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Identity, larva and distribution of the Oriental soldier fly, Odontomyia ochropa (Diptera: Stratiomyidae)Jana NERUDOVÁ-HORSÁKOVÁ, Damir KOVAC, Rudolf ROZKO©NÝEur. J. Entomol. 104 (1): 111-118, 2007 | DOI: 10.14411/eje.2007.017
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Impact of poor host-parasitoid synchronisation on the parasitism of Cameraria ohridella (Lepidoptera: Gracillariidae)Giselher GRABENWEGER, Hildegard HOPP, Barbara JÄCKEL, Hartmut BALDER, Tanja KOCH, Silke SCHMOLLINGEur. J. Entomol. 104 (1): 153-158, 2007 | DOI: 10.14411/eje.2007.022 Poor synchronisation is considered to be one important reason for the ineffective control of the invasive horse chestnut leafminer by native parasitic Hymenoptera. Parasitoids hibernating in dry horse chestnut leaves break diapause early in spring and presumably leave the vicinity, since no hosts are available when they emerge. As a consequence, the percentage parasitism of the first generation of the leafminer in early summer is low. The experiments presented below were designed to test this hypothesis. Horse chestnut saplings were brought on in a greenhouse and infested artificially with C. ohridella prior to parasitoid emergence in the field. These saplings were then exposed to parasitoid attack under natural conditions to eliminate the synchronisation problem. In addition, the parasitoid complexes of other leafmining hosts, which appear early in the season, were analysed. The results confirm that the most important parasitoids of the horse chestnut leafminer are active early in the season, long before the larvae of the first generation of the host are present. Nevertheless, poor synchronisation with the invasive host did not significantly influence the abundance of the most important parasitoid in the complex, Minotetrastichus frontalis, and consequently had no impact on the parasitism of C. ohridella. Nevertheless, a detailed analysis of the parasitoid community shows that certain species are affected by poor synchronisation, while others are probably limited by ecological parameters, such as a specialisation to foraging in particular strata of vegetation. Several leafmining flies were found early in spring infesting other host plants commonly planted in urban green areas, including species with a parasitoid complex similar to that of C. ohridella. The role of these alternative hosts in the food web associated with the horse chestnut leafminer should be subject to further study. |
Oviposition at low temperatures - late season negatively affects the leaf beetle Galeruca tanaceti (Coleoptera: Galerucinae) but not its specialised egg parasitoid Oomyzus galerucivorus (Hymenoptera: Eulophidae)Torsten MEINERS, Barbara RANDLKOFER, Elisabeth OBERMAIEREur. J. Entomol. 103 (4): 765-770, 2006 | DOI: 10.14411/eje.2006.103 Insects experience important selection pressures from their parasitoids, which affect both their population dynamics and their evolutionary responses. The interaction between the egg parasitoid Oomyzus galerucivorus Graham (Hymenoptera: Eulophidae) and its chrysomelid host Galeruca tanaceti L. (Coleoptera: Galerucinae) was investigated with the particular aim determining whether the chrysomelid host can escape its parasitoid by ovipositing late in the year as early as September. Although the leaf beetle and its parasitoid emerge in April, G. tanaceti starts to oviposit after spending the summer in reproductive diapause. The objective was to determine, whether the small parasitic wasp can parasitise its host's eggs even at the end of its host's reproductive season in December, when temperatures are low. Beetle oviposition, parasitism rates and temperatures were measured on three comparable mesoxerophytic grassland sites over the coarse of a season. Beetle oviposition, but not parasitism, was significantly positively dependent on temperature. Rate of oviposition decreased over the oviposition period with decrease in temperature. In contrast, after a lag phase of 1-2 weeks at the beginning of the oviposition period in September beetle egg clutches were parasitised at a constant rate until the end of the season in December. Host eggs were parasitised even at mean daily temperatures of 0-6°C. Thus the tansy leaf beetle does not escape from egg parasitism by ovipositing late in the season in central Germany. |
Cockroach tergal glands producing female sex attractant pheromones and male aphrodisiacs in particular in the subfamily Blaberinae (Blattaria: Blaberidae)Leam SRENGEur. J. Entomol. 103 (4): 817-829, 2006 | DOI: 10.14411/eje.2006.112 Two principal pheromones are essential in all cockroach sexual behavioral sequences: the volatile sex attractant pheromone released by one partner for long distance attraction and an aphrodisiac sex pheromone produced exclusively by male tergal glands for female mounting and feeding behavior. In the Blaberinae subfamily, the female produces volatile sex attractant pheromones and the male, aphrodisiacs. A close relationship is known to exist between the release of these pheromonal signals from specific glands and the corresponding behaviors (female calling posture and male wing raising). However, in this cockroach group, no data on the glands secreting sex attractant pheromones and aphrodisiacs have been available until now. In seven species of the Blaberinae subfamily: Blaberus colosseus, B. craniifer, B. discoidalis, Blaptica interior, Byrsotria fumigata, Eublaberus distanti and E. posticus; one species of the Zetoborinae subfamily: Schultesia lampyridiformis; one species of the Epilamprinae subfamily: Epilampra maya and one species of the Panesthiinae subfamily, Panesthia sp., the females possess all pygidial glands on the 10 th tergite and the males have tergal glands situated anteriorly, generally on tergites T1 and T2. These glands are formed of type 3 glandular units with two cells, i.e. glandular and canal cells. The uniform presence of female pygidial glands and male tergal glands explains their relationship with their corresponding sexual behaviors. |
Life history and reproductive behavior of the endemic Hawaiian Anomalochrysa hepatica (Neuroptera: Chrysopidae): A comparative approachMaurice J. TAUBER, Catherine A. TAUBER, Timothy W. HILTONEur. J. Entomol. 103 (2): 327-336, 2006 | DOI: 10.14411/eje.2006.043 Our study focuses on a series of biological characteristics that Anomalochrysa hepatica exhibits; herein, we compare these features with those expressed by two other species within the endemic Hawaiian lacewing genus. Some of the characteristics (No. 2-3, below) vary greatly among the three congeners and may be of phylogenetic importance; others (No. 1, below) probably are not. Our study showed the following: (1) Developmental response to temperature. Anomalochrysa hepatica's developmental rates under a range of temperatures parallel those of the congener A. maclachlani, but A. hepatica's thermal threshold is lower. It is possible that both species' developmental responses to temperature are subject to considerable geographic variation and thus are of little phylogenetic significance at the species level. (2) Larval color change. Third instars of A. hepatica undergo a striking color change as they mature. In expressing this trait, A. hepatica resembles its closely related congener, A. maclachlani, but differs from the more distantly related congener, A. frater. This color change may have phylogenetic importance. (3) Reproductive behavior. Courtship and mating in Anomalochrysa comprise a consistent sequence of behavioral elements, some of which differ among the three species. For example, during courtship, A. hepatica produces readily audible clicks that are associated with forward flicking of the forewings; in A. maclachlani, readily audible clicking occurs with simultaneous flicking of the fore- and hind wings; in A. frater wing-flicking is present but we did not perceive audible clicks. Some of the interspecific variation in mating behavior may also involve specific morphological modifications; aspects of both the behavioral and morphological variation may provide useful characters for phylogenetic study. (4) Oviposition and rates of egg survival in the field. Unlike other Chrysopidae, endemic Hawaiian Anomalochrysa, including A. hepatica, typically lay unstalked eggs; however, species vary in their patterns of egg laying. Both A. hepatica and A. maclachlani deposit clustered eggs, whereas A. frater lays eggs singly. In nature, the average rate of hatching per A. hepatica egg mass was ~75%. Several species of introduced predators and a species of trichogrammatid parasitoid attacked these eggs. |
Phytophagous insects of giant hogweed Heracleum mantegazzianum (Apiaceae) in invaded areas of Europe and in its native area of the CaucasusSteen Ole HANSEN, Jan HATTENDORF, Ruediger WITTENBERG, Sergey Ya. REZNIK, Charlotte NIELSEN, Hans Peter RAVN, Wolfgang NENTWIGEur. J. Entomol. 103 (2): 387-395, 2006 | DOI: 10.14411/eje.2006.052 Giant hogweed, Heracleum mantegazzianum (Apiaceae), was introduced from the Caucasus into Western Europe more than 150 years ago and later became an invasive weed which created major problems for European authorities. Phytophagous insects were collected in the native range of the giant hogweed (Caucasus) and were compared to those found on plants in the invaded parts of Europe. The list of herbivores was compiled from surveys of 27 localities in nine countries during two seasons. In addition, literature records for herbivores were analysed for a total of 16 Heracleum species. We recorded a total of 265 herbivorous insects on Heracleum species and we analysed them to describe the herbivore assemblages, locate vacant niches, and identify the most host-specific herbivores on H. mantegazzianum. When combining our investigations with similar studies of herbivores on other invasive weeds, all studies show a higher proportion of specialist herbivores in the native habitats compared to the invaded areas, supporting the "enemy release hypothesis" (ERH). When analysing the relative size of the niches (measured as plant organ biomass), we found less herbivore species per biomass on the stem and roots, and more on the leaves (Fig. 5). Most herbivores were polyphagous generalists, some were found to be oligophagous (feeding within the same family of host plants) and a few had only Heracleum species as host plants (monophagous). None were known to feed exclusively on H. mantegazzianum. The oligophagous herbivores were restricted to a few taxonomic groups, especially within the Hemiptera, and were particularly abundant on this weed. |
A comparison of three trapping methods used to survey forest-dwelling ColeopteraEsko HYVÄRINEN, Jari KOUKI, Petri MARTIKAINENEur. J. Entomol. 103 (2): 397-407, 2006 | DOI: 10.14411/eje.2006.054 Sampling of insect communities is very challenging and for reliable interpretation of results the effects of different sampling protocols and data processing on the results need to be fully understood. We compared three different commonly used methods for sampling forest beetles, freely hanging flight-intercept (window) traps (FWT), flight-intercept traps attached to trunks (TWT) and pitfall traps placed in the ground (PFT), in Scots pine dominated boreal forests in eastern Finland. Using altogether 960 traps, forming 576 sub-samples, at 24 study sites, 59760 beetles belonging to 814 species were collected over a period of a month. All of the material was identified to species, with the exception of a few species pairs, to obtain representative data for analyses. Four partly overlapping groups were used in the analyses: (1) all, (2) saproxylic, (3) rare and (4) red-listed species. In terms of the number of species collected TWTs were the most effective for all species groups and the rarer species the species group composed of (groups 1-2-3-4) the larger were the differences between the trap types. In particular, the TWTs caught most red-listed species. However, when sample sizes were standardized FWTs and TWTs caught similar number of species of all species groups. PFTs caught fewer species of all species groups, whether the sample sizes were standardized or not. In boreal forests they seem to be unsuitable for sampling saproxylic, rare and red-listed species. However, the PFTs clearly sampled different parts of species assemblages than the window traps and can be considered as a supplementary method. The abundance distribution of saproxylic species was truncated lognormal in TWT and pooled material, whereas unclassified material failed to reveal lognormal distribution in all the trap types and pooled material. The results show that even in boreal forests sample sizes of at least thousands, preferably tens of thousands of individuals, collected by a high number of traps are needed for community level studies. Relevant ecological classification of material is also very important for reliable comparisons. Differences in the performance of trap types should be considered when designing a study, and in particular when evaluating the results. |
Unusual host plant of Hoplitis pici, a bee with hooked bristles on its mouthparts (Hymenoptera: Megachilidae: Osmiini)Andreas MÜLLEREur. J. Entomol. 103 (2): 497-500, 2006 | DOI: 10.14411/eje.2006.064
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Berchmansus elegans (Neuroptera: Chrysopidae): Larval and adult characteristics and new tribal affiliationCatherine A. TAUBER, Maurice J. TAUBER, Gilberto S. ALBUQUERQUEEur. J. Entomol. 103 (1): 221-231, 2006 | DOI: 10.14411/eje.2006.024 The genus Berchmansus Navás, which was previously assigned to the tribe Leucochrysini, consists of three very rare species, all described from the Neotropics and all poorly known. Our report (1) provides the first description of a Berchmansus larva, the first instar of Berchmansus elegans (Guérin Méneville), (2) illustrates and redescribes the B. elegans adult, with emphasis on male and female genitalia, and (3) examines the larval and adult characters vis-à-vis the tribal affiliation of the genus. Given that the B. elegans adult and first instar share many apomorphies with other belonopterygine genera, this species belongs in the cosmopolitan tribe Belonopterygini, rather than the New World tribe Leucochrysini. Although Berchmansus larvae have not been collected in the field, we suspect that, like other belonopterygines, they are associated with ant nests. B. elegans exhibits a number of highly modified and unusual structures, some of which (#1 to #5) are not reported for any other chrysopids. Specifically: Males have (1) a unique, quadrate, dome-like hood above the gonarcus and (2) large, coiled parameres on the gonosaccus. First instars have (3) a greatly enlarged subapical seta on the flagellum, (4) a transverse row of long, hooked setae along the dorso-anterior margin of the pronotum, and (5) setose laterodorsal tubercles on the meso- and metathorax, with (6) multi-pronged, hooked setae. |
Habitat of pre-hibernating larvae of the endangered butterfly Euphydryas aurinia (Lepidoptera: Nymphalidae): What can be learned from vegetation composition and architecture?Martin KONVICKA, Vladimir HULA, Zdenek FRICEur. J. Entomol. 100 (3): 313-322, 2003 | DOI: 10.14411/eje.2003.050 Habitats of pre-hibernating gregarious larvae of the endangered Marsh Fritillary butterfly (Euphydryas aurinia) were studied in field in Western Bohemia, Czech Republic. The species inhabits moist seminatural meadows managed by light grazing and haymaking; the only local host plant is Succisa pratensis. The redundancy analyses of the vegetation composition (around 166 nest-bearing and 381 unoccupied host plants) showed that nest presence was positively associated with short cushion-forming grasses (esp. Nardus stricta). It was negatively associated with competitively superior tall grasses (e.g., Deschampsia caespitosa) and tall herbs. Comparison of Ellenberg's indicator values of vegetation in occupied vs. unoccupied plots revealed that the nests were more often found in drier, nitrogen-poorer and more acidic conditions than unoccupied plants. Multiple regressions of nest presence against architecture of the host plants (170 occupied, 1280 unoccupied) revealed that the nests were associated with densely clumped host plants, low to medium height of sward and mechanical disturbance. The patterns agree with our knowledge of the biology of the larvae: short sward (related to low nitrogen, humidity, and low pH) facilitates larval basking; high host density reduces the likelihood of starvation. Sod disturbance facilitates host plant germination. The conditions favourable for the nests were also favourable for the host plant, but the plants grew in broader range of conditions than that occupied by the nests. The abandoning of a site results into a situation when the conditions first become intolerable for the butterfly, and ultimately for the plant. Since grazing and mowing have a different impact on vegetation composition and architecture, we propose that the studied populations have persisted in a semi-dynamic state in the two modes of management. Conservation management should mimic the dynamics of traditional land use on the smaller scales of extant colonies. |
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. |
Geographical versus food plant differentiation in populations of Maculinea alcon (Lepidoptera: Lycaenidae) in Northern HungaryJudit BERECZKI, Katalin PECSENYE, Zoltán VARGAEur. J. Entomol. 103 (4): 725-732, 2006 | DOI: 10.14411/eje.2006.096 The taxonomic status of Alcon Blues in Central and Western Europe (conventionally: Maculinea alcon and M. rebeli) is confused. Some authors distinguish them as separate species within the M. alcon species group, while others consider them to be subspecies or simply ecological forms. Our aim was to study the geographical versus food plant pattern of genetic differentiation among several populations of these taxa in Northern Hungary. Imagines were collected from 11 localities between 2000 and 2003. M. alcon feeding on G. pneumonanthe from three subregions and on G. cruciata from two subregions were analysed. Enzyme polymorphism was analysed at 16 enzyme loci using polyacrylamide gel electrophoresis. In the analysis of the data, F-statistics were computed and the total genetic variation partitioned into within and between population components. Nei's genetic distances were calculated and a UPGMA dendrogram constructed on the basis of the distance matrix. Hierarchical F-statistics and AMOVA were computed to study the pattern of genetic differentiation among the samples. PCA analysis was also carried out using the allele frequencies of the samples. The results of all analyses indicated strong differentiation among the samples. A sizeable portion of this variation was detected among the samples/generations collected from the same population. The distribution of the between population variation did not exhibit a clear split between the two food plant groups. In addition, the FST values computed using a restricted data set suggested significant differentiation among the subregions. The results of AMOVA and PCA also indicated that the geographic pattern was more expressed in the between sample variation than the conventional taxonomic pattern. |
Seasonal wing dimorphism and life cycle of the mole cricket Gryllotalpa orientalis (Orthoptera: Gryllotalpidae)Chihiro ENDOEur. J. Entomol. 103 (4): 743-750, 2006 | DOI: 10.14411/eje.2006.098 Control of seasonal wing dimorphism in the oriental mole cricket Gryllotalpa orientalis Brumeister (1839) from a wetland habitat in western Japan is described. The long-winged (LW) morph appeared from mid-June to September, whereas the short-winged (SW) morph appeared from September to mid-June. Individuals overwintered in either the adult or juvenile stage. The seasonal shift in wing morphology was linked to the overwintering stage. Individuals that hatched in May became SW adults in September-October and then overwintered, whereas those that hatched in June and July overwintered as juveniles and became LW adults in June of the following year. The life cycle of both morphs was univoltine. Reproductive benefits and constraints of each wing morph of G. orientalis are compared. |
Mating competition and parentage assessment in Ptomascopus morio (Coleoptera: Silphidae): A case for resource defense polygynySeizi SUZUKI, Masahiro NAGANO, Norio KOBAYASHIEur. J. Entomol. 103 (4): 751-755, 2006 | DOI: 10.14411/eje.2006.099
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Pollen preference of the Chrysoperla species (Neuroptera: Chrysopidae) occurring in the crop environment in western FranceJohanna VILLENAVE, Bruno DEUTSCH, Thierry LODÉ, Elizabeth RAT-MORRISEur. J. Entomol. 103 (4): 771-777, 2006 | DOI: 10.14411/eje.2006.104 Two species of the Chrysoperla carnea complex: Ch. carnea sensu Henry and Ch. lucasina, occur in the crop environment in western France. Within the framework of a conservation biological control program for protected seed crops, the pollen consumption of these common green lacewings was investigated. The diverticulum contents of collected specimens were analysed to determine their food preference. Ch. carnea sensu Henry and Ch. lucasina are opportunistic feeders, which are attracted to large patches of flowering plants. The establishment of monitoring an attractive environment for these predators is discussed. |
Spatial variation in the incidence of a sexually transmitted parasite of the ladybird beetle Adalia bipunctata (Coleoptera: Coccinellidae)K. Mary WEBBERLEY, Matthew C. TINSLEY, John J. SLOGGETT, Michael E.N. MAJERUS, Gregory D.D. HURSTEur. J. Entomol. 103 (4): 793-797, 2006 | DOI: 10.14411/eje.2006.108 Whilst sexually transmitted pathogens and parasites are common on insects and other animals, the factors affecting their incidence are currently uncertain. In order to understand the factors important in determining the presence of sexually transmitted parasites, it would be helpful to have information on intraspecific variation in incidence, as the causes of this variation are likely to reflect the likely causes of the presence/absence of sexually transmitted parasites across species. We therefore mapped the incidence of the parasite Coccipolipus hippodamiae within Europe on its primary host, the ladybird Adalia bipunctata. We observed that C. hippodamiae was present widely in Central, Southern and Eastern Europe, but was absent from northerly and north-western populations. The cause of this pattern of incidence variation is discussed, with particular reference to the voltinism of the host. We also note that the distribution of C. hippodamiae on A. bipunctata is not congruent with that of another sexually transmitted parasite of this species, Hesperomyces virescens. |
Prevalence and association of the laboulbenialean fungus Hesperomyces virescens (Laboulbeniales: Laboulbeniaceae) on coccinellid hosts (Coleoptera: Coccinellidae) in Kentucky, USAJames D. HARWOOD, Carlo RICCI, Roberto ROMANI, Kevin M. PITZ, Alex WEIR, John J. OBRYCKIEur. J. Entomol. 103 (4): 799-804, 2006 | DOI: 10.14411/eje.2006.109 The laboulbenialean fungi occur throughout the world and are closely associated with a range of arthropods, including many coleopteran hosts. Throughout the summer of 2004, coccinellids were collected from a Bluegrass savanna woodland ecosystem, dominated by blue ash Fraxinus quadrangulata and Chinkapin Oak Quercus muehlenbergii, and the adults were examined for the presence of Hesperomyces virescens using binocular and scanning electron microscopy. Over 80% of adult Harmonia axyridis, a species previously reported as having a persistent association with the fungus, were infected. No significant differences were observed in incidence on male and female hosts, however, the distribution of fungus differed between sexes. Female H. axyridis had a greater percentage of infection on their elytron compared to other parts of their body whilst male infection was concentrated around their elytra, legs and abdomen. Although infection rates were significantly lower, we report, for the first time, the presence of this fungus on the hosts Cycloneda munda, Brachiacantha quadripunctata and Psyllobora vigintimaculata. This is the first study documenting the incidence of this insect-associated fungus with these native coccinellids of North America. In the samples collected from the Bluegrass savanna, two species (Coleomegilla maculata and Hyperaspis signata) were not infected by this fungus. |
Activity of endo-polygalacturonases in mirid bugs (Heteroptera: Miridae) and their inhibition by plant cell wall proteins (PGIPs)Francesca FRATI, Roberta GALLETTI, Giulia DE LORENZO, Gianandrea SALERNO, Eric CONTIEur. J. Entomol. 103 (3): 515-522, 2006 | DOI: 10.14411/eje.2006.067
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Diapause development and cold hardiness of Pectinophora gossypiella (Lepidoptera: Gelechiidae) larvae in GreeceOlga P. KALTSA, Panagiotis G. MILONAS, Matilda SAVOPOULOU-SOULTANIEur. J. Entomol. 103 (3): 541-545, 2006 | DOI: 10.14411/eje.2006.072 Larval diapause development and termination and some characteristics of cold hardiness in Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) were studied under field conditions in northern Greece. P. gossypiella overwintering larvae were sampled at 20 to 30 day intervals and subjected to two photoperiodic regimes at 20°C. In larvae kept under a long-day photoperiod (16L : 8D) diapause development was accelerated compared to those kept under a short-day photoperiod (8L : 16D). There was no difference in response to the two photoperiods after February. Mean number of days to pupation of P. gossypiella overwintering larvae decreased progressively through the sampling period, from November to April. Chilling is not a prerequisite but does accelerate diapause development. Supercooling points for P. gossypiella overwintering larvae ranged from -14 to -17°C with the majority dying after freezing. |
Effects of low temperatures on Chilocorus kuwanae (Coleoptera: Coccinellidae) trophic activityCarlo RICCI, Andrea PRIMAVERA, Valeria NEGRIEur. J. Entomol. 103 (3): 547-551, 2006 | DOI: 10.14411/eje.2006.074
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Phylogeny and evolutionary history of queen polymorphic Myrmecina ants (Hymenoptera: Formicidae)Florian M. STEINER, Birgit C. SCHLICK-STEINER, Heino KONRAD, Timothy A. LINKSVAYER, Swee-Peck QUEK, Erhard CHRISTIAN, Christian STAUFFER, Alfred BUSCHINGEREur. J. Entomol. 103 (3): 619-626, 2006 | DOI: 10.14411/eje.2006.083 The phylogenetic relationships in the myrmicine ant genus Myrmecina were analyzed using 1,281 bp of the mitochondrial cytochrome c oxidase I gene. Intermorphic queens observed in M. graminicola (Europe), M. nipponica (Japan), M. americana (North America; reported for the first time) and M. sp. A (Java) were reconstructed as an ancestral trait in this genus. Molecular-clock-based age estimates suggest that queen polymorphism evolved in Myrmecina at the latest during the Miocene. In terms of biogeographical regions, the inferred chronological order of divergence is: (oriental, (nearctic, (western palearctic, eastern palearctic))). |
Augmentation of managed populations of Osmia cornuta and O. rufa (Hymenoptera: Megachilidae) in Southeastern EuropeMiloje KRUNIĆ, Ljubiąa STANISAVLJEVIĆEur. J. Entomol. 103 (3): 695-697, 2006 | DOI: 10.14411/eje.2006.091 We describe augmentation of managed populations of Osmia cornuta and O. rufa in the vicinity of Belgrade (Serbia). Annual augmentation of O. cornuta populations was more than five-fold during the six years of our study. This was achieved by watering the soil near the Osmia augmentation shelters used for nest building. However, populations of O. rufa under the same treatment only doubled annually. Data are also presented on sex ratios in these managed populations, the sex ratio being an important factor in increasing population numbers and raising pollination efficacy. Sex ratio values (♂ : ♀) varied from 1.46 : 1 to 3.22 : 1 in the populations of O. cornuta and from 1.35 : 1 to 2.68 : 1 in those of O. rufa. |
Phoretic relationships between Uropodina (Acari: Mesostigmata) and centipedes (Chilopoda) as an example of evolutionary adaptation of mites to temporary microhabitatsJerzy BŁOSZYK, Joanna KLIMCZAK, Małgorzata LE¦NIEWSKAEur. J. Entomol. 103 (3): 699-707, 2006 | DOI: 10.14411/eje.2006.093 A survey of soil fauna in Poland revealed 30 cases of centipedes carrying mites of the sub-order Uropodina. The 155 phoretic deutonymphs collected belonged to two species of Uropodina - Oodinychus ovalis (C.L. Koch, 1839) and Uroobovella pulchella (Berlese, 1904). These mites displayed a high degree of selectivity in their choice of carrier. The only species of centipede transporting mites was Lithobius forficatus (Linnaeus, 1758), despite the presence of 30 other species in the same habitats. It is possible that the large size and relatively fast speed of movement of this centipede make it a very good mite carrier. The majority of the mites were located on the sides of the centipedes, on segments near the anterior end. The high selectivity in the choice of carrier as well as the point of attachment suggests adaptation by the mites for phoresy by L. forficatus. |
Preliminary phylogeny of Tribolium beetles (Coleoptera: Tenebrionidae) resolved by combined analysis of mitochondrial genesNevenka ME©TROVIĆ, Brankica MRAVINAC, Miroslav PLOHL, Đurđica UGARKOVIĆ, Branka BRUVO-MAĐARIĆEur. J. Entomol. 103 (3): 709-715, 2006 | DOI: 10.14411/eje.2006.094 The phylogenetic relationships of the three major species groups of Tribolium (Coleoptera: Tenebrionidae) were inferred using the simultaneous analysis of 642 bp of the most conserved part of mitochondrial DNA (mt DNA) cytochrome oxidase I (COI) and 448-452 bp of mt 16S rDNA. High sequence divergence was observed for both genes even among sibling species. The analysis of the combined segments of COI and 16S rDNA sequences produced a phylogenetic tree with moderate level of confidence. The tree topology showed monophyly of the genus Tribolium whose species were separated into three groups: "brevicornis" group (with T. brevicornis as the only representative), "castaneum" group (with T. castaneum, T. freemani, T. madens and T. audax) and "confusum" group (with T. confusum, T. anaphe and T. destructor). Sibling species pairs T. castaneum - T. freemani and T. madens - T. audax are clearly resolved. The preliminary results presented here give moderate support to the previously proposed phylogeny based on morphological data. |
Life-history variation in three coexisting species of carnid flies (Diptera: Carnidae), Carnus hemapterus, Hemeromyia anthracina and Hemeromyia longirostrisFrancisco VALERA, Manuel MARTÍN-VIVALDI, Miguel CARLES-TOLRÁEur. J. Entomol. 103 (2): 347-353, 2006 | DOI: 10.14411/eje.2006.045 Seasonal cycles constitute a major challenge for organisms since they may influence the genetic composition of a population, the species structure of a community and the interactions between organisms. Diapause is frequently used by insects to synchronize their life cycle with seasonal changes and is regarded as a key factor in the coexistence of competing species. Here the occurrence, abundance and emergence patterns of three poorly-known species of carnid flies (Carnus hemapterus Nitzsch, 1818, Hemeromyia anthracina Collin, 1949 and Hemeromyia longirostris Carles-Tolrá, 1992), which overwintered in the nests of several bird species at two localities, are reported and evidence of possible interspecific competition sought. Larvae of all three species were found in association with carrion and detritus. Both Hemeromyia species co-occurred in around 50% of the nests and Carnus with each of the Hemeromyia species at a lower rate (30-40% of the nests). Coexistence of all three carnid species was rare. We did not find any evidence of interspecific competition in the larval stage. Coexistence did not reduce the number of flies that emerged of any of the three species and the abundance of some species was even positively related. Species-specific emergence patterns and different habitat selection criteria (Carnus hemapterus seemed to avoid nests lined with vegetable material), which diminished the overlap between species were found. Such spatial and temporal segregation could facilitate the coexistence of these closely related species, which have similar ecological requirements, and might influence the seasonal dynamics of this poorly-known assemblage of insects inhabiting the nests of birds. |
Parasitoid complex and parasitism rates of the horse chestnut leafminer, Cameraria ohridella (Lepidoptera: Gracillariidae) in the Czech Republic, Slovakia and SloveniaLubomír VOLTER, Marc KENISEur. J. Entomol. 103 (2): 365-370, 2006 | DOI: 10.14411/eje.2006.049 The horse chestnut leaf miner, Cameraria ohridella Deschka & Dimić, is a species of unknown origin that recently invaded most of Europe, causing serious damage to horse chestnut trees, Aesculus hippocastanum. Parasitism was studied over a period of three years in the region of Plzeň in the Czech Republic. Additional collections were made in Slovakia and Slovenia. The parasitoid complex, dominated by polyphagous idiobiont parasitoids of the family Eulophidae, is similar to that found in other studies in Europe. Minotetrastichus frontalis (Nees) was the most abundant parasitoid found, except in Slovakia where Pediobius saulius (Walker) dominated. One parasitoid species, the eulophid Cirrospilus diallus (Walker) was recorded for the first time from C. ohridella. A new method is proposed to calculate stage-specific and total parasitism rates. Parasitism rates of spinning larvae and pupae were higher than of feeding larvae; however, total parasitism was low. We estimated that between 1% and 17% of moths died from parasitism during the larval and pupal stages whereas the rate of mortality caused by other factors varied from 7% to 62%, depending on the locality, year and generation. The proposed method for calculating total parasitism, based on the integration of stage-specific parasitism rates, which takes into account the mortality not directly attributed to parasitism, is discussed and compared with other methods commonly used in studies on C. ohridella. |
Morphological separation of Tomicus piniperda and T. destruens (Coleoptera: Curculionidae: Scolytinae): new and old charactersMassimo FACCOLIEur. J. Entomol. 103 (2): 433-442, 2006 | DOI: 10.14411/eje.2006.057
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More than one species of Messor harvester ants (Hymenoptera: Formicidae) in Central EuropeBirgit C. SCHLICK-STEINER, Florian M. STEINER, Heino KONRAD, Bálint MARKÓ, Sándor CSŐSZ, Gerhard HELLER, Beatrix FERENCZ, Botond SIPOS, Erhard CHRISTIAN, Christian STAUFFEREur. J. Entomol. 103 (2): 469-476, 2006 | DOI: 10.14411/eje.2006.060 It is commonly held that Central Europe harbours but a single harvester ant species, namely Messor structor. Recently discovered bionomic differences between two Central European populations, which may reflect interspecific variation, cast doubt on this assumption. In the present study we test alternative hypotheses - one versus two harvester ant species in Central Europe and adjacent regions - by investigating the genetic diversity of ants determined as M. structor or close to it ("M. cf. structor"). Sequences of the mitochondrial COI gene revealed two major lineages of different but partially overlapping geographic distributions, both occurring in Central Europe. The existence of a cryptic species within M. cf. structor is the most plausible interpretation, since the sequence divergence between the two major lineages equals those between M. capitatus, M. concolor and M. bouvieri. The phylogenetic analyses revealed a distinct substructuring for both of the detected major lineages and the possible existence of additional cryptic species. |
Adaptive preferential selection of female coccinellid hosts by the parasitoid wasp Dinocampus coccinellae (Hymenoptera: Braconidae)Dexter S. DAVIS, Sarah L. STEWART, Andrea MANICA, Michael E.N. MAJERUSEur. J. Entomol. 103 (1): 41-45, 2006 | DOI: 10.14411/eje.2006.006 Females of the parasitoid wasp Dinocampus coccinellae are known to parasitise both male and female coccinellid hosts. It is suggested that female hosts provide more resources for developing wasp larvae because they tend to be larger than male hosts, and female coccinellids have a much greater food intake than males. Thus the wasp's lifetime reproductive success should be increased by ovipositing preferentially in female rather than male hosts when given a choice. Laboratory experiments, using Coccinella septempunctata as a host, show that such a preference does exist. Wasps preferentially oviposit in females, and this preference is not simply a result of the larger mean size of females compared to males. These results corroborate higher rates of prevalence in female compared to male hosts reported previously. |
Effect of early succession in wildflower areas on bug assemblages (Insecta: Heteroptera)Thomas FRANK, Irene KÜNZLEEur. J. Entomol. 103 (1): 61-70, 2006 | DOI: 10.14411/eje.2006.011 One way of reducing the rapid decline in biological diversity in agricultural landscapes is to establish wildflower areas. The species richness and abundance of heteropteran bugs in twenty 1- to 4-year-old wildflower areas and winter wheat fields were compared, and the effects of succession in the wildflower areas investigated. Vegetation and environmental parameters (plant species richness, vegetation structure, flower abundance, field size, surrounding landscape) and their effects on bug species were explored. Total species richness and abundance of bugs were significantly lower in wheat fields than in wildflower areas but did not differ in the wildflower areas of different ages. The numbers of zoophagous bugs in the wildflower areas were positively correlated with the age of the wildflower areas. Correspondence analysis showed that the bug species composition in the winter wheat fields was very similar but strongly separated from that in the wildflower areas. The species composition of bugs in the wildflower areas became increasingly dissimilar with advancing successional age. In a partial canonical correspondence analysis, the bug assemblage was significantly associated with the number of perennial plant species, the number of annual plant species and vegetation structure, which accounted for 13.4%, 12.6% and 7.2% of the variance, respectively. As wildflower areas clearly increased heteropteran diversity on arable land and bug species composition changed with increasing successional stage, the establishment of a mosaic of wildflower areas of different age is recommended as it enables the survival of heteropteran bugs with different life history traits. |



