radchenko A. & Czechowska W.: The Ants (Hymenoptera, Formicidae) of Poland.J. FROUZEur. J. Entomol. 100 (3): 336, 2003 | DOI: 10.14411/eje.2003.053 Museum and Institute of Zoology Polish Academy of Sciences, Warszawa, 2002, pp. 200 + 1 Table |
Role of volatile and contact pheromones in the mating behaviour of Bagrada hilaris (Heteroptera: Pentatomidae)Salvatore GUARINO, Claudio DE PASQUALE, Ezio PERI, Giuseppe ALONZO, Stefano COLAZZAEur. J. Entomol. 105 (4): 613-617, 2008 Volatiles and contact pheromones involved in the mating behaviour of the Painted bug, Bagrada hilaris Burmeister (Heteroptera: Pentatomidae), were investigated in behavioural and chemical experiments. Vertical open Y-shaped olfactometer bioassays showed that odour from males attract females but not males, while that from females did not attract either gender. Adult females were also attracted by hexane extracts of volatile compounds collected from males. In open arena bioassays, males displayed the characteristic steps of courtship behaviour in the presence of virgin females. Such courtship behaviour was displayed in the presence of females killed by freezing, but not in the presence of freeze-killed females washed with hexane. Gas chromatography-mass spectrometry (GC-MS) analysis of volatile compounds produced by cohorts of 20 B. hilaris adults and collected over 48 h showed that both males and females produce the compounds nonanal, decanal and (E)-2-octenyl acetate. Of these compounds males produce significantly more (E)-2-o-octenyl acetate, i.e. 186.74 ng and 67.53 ng for males and females respectively. These findings indicate this compound is possibly a long range volatile pheromone, and a complex lipophilic fraction of the adult cuticle possible contact pheromone involved in short range courtship behaviour. |
BOOK REVIEW: Domínguez E., Molineri C., Pescador M.L., Hubbard M.D. & Nieto C.: EPHEMEROPTERA OF SOUTH AMERICAT. SOLDÁNEur. J. Entomol. 105 (4): 718, 2008 Pensoft Publishers, Sofia-Moscow, 2006, vi + 640 pp. ISSN 13127276/ ISBN-10: 954-642-259-2, ISBN-13: 978-954-642-259-0. Price EUR 115.00. |
Conservation biological control of spirea aphid, Aphis spiraecola (Hemiptera: Aphididae) on apple by providing natural alternative food resourcesMark W. BROWN, Clarissa R. MATHEWSEur. J. Entomol. 105 (3): 537-540, 2008 | DOI: 10.14411/eje.2008.071 Enhancing biological control in orchards is an efficient way to control insect pests. This study investigates the possibility of increasing biological control of spirea aphid by providing alternate food resources, in the form of peach extrafloral nectar, to adult Harmonia axyridis, its primary predator. Two pairs of apple orchards, each having one interplanted with 50% trees bearing extrafloral nectar and one a monoculture, were studied for aphid and predator populations from 1999 to 2005. There were no differences in spirea aphid or predator populations between interplanted and monoculture orchards. However, H. axyridis adults arrived earlier in the interplanted than in the monoculture orchards. In another apple orchard, the effect of peach extrafloral nectar on sentinel spirea aphid colonies surrounding a cluster of potted peach trees, or a cluster of apple trees as a control, was tested in 2007. Only the closest spirea colonies to the potted peach trees, trees within 3 m, showed an increase in biological control. Although there was some indication of enhancement of predation by adult H. axyridis on spirea aphids, adding alternative food resources in the form of peach trees bearing extrafloral nectar resulted in no detectable increase in biological control. |
Moist habitats are essential for adults of the Antarctic midge, Belgica antarctica (Diptera: Chironomidae), to avoid dehydrationJoshua B. BENOIT, Giancarlo LOPEZ-MARTINEZ, Michael A. ELNITSKY, Richard E. LEE, David L. DENLINGEREur. J. Entomol. 104 (1): 9-14, 2007 | DOI: 10.14411/eje.2007.002 Desiccation resistance of adult males and females of the midge, Belgica antarctica (Diptera: Chironomidae) was evaluated to determine how this short-lived stage maintains water balance in the dry Antarctic environment. Both sexes had slightly lower water content (≈60%) and a higher dehydration tolerance (>30% water loss) than most other insects. Water loss rates were high and increased rapidly at temperatures above 15°C, indicating that the adult midges are more hygric than many other polar terrestrial arthropods. Water gain was accomplished by free water uptake with minimal or no contribution from absorption of water vapor or metabolic water production. Parameters related to water balance did not differ among populations from different islands. Overall, the high water requirements of the adult midge appear to be a significant challenge and presumably dictate that the adult midges must emerge during the brief period when free water is readily available and seek protected microhabitats that facilitate water retention. |
Book Review: The Caddisfly Family Phryganeidae (Trichoptera).BOTOSANEANU L.Eur. J. Entomol. 96 (4): 354, 1999 Wiggins G.B.: The Caddisfly Family Phryganeidae (Trichoptera). University of Toronto Press, Toronto-Buffalo-London, 1998, 306 pp. |