Mechanisms of the suppression of gonadotropic activity of the corpus allatum (CA) in macropterous females were compared with those previously reported for either diapause or starving non-diapause brachypterous females by reciprocal transplantations of the neuroendocrine complexes (comprising the brain-suboesophageal ganglion-corpora cardiaca-CA). The denervated CA stimulated reproduction in most females of all experimental groups suggesting an inhibition of the CA via nervous connections with the brain. The inhibition of the CA within the transplanted neuroendocrine complex was measured by the reproductive performance of feeding recipient females deprived of their own CA. The complex from starving non-diapause brachypterous females stimulated reproduction in 58.3-78.9% of recipients suggesting that the inhibition of the CA was mostly overcome by the stimulating internal milieu of feeding females. In contrast, the "macropterous" complex stimulated reproduction in only 18.8-37.5% of recipients, similar to the "diapause brachypterous" complex (32.0%). The results indicate that the "macropterism", similar to the diapause, is associated with a considerably lower responsiveness of the neuroendocrine complex to humoral stimulation by feeding compared to the responsivenes of the "starving" complex from brachypterous non-diapause females. On the other hand, the CA of macropterous females is of intermediate size between that of the feeding non-diapause and diapause brachypterous females, similar to the CA of the non-diapause brachypterous females deprived of food. Overall, the data suggest that the suppression of the CA activity results from a combination of the diapause-like refractoriness of the neuroendocrine complex with the starvation-like inhibition of the CA growth. Regulation of the CA activity is discussed in relation to the "oogenesis-flight syndrome" recorded for flying wing-polymorphic species of insects.

The blister beetle genus Teratolytta, belonging to the tribe Lyttini, is revised and a classification is proposed. Two main sections of the genus - one including five groups of species and the other three groups - are tentatively defined. Four new species from Eastern and Southern Anatolia are described (T. carlae sp. n., T. dvoraki sp. n., T. monticola sp. n., T. taurica sp. n.), and a key to the 17 recognized species is proposed. A diagnosis of the species as well as taxonomic remarks are proposed, and a catalogue of localities is presented. In particular, Teratolytta tricolor (Haag-Rutenberg, 1880) comb. n. is re-established as a distinct species, T. cooensis G. Müller, 1936 is confirmed as a synonym of T. gentilis (Frivaldszky, 1877), T. bytinskii Kaszab, 1957 as a synonym of T. senilis (Abeille de Perrin, 1895), and T. holzschuhi Dvořák, 1983 is proposed as a synonym of T. eylandti Semenow, 1894; some infraspecific forms are referred to the variability of T. gentilis and T. flavipes (Mulsant & Rey, 1858). The first instar larva of T. gentilis is described and figured, and the sexual behaviour of this species is also briefly studied.

The aphid alarm pheromone is known to trigger wing induction in pea aphids (Acyrthosiphon pisum). In reaction to alarm pheromone, aphids drop off the plant or walk away. While searching for a new feeding site they repeatedly encounter other members of the aphid colony and this increased contact rate is assumed to be important for wing induction ("pseudo-crowding" hypothesis). Because the encounter rate is a function of aphid colony size, wing induction in aphids in the presence of a predator should be a function of the number of aphids on the plant. We placed two, seven or 13 adult pea aphids on bean plants, and exposed the different-sized colonies to synthetic alarm pheromone to test the density-dependence of predator-induced wing induction. The mean percentage of winged morphs among the offspring produced on the plants ranged from 10 to 80 percent and increased both with aphid number and exposure to alarm pheromone. There was no synergy between aphid number and alarm pheromone exposure indicating that both factors are additive. The implications for aphid metapopulation dynamics are discussed.

The zoophytophagous mirid bug Macrolophus caliginosus is an important biocontrol agent of whiteflies in the Mediterranean region. Periods of low productivity in commercial breeding units and unsuccessful establishment in greenhouses prompted this study of mating behaviour. Here we describe copulation behaviour, the diel mating periodicity and post-copulatory refractory period. A natural plant substrate needs to be provided if one wants to observe the copulatory behaviour of M. caliginosus in the laboratory. There was no apparent directional orientation in the approach of the two sexes, instead males pursued females after "accidentally" contacting them. Males mounted females from above, very rapidly, and without any obvious courtship behaviour, and copulation duration was very consistent (286.33 ± 4.23 s, mean ± SE). Observations over a 24-h period showed that mating was most frequent in the 8-h scotophase and first half of the 16-h photophase than in the second half of the photophase. Mated females became strongly unreceptive to new male mounting attempts, shaking their abdomen and leaving the plant if harassed. To determine the duration of the post-mating refractory period mating receptivity of females that had mated 1 or 2 weeks earlier was compared with that of virgin females of similar age. Mated females remained unreceptive even 2 weeks after mating, whereas half of the virgin females of equivalent age mated. Mated females were more likely to abandon a plant than virgin females when harassed by a male. Most males remated a few minutes after mating for the first time. M. caliginosus is atypical among mirids in that females apparently mate only once.

Variation with altitude in the composition of dung beetle assemblages and species richness was measured by sampling in spring, summer and autumn, both manually and with pitfall traps at twelve localities in the western Rhodopes Mountains. Non-parametric estimates indicate that most of the regional species pool was collected, some 73% of all taxa previously recorded in the entire region. The rate of species richness decrease with altitude is around 11 species per km, with an evident altitudinal change in the incidence of two main dung beetle functional groups in which Aphodiinae species begin to dominate Rhodopes assemblages at around 1400-1500 m. Species richness of dung pats is dominated by Scarabaeinae in spite of the fact that the number of Aphodiinae species is highest at each locality. Thus, Aphodiinae species are the main contributors to both local and regional pool richness and to species turnover between localities. These characteristics are similar to those observed in the assemblages from another European mountain range, also located near the Mediterranean-Eurosiberian boundary, the Iberian Central System. These results suggest that eastern European dung beetle assemblages are similar in compositional turnover and species richness variation with altitude to that observed in western Europe and North America.

A serine protease gene was cloned from the bumblebee, Bombus ignitus. The B. ignitus serine protease (BiSP) gene spans 1702 bp and consists of four introns and five exons coding for 250 amino acid residues. Southern blot analysis of genomic DNA suggested that BiSP gene is a single copy gene. The cDNA encoding BiSP was expressed as a 28-kDa polypeptide in baculovirus-infected insect cells and the recombinant BiSP showed activity in a protease enzyme assay. BiSP was specifically expressed in the midgut of B. ignitus queens, males, and workers, suggesting that the BiSP is a gut enzyme involved in the digestion of dietary proteins.

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.

The fecundity of the pseudococcid predators Nephus includens (Boheman) and N. bisignatus (Kirsch) (Coleoptera: Coccinellidae), fed on Planococcus citri Risso (Hemiptera: Pseudococcidae), was studied at several constant temperatures (15, 20, 25, 30, 32.5 and 35°C). With additional data for the development of the immature stages, life-fecundity tables were constructed and some population parameters calculated. The average total fecundities of N. includens at the above temperatures were 49.2, 97.8, 162.8, 108.5, 87.4 and 31.1 eggs/female, and average longevities 99.5, 84.7, 69.5, 61.1, 49.6 and 30.1 days, respectively. The net reproductive rates (R_o) were 8.0, 32.2, 60.7, 32.6, 20.7 and 2.6 females/female, and the intrinsic rates of increase (r_m) 0.014, 0.041, 0.083, 0.086, 0.077 and 0.024 females/female/day, respectively. The average total fecundities of N. bisignatus at 15, 20, 25, 30 and 32.5 ^¿C were 54.7, 72.1, 96.9, 56.0 and 22.8 eggs/female, and average longevities 116.1, 108.7, 71.8, 68.8 and 43.7 days, respectively. The net reproductive rates (R_o) were 13.9, 26.4, 31.3, 15.2 and 3.6 females/female and the intrinsic rates of increase (r_m) were 0.017, 0.035, 0.060, 0.051 and 0.024 females/female/day, respectively. The survival of females at each temperature was fitted using a Weibull distribution [S_(t) = exp(-(t/b)^c)]. Furthermore two mathematical models [Enkegaard equation: F = (a+b+x).e^(c+d.x), Analytis equation: F = a.(x-x_min)ⁿ .(x_min- x)^m] were fitted to the fecundity data.

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

The number of species of migratory Lepidoptera (moths and butterflies) reported each year at a site in the south of the UK has been rising steadily. This number is very strongly linked to rising temperatures in SW Europe. It is anticipated that further climate warming within Europe will increase the numbers of migratory Lepidoptera reaching the UK and the consequences of this invasion need urgent attention.

Using the fluorescent differential display technique, a special band named Bm541 was identified by screening for differentially expressed genes in the resistant silkworm strain Qiufeng, the susceptible strain Huaba35, and the near isogenic line BC₆, which carries the resistant gene to Bombyx mori densonucleosis virus (BmDNV). After applying the 5'RACE technique with specially designed primers, a 1148 bp cDNA clone containing a 387 bp open reading frame (ORF) was obtained. This gene was registered in GenBank under the accession number AY860950. The deduced amino acid sequence showed a 73.1% identity to the protein kinase C inhibitor (PKCI) of Drosophila pseudoobscura. In the deduced sequence of BmPKCI, the histidine triad (HIT) motif, which is essential for PKCI function, and the α-helix region, which is conserved among the PKCI family, were present. The data from quantitative real-time PCR (QRT-PCR) suggest that the expression levels of bmpkci in BC₆ and Qiufeng both with BmDNV-Z are significantly higher than those in Huaba35, which indicate that BmPKCI plays a role in resistance to BmDNV-Z.

Adults of some coccinellid species overwinter in aggregations consisting of many individuals. They may clump because adults are attracted to particular environmental stimuli and/or of an innate tendency to join conspecific individuals. Aggregation behaviour was studied in Coccinella septempunctata L., which forms small clumps, and Ceratomegilla undecimnotata (Schneider) and Hippodamia variegata (Goeze), which form large clumps. Adults were recorded at five hilltop hibernacula (400-1500 m altitude) in central Europe (50-51°N, 14-16°E) for periods up to 27 years. The hibernacula occur in areas sparsely covered with isolated grass tussocks or completely with stones. Numbers of adults recorded under each of 300-900 stones or among the stems of the grass tussocks were counted every year at each hibernaculum. The degree of aggregation was determined using Taylor's power law. The coccinellid distributions became more aggregated and the size of the aggregations increased as their abundance increased, less in C. septempunctata than in the other two species. Aggregations formed even in the absence of prominent structures, which may attract immigrants, and even when unoccupied stones or tussocks suitable for overwintering were available. Aggregations may be established and their size limited by the strength of the intrinsic preference to join conspecifics. The supposed advantage of aggregated overwintering must be greater than the risk associated with the easy spread of diseases.

The availability and quality of nectar for adults are thought to affect fecundity of the cotton bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). Experiments were conducted to analyze the effect of adult feeding on the fecundity, and oviposition pattern of moths, and larval performance (egg hatch). The moths were fed either on distilled water, honey solution, or one of a range of concentrations of sucrose solution. The results showed that diets with sugars significantly increased fecundity and adult lifespan. Lifespan, total numbers of eggs and egg mass were significantly higher for females that fed on sugar during adult life. Egg hatch (a measure of offspring fitness) decreased over time regardless of sucrose concentration, but had always higher levels in the groups fed sugars. The peak of the ovipositing period was delayed and prolonged, with more eggs deposited, when moths were fed on sugar solution. In conclusion, adult feeding increases the fecundity of female moths and plays an important role in enhancing the fitness of individual cotton bollworm offspring.

Dolichopodidae (over 6000 described species in more than 200 genera) is one of the most speciose families of Diptera. Males of many dolichopodid species, including Dolichopus, feature conspicuous ornaments (Male Secondary Sexual Characters) that are used during courtship. Next to these MSSCs, every identification key to Dolichopus primarily uses colour characters (postocular bristles; femora) of unknown phylogenetic relevance. The phylogeny of Dolichopodidae has rarely been investigated, especially at the species level, and molecular data were hardly ever involved. We inferred phylogenetic relationships among 45 species (57 samples) of the subfamily Dolichopodinae on the basis of 32 morphological and 1415 nucleotide characters (810 for COI, 605 for Cyt-b). The monophyly of Dolichopus and Gymnopternus as well as the separate systematic position of Ethiromyia chalybea were supported in all analyses, confirming recent findings by other authors based purely on morphology. Within Dolichopus, stable species groups could be assigned to four distinct categories on the basis of their statistical support in 7 phylogenetic analyses: (i) clades significantly supported in all analyses, (ii) clades supported in trees based on DNA and combined data, but only partly in morphological trees, (iii) clades significantly supported in trees based on DNA and combined data, but not in morphological trees, and (iv) clades consistently supported only in morphological trees. The phylogeny generated here provides a better understanding of the phylogenetic relevance of some debated morphological characters used for species and species-group characterizations in the most commonly used identification keys. In this respect, postocular bristle colour proved of little phylogenetic relevance since every group with species featuring black bristles also included species with partly yellow bristles. Entirely or partly infuscated femora explained the nodes of three stable species groups and even revealed an incorrect polarity of this morphological character in three species. Four of 6 complex MSSCs and 5 of 8 more common MSSCs were found consistently in further species groups.

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.

In the present study we tested whether the walking activity of macropterous females of the flightless wing-polymorphic bug Pyrrhocoris apterus (L.) can be stimulated by its native adipokinetic hormone Peram-CAH-II and the crustacean red pigment-concentrating hormone (Panbo-RPCH), and the effectiveness of the latter hormone in a lipid mobilization assay. Two different doses (10 or 40 pmol) of Peram-CAH-II or Panbo-RCPH were injected into 10-day-old macropterous females of P. apterus to evaluate their effects on the walking activity of treated females. The results obtained showed a significant stimulation of walking activity only with the lower dose (10 pmol) of either hormone Peram-CAH-II or Panbo-RPCH. On the contrary, the walking activity of the same-aged females of macropterous morph treated with the higher dose (40 pmol) of these hormones was decreased. The energy substrates mobilized in Panbo-RPCH-treated macropterous females were lipids. The question of whether the stimulation of locomotion by Panbo-RPCH is limited only to P. apterus or if it might also represent an important function of this hormone in other insects or even in crustaceans is discussed.

The aim of this study was to evaluate the effects of different diets on the development and reproduction of Lygus rugulipennis Poppius (Heteroptera: Miridae). Using 2 laboratory generations (F1 and F2) obtained from field-collected L. rugulipennis, the following diets were tested: beans, beans plus Tenebrio molitor (L.) (Coleoptera: Tenebrionidae) pupae, and a commercial artificial diet, which was developed for mass rearing of Lygus hesperus Knight. As oviposition substrates, beans and agar/parafilm rolls were used. Our data show that both the artificial diet and the artificial oviposition substrate were ineffective substitutes for beans for both laboratory generations. Stage-dependent and total survival rates clearly indicated that F1 Lygus bugs survive significantly longer when they are reared on vegetable substrates i.e., beans and beans plus pupae. The differential effects of the diets were more pronounced in the F2 generation, in which the embryonic development was longer for eggs from females reared on the artificial diet than on beans, and in which the second instar nymphs did not survive on the artificial diet. Both the total duration of post-embryonic development and the longevity of F1 males were shorter on the artificial diet than on beans. Female fecundity was affected by diet in terms of total duration of the oviposition period and mean number of eggs laid/female, since these parameters were lower on the artificial substrate, compared with those obtained on the bean substrate. However, the diet did not affect the morphological parameters, as there were no significant variations in weight, width of cephalic capsule, and tibia and hemelytra length. Since L. rugulipennis cannot be reared on the commercially available artificial diet, we discuss the necessity to improve both the artificial diet and oviposition substrate so that this Lygus bug and its specific egg parasitod Anaphes fuscipennis Haliday (Hymenoptera: Mymaridae) can be mass reared.

Insect genital characters are extensively used in species level taxonomy, and their value in species delimitation is great. Based on the lock-and-key hypothesis and that genital differences function as a mechanical isolation system between species, the value of genital characters has been thought to be superior to non-genital characters. Although geographical and other kind of intraspecific variation of genitalia is often assumed very moderate, its real extent is insufficiently investigated. We examined patterns of morphological variation in the male genitalia of the tortricid moth Pammene luedersiana, using geometric morphometric tools including thin-plate spline deformation grids, and found significant variation. This variation is continuous both within and between populations. No systematic shape variation was observed between populations, but genital size showed some geographic variability. The results suggest that genital morphology is not constant and should therefore be used with caution in lepidopteran taxonomy.

We describe the male courtship song of the newly-discovered species Drosophila santomea, endemic to the island of Saõ Tomé and the sister species of the widely distributed D. yakuba, which also inhabits the island. The song of D. santomea resembles that of D. yakuba in lacking a "sine" song, but the interpulse interval (IPI) in the "pulse" song is about 67 ms for the former species and 110 ms for the latter. This is the largest difference in IPI observed between any two sister species in the D. melanogaster subgroup, and may play a role in the strong sexual isolation between these two species.

The responses of females of the water strider, Aquarius paludum, to changes in NaCl concentration were examined in the laboratory. The insects were sampled seasonally in 2002 and 2003 at two reservoirs in Kochi, Japan, connected by a waterway, one at the mouth of the river with high NaCl concentrations (the range in NaCl concentration during a year: 0.1-1.08%) and one 700 m upstream, where the salinity was lower (0.03-0.23%). Sudden increase in NaCl concentration, from 0.45 to 0.9%, after adult strider emergence suppressed reproduction and promoted flight activity, whereas a decrease in salinity did not affect either trait. In the field, A. paludum was univoltine in brackish and multivoltine in freshwater ponds. Thus, the number of breeding periods per year was limited by fluctuations in the NaCl concentration in brackish habitats. Our results suggest that A. paludum can breed in brackish waters when the NaCl concentration is below the limitation for reproduction and growth. Abrupt increases in NaCl concentration caused by seawater surges, such as those following typhoons, can trigger the migration of individuals, which move to areas of lower NaCl concentration and so mix the genes of individuals inhabiting brackish and freshwater bodies.

The influence of olfactory and visual stimuli on the mating behaviour of Theresimima ampellophaga males was investigated in the field. A female model attached to a pheromone source significantly increased the number of males contacting and showing copulatory responses compared to their reaction to a pheromone stimulus alone. The pheromone stimulus was the primary factor releasing male copulatory behaviour, independent of the spatial arrangement of olfactory and visual cues. The role of the visual cues decreased with increasing distance between visual and olfactory cues. The reaction of males to pairs of models with different characteristics of conspecific females, in combination with a pheromone source placed 2 cm upwind from the center of the line between each pair of models, was compared. The size and shape of the female seemed not to be important, while the colour, posture, sex and species belongings significantly influenced the male's mating reaction.

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.

The rose aphid, Macrosiphum rosae, living on rose var. Black Magic, was reared in the laboratory at four constant temperatures 15, 18, 22 and 25 ± 1°C, 75 ± 5% R.H. and 14L : 10D. Parameters investigated included developmental rate, survival, pre-reproductive delay and fecundity. The rate of nymphal development (0.17) was greatest at 22°C. The longest developmental time (12.33 days) was recorded at 15°C. The generation time was longest and shortest at 15°C and 22°C respectively. The lower developmental threshold was calculated to be 9.05°C. Based on this, the degree-day requirement from birth to adulthood was found to be 77.5 dd. The pre-reproductive delay also decreased markedly with increase in temperature from 15°C to 22°C. The longest lifespan of apterous females (12.38 d) was observed at 15°C, whereas the shortest (8.06 d) was at 25°C. The mean adult longevity declined with increase in temperature from 15°C to 25°C. The fecundity of females (progeny/female) increased from 11.38 to 28.88 with increase in temperature from 15°C to 22°C but then decreased to 8.38 as the temperature increased from 22°C to 25°C. The largest (0.311) and smallest (0.113) r_m occurred at 22°C and 15°C respectively. All of the parameters of the M. rosae life cycle at the four temperatures tested were optimum at 22°C. This Iranian population of M. rosae can develop at lower temperatures than an Australian population.

The oviposition deterring effects of fresh larval tracks of Cheilomenes sexmaculata (F.), Ceratomegilla undecimnotata (Schneider), Cycloneda limbifer Casey, and Harmonia dimidiata (F.) on C. sexmaculata females were compared in standard laboratory choice tests. Moreover, the persistence of intraspecific effects of C. sexmaculata larval tracks were investigated. Fresh tracks of C. sexmaculata, C. limbifer and C. undecimnotata larvae effectively deterred C. sexmaculata females from ovipositing. The effect of fresh larval tracks of H. dimidiata was not statistically significant. The oviposition-deterring effects of 10 d-old conspecific larval tracks were considerably lower than those of fresh tracks, but remained significant. Clutch sizes were smaller in the blank test without larval tracks than in choice tests with fresh tracks of conspecific, C. limbifer, C. undecimnotata, H. dimidiata larvae and with 10 d-old tracks of conspecific larvae. The study indicates that semiochemicals in the tracks of conspecific and heterospecific coccinellid larvae can contribute considerably to the spacing of C. sexmaculata offspring among prey resources of differing quality and that conspecific as well as heterospecific larval tracks can influence clutch size.

Many aphidophagous coccinellids harbour male-killing bacteria. These maternally inherited bacteria kill males early in embryogenesis, female offspring of infected mothers gaining a large resource advantage from the consumption of their dead brothers. In this paper, the diversity of male-killing bacteria and their coccinellid hosts will be briefly reviewed. Thereafter, the impact that invasion by male-killers has on coccinellid hosts will be addressed in two ways. First, the selective effects due to the loss of male progeny, and the intra-genomic conflict resulting from the cytoplasmic inheritance of the bacteria will be considered. Reductions in mitochondrial diversity, effects on clutch sizes and the evolution of male-killer suppresser systems will be discussed. Second, the impact of female biased population sex ratios on the evolution of reproductive strategies and the primary sex ratio will be investigated. Preliminary results suggesting changes in male investment per copulation, reductions in female testing behaviour of males, and male biases in the progenic sex ratios of some uninfected male lines will be presented. Avenues for future work will be outlined.

The brassica leaf beetle, Phaedon brassicae Baly (Coleoptera: Chrysomelidae), one of the pests infesting cruciferous vegetables in China and Japan, is a multivoltine species that oversummers and overwinters as an adult. The effects of both temperature and photoperiod on reproductive diapause induction were systematically investigated in this beetle. Under 16L : 8D, most of the beetles entered reproductive diapause at 12-30°C, indicating that photoperiod played a crucial role in estivation diapause induction. Under 12L : 12D, all adults developed without diapause at 28 and 30°C; less than 25% of the individuals entered reproductive diapause at 16-24°C; however, 46.1% of the individuals entered diapause at 12°C, suggesting that low temperature also had a relatively important influence on the determination of diapause. The photoperiodic response curves indicate that this species is a typical short-day species. The critical day-lengths at 20, 24 and 28°C were 13.2, 13.6 and 13.8 h, respectively. Transferring them from 16L : 8D to 12L : 12D or vice versa at different ages and/or stages during their development revealed that the photoperiod experienced by adults during the first 11 days might be important for diapause determination, even though an effect of photoperiod on the larval and pupal stages can not be excluded. Transferring individuals kept at a photoperiod of 12L : 12D from 25°C to 12°C or vice versa at different ages and/or stages during their development revealed that the temperature cue for diapause is mainly perceived by the late instar larvae and pupae.

Ecological studies on the buprestid beetle Capnodis tenebrionis (Linnaeus, 1767) were carried out in the laboratory and the field. In particular, attention focussed on the effects of seven different temperatures at different times during the day on the movement and feeding activity of this beetle. Field experiments in an apricot orchard recorded the flight activity of C. tenebrionis, with particular reference to the effect of temperature and wind. The experiments highlighted the marked response of movement, feeding and flight activity to increase in temperature. The optimal temperature for feeding, movement and flight was 30°C and above with negative effects occurring at 45°C. Flight generally occurred in the middle of the day. Wind had a negative effect on flight activity. Wind speeds in excess of 4 m/s prevented the insect from taking off. The spread of this phytophagous beetle from one orchard to another is unquestionably influenced by the daily activity and flight behaviour of the adult.

The whiteflies Trialeurodes lauri and T. ricini have been found to be moving in international plant trade. The taxonomic validity and separation of these species is relevant to the plant health quarantine services of the European Union as T. lauri is oligophagous, nor recorded as a virus vector and present in the EU, whereas T. ricini is polyphagous, reported to be a virus vector, and absent from the EU (except for the Canary Islands). Yet doubt has been cast on the validity of the two species, with the suggestion that T. lauri is merely a variant of T. ricini. The taxonomic relationship was therefore investigated using morphological and molecular data. One morphological character traditionally used for the separation of these two species, the arrangement of the submarginal papillae, was found to be unreliable but morphological differences between the two species were found in the cephalic setal state, body outline and dorsal pigmentation. However, the differences were subtle and not always reliable. The molecular data, based on the sequence of a fragment of the COI gene, support the hypothesis that T. ricini and T. lauri are distinct valid species.

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.

Eurytoma robusta Mayr (Chalcidoidea) exploits host galls either as a primary or secondary parasitoid, an entomophytophagous inquiline or occasionally even as a predator. We present data on its ecology and impact on gall densities and population trends of the gall fly Urophora cardui (L.) on Cirsium arvense (L.) Scop. Habitat preference, host gall selection, clutch size, and high incidence of superparasitism causing empty gall cells show that E. robusta, a generalist with a broad host spectrum, is relatively poorly adapted to parasitising U. cardui. The influence of E. robusta on U. cardui in the Belfort-Sundgau region (1970-2004), in the Upper Rhine Valley (1973-2004) and in north-eastern Bavaria (1977-2004), differed considerably. In the forests of the Upper Rhine Valley and the Belfort-Sundgau region, where U. cardui has relatively stable source-sink populations, E. robusta is present but not the dominant mortality factor of the gall fly. In most areas of north-eastern Bavaria U. cardui occurs in fragmented populations and short lived non-equilibrium metapopulations. In these systems E. robusta became more abundant over the last five years, which resulted in a high incidence of superparasitism, an increase in the number of empty gall cells and reduced gall quality. The greatly increased degree of parasitism and an excess of empty cells resulted recently in the collapse of most local populations of U. cardui in the study area south of Bayreuth (north-eastern Bavaria). Together with earlier records the data presented here suggest that in north-eastern Bavaria E. robusta cause fluctuations in the abundance of U. cardui, which have a periodicity of 5-7 years. A remarkable feature of the oligophagous E. robusta is its high fidelity to formerly abundant U. cardui populations, which, with declining host densities, leads to overexploitation, resulting in a high incidence of superparasitism and high larval mortality. The possible influence of the habitat structure on the effect of E. robusta on the population dynamics of U. cardui is discussed. Our data plus that of other authors suggest that, with regard to U. cardui, E. robusta can develop a temporary local host specialisation.