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The aphidophagous predator Harmonia axyridis (Coleoptera: Coccinellidae) in Greece, 1994-1999Dimitrios C. KONTODIMAS, George J. STATHAS, Aggeliki F. MARTINOUEur. 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. |
A revision of Metriorrhynchus from the Philippines with molecular evidence of an Australian origin of the Oriental Metriorrhynchus fauna (Coleoptera: Lycidae)Ladislav BOCÁK, Kiyoshi MATSUDA, Takashi YAGIEur. J. Entomol. 103 (1): 115-126, 2006 | DOI: 10.14411/eje.2006.017 The Metriorrhynchus fauna of the Philippines is revised. All known species are redescribed and seven new species are added: M. isarogensis sp. n., M. menieri sp. n., M. mindanaoensis sp. n., M. newbataanensis sp. n., M. ochii sp. n., M. palawanensis sp. n., and M. takedai sp. n. Additionally, M. yoshioi sp. n. is described from Sulawesi. Xylobanus longissimus Pic, 1922 is transferred to Metriorrhynchus, and Metriorrhynchus pallidus (Dalman in Schoenherr, 1818) is transferred to Leptotrichalus Kleine, 1925. The dispersal routes and speciation of Metriorrhynchus from the Philippines, Sulawesi and the Oriental Region were studied using mtDNA markers. One dispersal event is supposed for establishing of the Greater Sunda Islands fauna and another one for the Philippine fauna. Both faunas underwent speciation in the respective areas and all species show high degree of endemism. The Metriorrhynchus in Palawan is of Philippine origin in contrast with the tectonic history of Palawan and its connection with Borneo during the last glacial maximum. |
Regulation of the development of flight muscles in long-winged adults of the flightless bug Pyrrhocoris apterus (Heteroptera: Pyrrhocoridae)Radomír SOCHA, Jan ©ULAEur. J. Entomol. 105 (4): 575-583, 2008 We studied the development of the indirect flight muscles and reproductive organs in long-winged (macropterous) adults of the flightless bug Pyrrhocoris apterus (L.) and the factors involved in flight muscles histolysis by means of total protein analysis. Both the extirpation of the corpus allatum, an endocrine gland that is the sole source of juvenile hormone, and sham operation accelerated histolysis and decreased the level of the total protein content of the flight muscles to the same extent. Degeneration of flight muscles was not a result of allatectomy but rather a consequence of injury, followed by resumption of enhanced food intake, because it was stimulated also by the removal of wings. Transfer of penultimate instar larvae to a diapause-inducing short-day photoperiod did not prevent imaginal growth and histolysis of flight muscles, but inhibited growth of ovaries in females and maturation of accessory glands in adult males. Thus inactivation of the corpus allatum in diapausing macropters does not prevent imaginal growth of their flight muscles. Application of a high dose of methoprene to the surface of intact long-day macropterous adults induced precocious histolysis of flight muscles and growth of ovaries in females and accessory glands in males. Prolonged starvation of macropterous adults had only a small effect on the histolysis of their flight muscles. The results indicate that imaginal growth and histolysis of indirect flight muscles in macropterous individuals of P. apterus are largely juvenile hormone-independent processes that are programmed to occur spontaneously, but can be affected by various internal and external factors. |
Cereal aphids (Hemiptera: Aphidoidea) in Serbia: Seasonal dynamics and natural enemies®eljko TOMANOVIĆ, Nickolas G. KAVALLIERATOS, Petr STARÝ, Olivera PETROVIĆ-OBRADOVIĆ, Christos G. ATHANASSIOU, Ljubiąa ®. STANISAVLJEVIĆEur. 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. |
Diversity of ground beetles (Coleoptera: Carabidae) and spiders (Araneae) in roadside verges with grey hair-grass vegetationJinze NOORDIJK, André P. SCHAFFERS, Karlè V. SÝKORAEur. J. Entomol. 105 (2): 257-265, 2008 | DOI: 10.14411/eje.2008.036 Roadside verges in densely populated areas are often a significant addition to the total semi-natural area and as such may contribute to the conservation of biodiversity. Furthermore, they can enhance the ecological cohesion of a region, especially when the existing nature reserves are small and/or highly fragmented. We investigated the occurrence of ground beetles and spiders in six highway verges with grey hair-grass vegetation in the Veluwe region, The Netherlands. Total species number in the verges was similar to the values found in nearby nature reserves with comparable vegetation, but the ground beetles tended to be more abundant in the reserves. Many stenotopic species were present in the verges, confirming the significant conservation value of this habitat. However, compared with the nature reserves, there were fewer species of stenotopic ground beetles and the stenotopic spiders were less abundant in the verges. From our knowledge of the biology and ecology of the species captured it seems likely that this is attributable to differences in "habitat quality". In the verges, species preferring bare sand are scarcer, and the weighted mean body length of ground beetles is shorter than in nature reserves. This suggests that the sward in the road verges is too dense and the suitable vegetation too patchy to sustain some of the stenotopic species. Habitat analyses support this contention: Compared with the nature reserves, the verges had proportionally less bare sand, more herb and tree cover and the vegetation patches were smaller. The strategy suggested to promote stenotopic species entails removing encroaching trees and shrubs from the verges in order to expand the nutrient-poor zone and (re-)create pioneer conditions. Subsequent management should aim at further improving the road verges as extensions of nutrient-poor habitat. |
The effects of Pleistocene glaciations on the phylogeography of Melitaea cinxia (Lepidoptera: Nymphalidae)Niklas WAHLBERG, Ilik SACCHERIEur. J. Entomol. 104 (4): 675-684, 2007 | DOI: 10.14411/eje.2007.085 Partial (600 bp) sequences of mitochondrial cytochrome oxidase I (COI) gene were used to infer the phylogeography of Melitaea cinxia (Lepidoptera: Nymphalidae) across the entire distributional range of the species, encompassing north Africa and Eurasia. Cladistic analysis of 49 distinct haplotypes (haplotype and nucleotide diversity were 0.95 and 0.027, respectively) revealed strong phylogeographic structure in M. cinxia, characterised by four major clades: Morocco; Western (Iberia, France, Italy); Central (central and northern Western Europe, Balkans, Greece, Anatolia, Levant); and Eastern (eastern Baltic, Urals, Iran, Siberia, China); separated by average pairwise distances of beween 2 and 6 percent. This pattern is consistent with the location of southern glacial refugia in the Iberian, Italian and Balkan peninsulas, as well as multiple eastern refugia. The Western clade is further structured into south-central Iberian, northern Iberian (and French) and southern Italian sub-clades; and the Eastern clade into Near Eastern and Far Eastern sub-clades; with weaker phylogeographical concordance within the Central clade, except for a large area in central and northern Western Europe which is monomorphic for COI haplotype. The Baltic and eastern Europe have been primarily colonized by the Far Eastern sub-clade, rather than the Central (Balkan) clade, highlighting the importance of including Near and Far Eastern populations in phylogeographic studies of Palearctic species. Maps showing the extent of clades and sub-clades suggest several regions of secondary contact and possible hybridization. Interspecific comparison of representative M. cinxia haplotypes supports a monophyletic origin of all M. cinxia. |
Faunal patterns in Tuscan archipelago butterflies (Lepidoptera): The dominant influence is recent geography not paleogeographyLeonardo DAPPORTO, Alessandro CINIEur. J. Entomol. 104 (3): 497-503, 2007 | DOI: 10.14411/eje.2007.070 The aim of this paper is to examine whether current and/or Pleistocene geography affect the species richness and composition of Tuscan archipelago butterflies. This archipelago is located between Tuscany (Italy) and Corsica (France). Faunistic data was obtained from the literature and surveys. Our data revealed that contemporary geography is the most important factor determining the species richness and faunal composition of Tuscan archipelago butterflies. Indeed, current area and isolation of the islands are the only predictors significantly correlated with species richness. Paleogeographic features of the archipelago are not significantly correlated with species richness. Multidimensional scaling revealed patterns similar to those reported for other living groups. Specifically, Capraia and Montecristo group together with Corsica, while Elba, Giglio, Pianosa, Gorgona, Giannutri and the fossil island of Monte Argentario group with the Tuscan mainland. Recent geography seems to affect the faunal composition. Indeed Mantel test indicates that the similarity in the faunal composition of the Tuscan Archipelago islands is mainly related to present-day island characteristics and their relative distance from Tuscany and Corsica. Our results are similar to those recently obtained for Aegean archipelago butterflies. |
A new Upper Cretaceous species of Chresmoda from Lebanon - a latest representative of Chresmodidae (Insecta: Polyneoptera inc. sed.): first record of homeotic mutations in the fossil record of insectsAndré NEL, Dany AZAR, Xavier MARTÍNEZ-DELCLOS, Edouard MAKHOULEur. J. Entomol. 101 (1): 145-151, 2004 | DOI: 10.14411/eje.2004.019 The most recent representative of the semi-aquatic insect family Chresmodidae is described from the Lebanese Cenomanian marine lithographic limestone. Its highly specialized legs, with a high number of tarsomeres, never observed in other orders of insects, were probably adapted for water surface skating. We hypothesize the occurrence of a unique, extraordinary "antenna" mutation affecting the distal part of the legs of the Chresmodidae, maybe homeotic or affecting some genes that participate in the leg development and segmentation. The Chresmodidae had a serrate ovipositor adapted to endophytic egg laying in floating or aquatic plants. They were probably predaceous on nektonic small animals. As the Chresmodidae and the aquatic water skaters of the bug families Veliidae and Gerridae were contemporaneous during at least the Lower Cretaceous, these insects probably did not cause the extinction of this curious group. |
Establishment of ant communities in forests growing on former agricultural fields: Colonisation and 25 years of management are not enough (Hymenoptera: Formicidae)Wouter DEKONINCK, Konjev DESENDER, Patrick GROOTAERTEur. J. Entomol. 105 (4): 681-689, 2008 Ants are often considered as good indicators of change of management in different habitats. They have been used sporadically to evaluate large scale transformations involving reafforestation. In the present study, the ant assemblages at 15 forest sites are compared. The sites differ in history, age and forest management. Our results show that there are clear changes in ant assemblages with developmental stage but even after 25 years not all forest species are present. Natural succession and planting of trees with or without any other management, resulted in only open country species, and some from forest and wet grassland colonizing these new forests. Sometimes gynes of target forest species arrived in new forests from nearby mature forest, but apparently were unable to start a colony. We attribute this findings to the lack of appropriate vegetation structure and litter characteristics, which determines the forest ant fauna, more than the dispersal of ant gynes. Further investigations should enable us to predict if these conditions can be produced by 50-100 or more years of forest succession and adequate management. |
Susceptibility of endemic and exotic North American ladybirds (Coleoptera: Coccinellidae) to endemic fungal entomopathogensTed E. COTTRELL, David I. SHAPIRO-ILANEur. J. Entomol. 105 (3): 455-460, 2008 | DOI: 10.14411/eje.2008.058 We tested the laboratory susceptibility of four endemic and two exotic species of North American Coccinellidae to a single rate (2.5 × 105 conidia/ml) of Beauveria bassiana derived from different sources. The endemic species Olla v-nigrum, Cycloneda munda and Hippodamia convergens were susceptible to B. bassiana Isolate B which was originally isolated from O. v-nigrum and the rate assayed was known to represent the LC50 against O. v-nigrum. However, neither the endemic C. maculata nor the exotic species Harmonia axyridis and Coccinella septempunctata were susceptible to this isolate at this rate. Additionally, all species of endemic and exotic Coccinellidae used in these assays were resistant to B. bassiana strain GHA and BbAR1 at that rate. We discuss the implications of these results in regard to the establishment of exotic species in new habitats. |
Bladder grasshoppers (Caelifera: Pneumoridae) contain three adipokinetic peptidesGerd GÄDEEur. J. Entomol. 105 (2): 211-217, 2008 | DOI: 10.14411/eje.2008.030 The corpora cardiaca (CC) of the pneumorid grasshopper species Bullacris discolor contain at least one substance that causes hyperlipaemia in the migratory locust. Isolation of neuropeptides belonging to the adipokinetic hormone (AKH) family was achieved by single-step reversed-phase high performance liquid chromatography (RP-HPLC) of CC extracts and monitoring tryptophan fluorescence. The material of the bladder grasshopper showed three distinct fluorescence peaks with adipokinetic activity in the migratory locust. The peptide sequences were identified by Edman degradation after the N-terminal pyroglutamate residue had been cleaved off enzymatically, and the exact peptide masses were determined by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry. Moreover, the assigned peptides were synthesised and natural and synthetic peptides were compared in their behaviour in RP-HPLC. B. discolor stores three AKH peptides in its CC: two of those are octapeptides, Schgr-AKH-II (pELNFSTGWamide) and Peram-CAH-II (pELTFTPNWamide), whereas the third peptide is a decapeptide, Phyle-CC (pELTFTPNWGSamide. The concentration of carbohydrates in the haemolymph of B. discolor is about 3 times higher than the lipid concentration. Upon injection with synthetic Schgr-AKH-II no adipokinetic or hypertrehalosaemic effect was measurable. A literature survey appears to indicate that an active role of these AKH peptides in substrate mobilisation is only overtly displayed in those caeliferan species that undertake well-defined flight periods. |
Silver-negative NORs in Pamphagus ortolaniae (Orthoptera: Pamphagidae)Roberto VITTURI, Antonella LANNINO, Caterina MANSUETO, Valentina MANSUETO, Mariastella COLOMBAEur. J. Entomol. 105 (1): 35-39, 2008 | DOI: 10.14411/eje.2008.004 The present paper reports some cytogenetic peculiarities observed in the Ag-NORs of Pamphagus ortolaniae chromosomes, the unusual behaviour of ribosomal sites after silver staining and the intense Ag-positive reaction of centromeric regions at spermatogonial metaphase and spermatocyte metaphase I and II. Moreover, a conclusive identification and localization of all the ribosomal clusters is provided by using heterologous rDNA FISH on spermatocyte chromosomes. 18S-28S rDNA mapped on a single chromosome pair and resulted multiclustered along the chromosomal body in three distinct serial regions, r1, r2 and r3. Surprisingly, these areas were scarcely (r1) or never (r2 and r3) detectable by silver impregnation. As in other Orthoptera and many groups of arthropods, FISH with the pentamer (TTAGG)n as the probe labelled the telomeres of all chromosomes. |
Odour-mediated sexual attraction in nabids (Heteroptera: Nabidae)Steffen ROTH, Arne JANSSEN, Maurice W. SABELISEur. J. Entomol. 105 (1): 159-162, 2008 | DOI: 10.14411/eje.2008.022 In many insects, mate finding is mediated by volatile sex pheromones, but evidence in nabids is still fragmentary. The role of odour-mediated sexual attraction in two nabid species, Nabis pseudoferus and N. rugosus, was studied in a Y-tube olfactometer. Females of the two species were significantly attracted by odours of conspecifics males, and males of N. rugosus, but not of N. pseudoferus, were attracted by odours of conspecific females. Odours of conspecifics of the same gender were unattractive. These results suggest the existence of male pheromones in both species and a different female pheromone in N. rugosus. |
Distribution and diversity of wheat aphid parasitoids (Hymenoptera: Braconidae: Aphidiinae) in IranEhsan RAKHSHANI, ®eljko TOMANOVIĆ, Petr STARÝ, Ali-Asghar TALEBI, Nickolas G. KAVALLIERATOS, Abbas-Ali ZAMANI, Srdjan STAMENKOVIĆEur. J. Entomol. 105 (5): 863-870, 2008 | DOI: 10.14411/eje.2008.114 Eleven species of parasitoids were found to attack 7 species of wheat aphids in Iran. The Simpson's Index of diversity (D) used to compare the aphidiine diversity in various cereal crop systems in geographically different regions of Iran ranged from 0.197 to 0.488, depending on locality. There were significant differences among species diversities at different altitudes. The central highlands (1000-1500 meters above mean sea level) were the areas with the most diverse aphid parasitoid complex, differing significantly from that at lower and higher altitudes. We found that altitude explained about 10% of the cereal aphid parasitoid distribution pattern in Iran. Species of the genus Aphidius Nees were the most abundant and widely distributed. These were Aphidius rhopalosiphi De Stefani, Aphidius uzbekistanicus Luzhetski, Aphidius colemani Viereck and Aphidius matricariae Haliday. A. uzbekistanicus, Ephedrus plagiator (Nees) and Ephedrus persicae Froggat were encountered mainly on the plains at lower altitudes. Diuraphis noxia (Kurdjumov) was mainly recorded at higher altitudes in Iran along with its dominant parasitoid species, Diaeretiella rapae (MIntosh). The fact that Iran is close to the presumed area of D. noxia origin (Central Asian submountains) could be very important in further biological control efforts against this pest aphid. According to our results, Aphidius ervi Haliday is a very rare parasitoid of cereal aphids in Iran, which contrast with its high abundance in Europe and North America. |
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. |
The importance of termites (Isoptera) for the recycling of herbivore dung in tropical ecosystems: a reviewBernd P. FREYMANN, Robert BUITENWERF, Og DESOUZA, Han OLFFEur. J. Entomol. 105 (2): 165-173, 2008 | DOI: 10.14411/eje.2008.025 While the key role of termites in the decomposition of litter in the tropics has been acknowledged for a long time, much less information exists on their importance in the recycling of dung of primary consumers, especially herbivores. A review of published studies shows that a diverse group of termites (at least 126 species) has been reported to feed on a wide range of mammalian dung (18 species). Predominantly, wood-feeding and polyphagous wood-litter feeding species were found to feed also frequently on dung. Moreover, we found that termites can quickly remove large amounts of mammalian dung, especially in the dry season, when on average about 1/3 of the dung deposited in a given habitat is removed by termites within one month (with the highest rates observed in savannas). No distinctive preference for mammalian dung over other organic food sources was observed for fungus-growing termites (Macrotermitinae), whereas the majority of the non-fungus growing taxa studied prefer dung over other food. As termites bring large quantities of dung below the soil surface, disturb and enrich soils with nutrients, dung feeding by termites appears to be a previously underestimated process important in the functioning of tropical ecosystems. |
Polymorphic microsatellite loci in the endangered butterfly Lycaena helle (Lepidoptera: Lycaenidae)Jan Christian HABEL, Aline FINGER, Marc MEYER, Thomas SCHMITT, Thorsten ASSMANNEur. J. Entomol. 105 (2): 361-362, 2008 | DOI: 10.14411/eje.2008.043 Six polymorphic microsatellite loci were isolated in the endangered butterfly Lycaena helle. Five of them provided interpretable results. We detected four to 34 alleles per locus in a total of 235 samples (males and females) collected from meadows in the Ardennes-Eifel (Germany, Luxemburg and Belgium) and the Westerwald (Germany). We collected one leg for DNA-extraction as a non-lethal method. The expected heterozygosities ranged from 48.6% to 83.1%, depending on the locus analysed. These markers are currently being used in our studies of the species´ phylogeography over its western Palearctic distribution area and for the analysis of the conservation status of the fragmented populations in Central Europe. |
Genetic diversity in European pollen beetle, Meligethes aeneus (Coleoptera: Nitidulidae), populations assessed using AFLP analysisNadiya KAZACHKOVA, Johan MEIJER, Barbara EKBOMEur. J. Entomol. 105 (5): 807-814, 2008 | DOI: 10.14411/eje.2008.107 The pollen beetle (Meligethes aeneus) is one of the most important insect pests of oilseed rape (Brassica napus), and extensive use of insecticides is required to protect crop yields. To meet the challenges set by agricultural demands for more sustainable production and changing climate more information about pest biology and population genetics is needed. Using genomic Amplified Fragment Length Polymorphism (AFLP) analysis, DNA polymorphism was studied in 14 field populations of pollen beetles, collected during 2004 in six European countries (Denmark, France, Finland, Germany, Sweden, and UK). Using one primer combination 410 polymorphic DNA fragments were obtained based on analysis of single beetles. AFLP profiles were analysed with similarity measures using the Nei and Li coefficient and dendrograms generated. Dendrograms constructed from distance matrices revealed clustering by population origin and assignment analysis generally supported the genotype classification. Principal component analysis of the fourteen groups resulted in wide dispersion but also connections between some groups. Statistical analysis using AMOVA showed that the levels of genetic variation within populations explained most of the variation. Migrant analysis suggested a low level of gene flow between pollen beetle populations at different geographical locations indicating little long range dispersal of pollen beetles. However, a Mantel test found no correlation between genetic and geographical distance. Apparently genetic differentiation among populations has a complex background and may involve factors such as local adaptation and founder effects. |
Light-induced behavioural effects on the locomotor activity rhythm of the blow fly, Calliphora vicina (Diptera: Calliphoridae)David S. SAUNDERS, Bronislaw CYMBOROWSKIEur. J. Entomol. 105 (4): 585-590, 2008 Under continuous light (LL) of low intensity (up to 2.0 lux), the free-running period of the blow fly activity rhythm lengthened for flies whose initial τDD was less than about 25 h, but shortened for longer-period flies. Light intensity above about 2.0 lux led to an overt behavioural arrhythmicity. A comparison of phases of the oscillation after LL as a function of phases before LL, however, indicated that the oscillation continued its motion even though overt behaviour was arrhythmic. As the intensity during LL increased to 48 lux, phases after LL became centred on a narrow range close to CT 12. Extended periods of brighter light are considered to have two effects: (a) an exogenous "masking" effect occurring at intensities greater than about 2.0 lux, and (b) at intensities between about 2.0 and 48 lux, a gradual resetting of the covert oscillator to CT 12. Between 2.0 and 48 lux, therefore, the circadian oscillation governing locomotor activity in C. vicina continues its motion despite the superficial arrhythmicity in behaviour. |
Arrhythmic adult ecdysis but rhythmic emergence from the host chorion in Trichogramma embryophagum (Hymenoptera: Trichogrammatidae)Sergey Ya. REZNIK, Natalia D. VOINOVICH, Nina P. VAGHINA, Svetlana G. KARPOVAEur. J. Entomol. 105 (1): 81-85, 2008 | DOI: 10.14411/eje.2008.011 In many insect species with a pupa covered by various "shells" (puparium, host remains, etc.) pupal-adult ecdysis and emergence to the open air represent two discrete steps. However, in Trichogramma, as well as in other insect parasitoids, these two processes have never been studied separately. We investigated the temporal pattern of pupal-adult ecdysis and of adult emergence from the host chorion in Trichogramma embryophagum Hartig (Hymenoptera: Trichogrammatidae) in laboratory conditions (12L : 12D, 20°C). Adult ecdysis was arrhythmic, while adult emergence showed a strong rhythmicity. The time lag between ecdysis and emergence varied from one to almost two days, depending on the circadian time of the ecdysis. The proportion of ecdysed adults that stayed in the host chorion ranged up to 60% (just before the highest peak of emergence). The cumulative percentage of ecdysed adults gradually increased with time, independently of whether the light was turned on in accordance with the entrained circadian rhythm or 4 h earlier. This arrhythmic ecdysis could be explained by the fact that the ecdysed adults get into a well protected space inside the host chorion and the timing of this event is adaptively neutral. |
Microsatellites for the highly invasive Cameraria ohridella (Lepidoptera: Gracillariidae) and their amplification in related speciesNeus MARI MENA, Romain VALADE, Emmanuelle MAGNOUX, Sylvie AUGUSTIN, Carlos LOPEZ-VAAMONDEEur. J. Entomol. 105 (5): 945-948, 2008 | DOI: 10.14411/eje.2008.121 A set of six polymorphic microsatellite markers was developed for the highly invasive horse chestnut leaf-mining moth, Cameraria ohridella. For 96 positive clones, six polymorphic microsatellites with conserved flanking regions were identified. The average number of alleles per locus was eight (range from three to 12). Two of these loci showed significant heterozygosity deficits due to null alleles. The remaining four loci did not depart from Hardy-Weinberg equilibrium. In addition, all six loci were amplified for 20 other gracillariid species belonging to eight different genera, including another invasive species Phyllonorycter platani. These are the first microsatellite markers described for a species within the lepidopteran family Gracillariidae. |
The two spotted spider mite, Tetranychus urticae (Acari: Tetranychidae), alternative prey for the lacewing Dichochrysa prasina (Neuroptera: Chrysopidae)Maria L. PAPPAS, Georgios D. BROUFAS, Dimitris S. KOVEOSEur. J. Entomol. 105 (3): 461-466, 2008 | DOI: 10.14411/eje.2008.059 The predatory lacewing Dichochrysa prasina Burmeister can feed and reproduce on various aphid species. However, other species such as the two spotted spider mite Tetranychus urticae Koch may serve as an alternative prey for this predator in the field in periods when the population density of aphids is low. In peach orchards in Northern Greece D. prasina larvae are often found during the summer months on leaves infested with T. urticae. The development and reproduction of D. prasina fed on T. urticae at a series of different constant temperatures were studied. The percentages of D. prasina larvae that completed their development when fed on T. urticae ranged from 12 to 60% depending on the temperature over the range from 20 to 30°C, whereas at temperatures above 33°C no larvae survived. Longevity and egg production of D. prasina females fed during the larval stages on T. urticae were also determined and certain demographic parameters such as the intrinsic rate of increase (rm), mean generation time and net reproductive rate were estimated. Over the range of temperatures from 20 to 27°C, the rm values were not significantly different and varied from 0.06629 to 0.07030. Based on the results of the present study, the possible effect of the availability of T. urticae as prey for D. prasina during summer, when its main prey species is scarce, is discussed. |
Origin of Jordanian honeybees Apis mellifera (Hymenoptera: Apidae) using amplified mitochondrial DNAShahera ZAITOUN, Dhia S. HASSAWI, Wesam SHAHROUREur. J. Entomol. 105 (1): 41-44, 2008 | DOI: 10.14411/eje.2008.005 The honeybee (Apis mellifera L.) has a large number of geographic subspecies distributed across Europe, Africa and Asia, many of which have been described. This identification is important for bee breeding and preserving honeybee biodiversity. To investigate the origin of Jordanian honeybees, 32 samples collected from different locations in Jordan were analyzed using four different enzyme systems: Bg/II site in cytochrome oxidase b (Cytb), EcoRI site in large ribosomal (lsRNA) subunit, XbaI site in cytochrome c oxidase I (COI) subunit and HinCII site in cytochrome c oxidase I (COI) subunit. The first three enzymes were found to be polymorphic. The DNA banding pattern analyses revealed that Jordanian honeybees belong to the East Mediterranean and Middle Eastern mitochondrial lineages. |
Linkage analysis of the visible mutations Sel and Xan of Bombyx mori (Lepidoptera: Bombycidae) using SSR markersXuexia MIAO, Muwang LI, Fangyin DAI, Cheng LU, Marian R. GOLDSMITH, Yongping HUANGEur. J. Entomol. 104 (4): 647-652, 2007 | DOI: 10.14411/eje.2007.081 Wild type silkworm larvae have opaque white skin, whereas the mutants Sel (Sepialumazine) and Xan (Xanthous) are yellow-skinned. Previous genetic analysis indicated that Sel and Xan are on established linkage groups 24 (0.0) and 27 (0.0), respectively. However, in constructing a molecular linkage map using simple sequence repeat (SSR) loci, we found that the two mutations were linked. To confirm this finding, we developed a set of SSR markers and used them to score reciprocal backcross populations. Taking advantage of the lack of crossing-over in female silkworms, we found that the progeny of backcrosses between F1 females and males of the parental strains (BC1F) of the two visible mutations had the same inheritance patterns linked to the same SSR markers. This indicated that the two visible mutations belonged to the same chromosome. To confirm this finding, we tested for independent assortment by crossing Sel and Xan marker strains with each other to obtain F1 and F2 populations. Absence of the expected wild type class among 5000 F2 progeny indicated that the two visible mutations were located on the same linkage group. We carried out recombination analysis for each mutation by scoring 190 progeny of backcrosses between F1 males and parental females (BC1M) and constructed a linkage map for each strain. The results indicated that the Sel gene was 12 cM from SSR marker S2404, and the Xan gene was 7.03 cM from SSR marker S2407. To construct a combined SSR map and to avoid having to discriminate the two similar dominant mutations in heterozygotes, we carried out recombination analysis by scoring recessive wild type segregants of F2 populations for each mutation. The results showed that the Sel and Xan genes were 13 cM and 13.7 cM from the S2404 marker, respectively, consistent with the possibility that they are alleles of the same locus, which we provisionally assigned to SSR linkage group 24. We also used the F2 recessive populations to construct two linkage groups for the Sel and Xan genes. |
The development of sexual differences in body size in Odonata in relation to mating systemsMartin-Alejandro SERRANO-MENESES, Mónica AZPILICUETA-AMORÍN, Tamás SZÉKELY, Alex CÓRDOBA-AGUILAREur. J. Entomol. 104 (3): 453-458, 2007 | DOI: 10.14411/eje.2007.065 Adult body size is the result of important environmental, maternal and/or genetic effects acting on animals during development. Here we investigate how sexual size dimorphism (SSD) develops in seven species of Odonata: Anax imperator, Cordulegaster boltonii, Onychogomphus uncatus, Oxygastra curtisii (Anisoptera), Cercion lindeni, Ischnura graellsii and Platycnemis acutipennis (Zygoptera). SSD of both the last larval and adult stages of the same individuals, which were reared under laboratory conditions, was measured. The aims were to investigate (i) whether SSD develops during the larval stage, (ii) the direction of larval and adult SSD, and (iii) whether the direction of adult SSD can be predicted by the mating system of a given species (e.g. males of territorial species being larger than females and the opposite for non-territorial species). We found that although larval differences in size may be present between the sexes, these are not necessarily shown in the adult stage (they may change or disappear). Also, the mating system was not related to patterns of adult SSD. Differences in SSD in larvae may be caused by differential use of resources via differential niche-utilisation or sex-specific growth patterns. We highlight the fact that sexual selection favouring large male size and fecundity selection, which selects for large females may be acting on the observed patterns in SSD in adults. |
Review of larval morphology of beetles of the suborder Archostemata (Insecta: Coleoptera), including first-instar chaetotaxyVasily V. GREBENNIKOVEur. J. Entomol. 101 (2): 273-292, 2004 This paper presents a synthesis of morphological information on larvae of the beetle suborder Archostemata. Larvae of the following families and species were studied: Ommatidae: Omma sp.; Micromalthidae: Micromalthus debilis LeConte, 1878; Cupedidae: Priacma serrata LeConte, 1861, Distocupes varians (Lea, 1902), Rhipsideigma raffrayi (Fairmaire, 1884), Tenomerga cinerea (Say, 1831) and Tenomerga mucida (Chevrolat, 1829). Morphological characters of the suborder and three families are described. Monophyly of the suborder is strongly supported by more than 10 larval autapomorphies. A close relationship between Micromalthidae and Cupedidae is confirmed. New larval characters are introduced, including chaetotaxy of first instar larvae of Micromalthus LeConte, 1878, Priacma LeConte, 1874 and Distocupes Neboiss, 1984. An identification key to families and subfamilies of Archostematan larvae is provided, along with a checklist of extant Archostemata taxa. The work is illustrated with 120 morphological drawings. |
Experimental evidence for competitive exclusion of Myzus persicae nicotianae by Myzus persicae s.s. (Hemiptera: Aphididae) on sweet pepper, Capsicum annuum (Solanaceae)Daniel H. TAPIA, Alejandra J. TRONCOSO, Renzo R. VARGAS, Ruby OLIVARES-DONOSO, Hermann M. NIEMEYEREur. J. Entomol. 105 (4): 643-648, 2008 The importance of interspecific competition as a force promoting specialization in phytophagous insects has been long debated. Myzus persicae sensu stricto (Hemiptera: Aphididae) is one of the most polyphagous aphids. Its subspecies, M. persicae nicotianae, is found mainly on tobacco, although it can survive and reproduce on a relatively wide range of plant species in the laboratory. Since life history traits of these taxa make competitive interactions likely, we hypothesize that asymmetrical competition occurs between M. p. nicotianae and M. persicae s.s., and accounts for the exclusion of the former when they share a common resource. This hypothesis was tested in laboratory experiments, which examined the population growth of colonies of both taxa coexisting on sweet pepper. A replacement series experiment was set up with both aphid taxa on sweet pepper plants, and the rates of population growth (RPG) evaluated at 5 day intervals for 25 days. M. p. nicotianae showed a significantly lower RPG when interacting with M. persicae s.s. than when in monotypic colonies, while M. persicae s.s. RPG was unaffected by competition. The relative population growth from the second census onwards of M. persicae s.s. was consistently higher than that of M. p. nicotianae. Finally, the RPG of M. p. nicotianae was significantly reduced when the plant was infested with M. persicae s.s. The results suggest that the absence of M. p. nicotianae from sweet pepper in the field in Chile can be partly explained by competitive exclusion by M. persicae s.s. |
Dispersal dynamics: Distribution of lady beetles (Coleoptera: Coccinellidae)Vlastimil KŘIVANEur. 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: 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. |
The multicolored Asian ladybeetle Harmonia axyridis (Coleoptera: Coccinellidae) in Quebec agroecosystems ten years after its arrivalÉric LUCAS, Charles VINCENT, Geneviève LABRIE, Gérald CHOUINARD, François FOURNIER, Francine PELLETIER, Noubar J. BOSTANIAN, Daniel CODERRE, Marie-Pierre MIGNAULT, Pierre LAFONTAINEEur. J. Entomol. 104 (4): 737-743, 2007 | DOI: 10.14411/eje.2007.094 The multicolored Asian ladybeetle, Harmonia axyridis (Coleoptera: Coccinellidae), was first reported in southern Canada in 1994. In this study, we examined the status of the ladybeetle in Quebec agroecosystems seven to ten years after its arrival. We integrated the findings from eight independent field studies carried out in pome fruit, grapes, medicinal crops, field corn, sweet corn, sweet pepper, lettuce, and soybean. Nine aphidophagous and 6 coccidophagous coccinellid species were sampled on these crops. Among these aphidophagous species, three invasive (H. axyridis, Coccinella septempunctata and Propylea quatuordecimpunctata) as well as one indigenous species (Coleomegilla maculata lengi) were consistently present. Higher richness was observed in perennial crops, where the 6 coccidophagous coccinellids were almost exclusively present. Higher abundance of aphidophagous coccinellids was observed in field and sweet corn. The multicolored Asian ladybeetle was a dominant species of the coccinellid assemblage in all crops monitored. |



