A variety of plant protection products and other agrochemicals are used in agro-ecosystems. Products approved for integrated pest management (IPM) or organic farming should have minimal negative side effects on beneficial insects. The Asian harlequin ladybird Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) has become a widespread and important generalist predator of certain agricultural pests, mainly aphids, throughout Europe. We studied the effects of two agrochemicals, Boundary SW^® (auxiliary plant protection product) and Prev B2^® (foliar boron fertilizer), usually regarded as "environmentally friendly" and known to have insecticidal side effects against some fruit and vegetable pests (e.g., aphids, spider mites, weevils), on the last larval instar and adults of Harmonia axyridis. The conventional organophosphate insecticide Reldan 22^® was used as a chemical standard for evaluating the lethal effect, because this product is usually effective against a broad spectrum of insects, and indeed was immediately lethal for both the adults and larvae of this species. However, whereas Prev B2^® had no effect, adult ladybirds sprayed with Boundary SW^® survived only for up to 25 h and also none of the larvae completed their development. Thus, although our experiments were not made under natural conditions, the use of Boundary SW^® cannot be recommended for IPM and organic farming in terms of safeguarding insect predators such as Harmonia axyridis until further more detailed testing.

The water-hyacinth grasshopper, Cornops aquaticum, occurs in freshwater environments in the New World between latitudes 23°N and 35°S. At the southernmost margin of this distribution the populations are polymorphic for three centric fusions (Robertsonian translocations). The frequencies of these chromosome rearrangements increase southwards and the recombination in structural homozygotes and heterozygotes diminishes both along the middle and lower courses of the Paraná River. In the present paper we report a similar cline along the southward flowing Uruguay River. In addition, we report the morphological effects of two of these centric fusion polymorphisms, namely the fusions between chromosomes 2 and 5 of the standard complement (fusion 2/5) and chromosomes 3 and 4 (fusion 3/4) and extend this study to the Uruguay River. There is a strong inverse correlation of fusion frequency with temperature, which indicates that these polymorphisms may be related to increased tolerance of colder climates in this originally tropical species, or some other correlated variable. This study is a further example of chromosomal clines correlated with latitude and is one of a few examples of chromosome polymorphisms associated with phenotypic effects. Finally, it indicates ways of using this species for controlling pests.

Hubble D. 2017: Leaf Beetles. Ecology and Identification. Naturalists' Handbook 34. Pelagic Publishing, Exeter, 149 pp. ISBN 978-1-78427-150-3. Price GBP 19.99.

Cannibalism, the act of eating an individual of the same species has been little studied in omnivorous insect predators. Dicyphus errans (Wolff) (Hemiptera: Miridae) is a generalist omnivorous predator that commonly occurs in tomato greenhouses and field crops in the Mediterranean basin. In this work cannibalism among same-aged neonate nymphs of D. errans was studied when 1, 2, 4, 8 or 16 individuals were placed in a Petri dish along with or without heterospecific prey. Although nymphs were unable to complete their development in the absence of prey they survived longer when there were initially 2 individuals per dish than in any other treatment including a single individual. This may indicate that cannibalism in this predator has positive effect on nymphal survival, which however was not the case at higher densities. The presence of heterospecific prey increased nymphal survival and individuals were as equally successful in completing their development as when kept singly. Developmental time in all the treatments was very similar. Adult weight of both females and males was significantly greater when a nymph was reared alone and similar in all the other treatments. The results indicate that cannibalism occurs among neonates of D. errans if heterospecific prey is scarce and has a negative effect on adult weight when heterospecific prey is abundant. This should be considered in studies on enhancing the biocontrol efficiency or mass rearing of this predator.

Life table data of natural enemies are often used to understand their population dynamics and estimate their potential role in the biological control of pests. Macrosiphum euphorbiae (Thomas) (Hemiptera: Aphididae) is an important pest of several crops and its intrinsic rate of population increase (r_m) is 0.282 at 22°C. The life table parameters (immature mortality, developmental time, sex ratio of emerging adults, fecundity and longevity) of Praon volucre (Haliday) (Hymenoptera: Braconidae: Aphidiinae) parasitizing M. euphorbiae were estimated in a climatic chamber at 22 ± 1°C, RH 70 ± 10% and 12 h photophase. Immature mortality was 8.2%, developmental time of males and females was 13.9 and 14.4 days, respectively, and the sex ratio was 0.55 (= fraction of females). Parasitoid fecundity was 504 eggs and longevity 11 days. The net rate of reproduction (R₀) was 207.5 females and the intrinsic rate of population increase (r_m) 0.281 females/female/day. The time for doubling the population (TD) was 2.45 weeks. P. volucre has a population growth rate similar to that of its host M. euphorbiae and might therefore be a good candidate for the biological control of this aphid.

The expansion of urban areas is one of the most significant anthropogenic impacts on the natural landscape. Due to their sensitivity to stressors in both aquatic and terrestrial habitats, dragonflies and damselflies (the Odonata) may provide insights into the effects of urbanisation on biodiversity. However, while knowledge about the impacts of urbanisation on odonates is growing, there has not been a comprehensive review of this body of literature until now. This is the first systematic literature review conducted to evaluate both the quantity and topics of research conducted on odonates in urban ecosystems. From this research, 79 peer-reviewed papers were identified, the vast majority (89.87%) of which related to studies of changing patterns of biodiversity in urban odonate communities. From the papers regarding biodiversity changes, 31 were performed in an urban-rural gradient and 21 of these reported lower diversity towards built up city cores. Twelve of the cases of biodiversity loss were directly related to the concentrations of pollutants in the water. Other studies found higher concentrations of pollutants in odonates from built-up catchments and suggested that odonates such as Aeshna juncea and Platycnemis pennipes may be candidate indicators for particular contaminants. We conclude by identifying current research needs, which include the need for more studies regarding behavioural ecology and life-history traits in response to urbanisation, and a need to investigate the mechanisms behind diversity trends beyond pollution.

The mitochondrial genome of Saccharosydne procerus (Matsumura) is the first sequenced in the tribe Saccharosydnini (Hemiptera: Delphacidae: Delphacinae). In addition, the mitogenome sequence of Sogatella vibix (Haupt) (in Delphacini) is also sequenced. The Sa. procerus mitochondrial genome is 16,031 bp (GenBank accession no. MG515237) in length, and So. vibix is 16,554 bp (GenBank accession no. MG515238). The existence of purifying selection was indicated by the rate of nonsynonymous and synonymous substitutions. Three species of Delphacini, Laodelphax striatellus (Fallén), Sogatella furcifera (Horváth) and Nilaparvata lugens (Stål), are important pests of rice. The phylogeny of these three rice planthoppers based on the mitochondrial genome sequence was (L. striatellus + (So. vibix + So. furcifera)) + (N. muiri + N. lugens).

Drought tolerance of juvenile and adult life stages is relatively well understood, but very little is known about the tolerance of eggs to drought in this group of animals. The aim of the present study was therefore to investigate the water relations and drought sensitivity of eggs of the hygrophilic springtail, Folsomia candida Willem, 1902 (Isotomidae), exposed to a range of soil water potentials above and below the permanent wilting point of plants (-1.5 MPa). Under saturated conditions, eggs absorbed water during development and increased water content from 1.1 to 2.9 mg mg^-1 dry weight. By increasing drought conditions, water absorption was gradually reduced and was nullified approximately at the soil water potential equivalent to the osmolality of egg fluids (630 mOsm corresponding to -1.53 MPa). Eggs had a lower permeability for water (68 ± 13 µg water cm^-2 h^-1 mm Hg^-1) than adults (about 400 µg water cm^-2 h^-1 mm Hg^-1), but eggs were much more sensitive to drought than adults. Eggs did not survive exposure to -1.5 MPa, whereas adults readily survive this level of drought by absorbing water vapour. In conclusion, eggs of F. candida are sensitive to drought and would perish if soil water potential in the field approaches the wilting point of plants, which is often reached during summer droughts. The persistence of this species depends on the survival of post-embryonic life stages.

The Trophic Cascade Theory has been used to explain the organization of herbivorous insect communities in tropical ecosystems. In addition, the insect community associated with a species of plant can also be determined by the geographical distribution and taxonomic isolation of the plant. In this study, the following predictions about the number of herbivores associated with particular host plants were tested: (i) plant species belonging to large taxonomic groups with broad geographical distributions have a higher number, (ii) the abundance of ants negatively affects herbivore insect diversity, (iii) local plant diversity positively affects chewing herbivore diversity and (iv) local abundance of a specific host plant positively affects the diversity of sucking herbivores. The samples of insect herbivores were collected from 32 plants (16 plants of Erythroxylum suberosum and 16 of Qualea parviflora) by beating. A total of 71 ants (13 species) and 158 herbivorous insects (90 species) were collected from these two species of plants. The richness and abundance of the insect herbivores collected from E. suberosum differed from those collected from Q. parviflora. The abundance of ants negatively affected the diversity of sucking insects associated with E. suberosum. In addition, the interaction between the variables total plant richness per plot and ant abundance affected the diversity of chewing insects associated with E. suberosum. The density of Q. parviflora per plot affected the diversity of associated sucking insects. In addition, the interaction of the variables abundance of ants and abundance of Q. parviflora influenced the diversity of chewing insects. Our results indicate that there is no predominance of bottom-up or top-down forces in the organization of herbivorous insect communities in this area of tropical savanna, but the roles of these forces on insect communities are guild-dependent.

We investigated food niches, diet diversity and individual food specialization of the larvae and adults of four species of ladybirds, Sospita vigintiguttata (L.), Calvia quindecimguttata (F.), C. quatuordecimguttata (L.) and C. decemguttata (L.), co-occurring in European alder carr forests. The first two species are considered to be strict habitat specialists associated with alders (Alnus spp.) in marshy forests and the other two are less habitat-specialized, inhabiting various deciduous trees and shrubs. Our investigations were based on the analysis of food remains in frass produced by field-collected ladybirds. In each of the species studied, adults had more diversified diets than larvae based on Levins' D index of diversity. The most diverse diet recorded for adults was that for S. vigintiguttata followed by C. quatuordecimguttata, C. quindecimguttata and C. decemguttata. The diversity of larval diet was higher for the habitat specialists, C. quindecimguttata and S. vigintiguttata, than for the more habitat-generalists Calvia decemguttata and C. quatuordecimguttata. Although the main type of prey recorded for both adults and larvae of each of the species studied was aphids, other types of prey made up a relatively high part of the diet of different species/stage combinations. Psylla alni (L.), for example, was frequently recorded in the frass of adults and larvae of S. vigintiguttata and of adults of C. quatuordecimguttata and chrysomelid larvae commonly in the frass of adults and larvae of C. quindecimguttata. Quite a high proportion of the frass of all the species studied contained the remains of Psocodea. The niche width of adults was broader than that of larvae except in C. quindecimguttata in which it was the opposite. The larval niches of the strict habitat specialists, C. quindecimguttata and S. vigintiguttata, were broader than those of the less habitat-specialists C. decemguttata and C. quatuordecimguttata. Adults of all the species studied showed relatively higher levels of food specialization than larvae, except for C. quindecimguttata. The results of this study indicate that ecological specialization is a complex phenomenon and habitat specialization does not imply food specialization.

Invasive species disrupt the organization and functioning of many ant communities. Little is known about ant assemblages formerly in areas invaded by the little fire ant. In this study, we surveyed the same areas and compared the ant communities there when an invasive species first colonized the areas and 10 years later, using the same methodology (quadrat and baiting). A total of 83,299 worker ants from 17 species or morphospecies, in 4 subfamilies and 10 genera were recorded in the two periods sampled. Seven ant species were found to co-occur with W. auropunctata while 12 species were collected in the same area 10 years later, with no W. auropunctata recorded in any of the traps. In the absence of W. auropunctata, the number and diversity of ant species increased and the ant communities were dominated by the African big-headed ant, Pheidole megacephala. Our findings indicate that the disappearance of W. auropunctata is probably related to population increases in P. megacephala associated with dramatic changes in landscape. Further studies at other invaded locations should be carried out in order to reveal the generality of these patterns throughout this country.

The sex determination cascades in insects are diversified at the top of the cascade, where different primary molecular signals are employed, while at the bottom of the cascades, particularly the doublesex genes, are highly conserved. Here, we identified the doublesex ortholog (Btau-dsx) of Bactrocera tau, a pumpkin fruit fly, and found that Btau-dsx is composed of six exons and five introns with an additional short "m" exon located in the second intron. Btau-dsx is different from its orthologs in most dipteran insects: Its pre-mRNA is sex-specifically spliced to yield three (two male and one female) instead of two transcript variants. The two deduced proteins produced by the male-specific transcripts are a functional (Btau-DSX^M1) and a truncated (Btau-DSX^M2) protein, while the female-specific transcript produces the functional Btau-DSX^F protein. These three proteins contain all conserved domains except Btau-DSX^M2 which has no OD2 domain. The female-specific transcript is detected in both fertilized and unfertilized eggs and in both somatic and germ cells of the adult females, while the male-specific transcript is detected only in fertilized eggs and in the abdominal tissues and testes of adult males. The presence of the Btau-dsx^M1 transcript in fertilized eggs at the early syncytium stage suggests that in XY embryos, the Y-linked M factor gene may function quite soon after fertilization to alter the splicing pattern of Btau-dsx pre-mRNA from the female-specific to the male-specific mode. Injection of Btau-dsx^F dsRNA into recently emerging females can reduce the expression of vitellogenin (Btau-Vg) and causes some defects in the ovaries, indicating that Btau-dsx^F works upstream of Btau-Vg.

Daily rhythmicity in the sexual behaviour of Monema flavescens Walker (Lepidoptera: Limacodidae) was studied under laboratory conditions. There was a distinct diel periodicity in female calling, male responsiveness and mating behaviour of M. flavescens. As females aged there was an advance in the onset and more time spent calling. One day old females started calling 4 h after the onset of the scotophase, and 5 to 6 day old females called during the first hour of the scotophase. About 34.5% of females called on the night they emerged (1 day old) and the peak in calling of 97.8% was recorded for 2 day old females, after which the incidence of calling decreased rapidly with advancing age. Wind tunnel and copulation tests showed that males were sexually mature on the third night and female moths on the second night. The highest value for the percentage mating was recorded for 3 day old virgin females 4 to 6 h after the onset of the scotophase. In field tests, traps baited with 2 day and 3 day old virgin females captured more males than any other trap and most males were captured 4 to 6 h (1 to 2 day old), 3 to 5 h (3 to 4 day old) and 2 to 4 h (5 to 6 day old) after the onset of the scotophase. These results indicate that there is a daily rhythm in the reproductive behaviour of M. flavescens and provides a better understanding of its sexual behaviour.

Parental care in which females attend their offspring is recorded in over 30 species of ground beetles. Despite this, there is no quantitative data on the fate of the offspring when the mother is experimentally removed. This paper investigates parental care in Pterostichus anthracinus (Coleoptera: Carabidae). The objectives of the study were to estimate: (1) egg survival when the female is removed; (2) the ability of females to defend their eggs from attack by predators; (3) the ability of females to repair a damaged nest in which egg attendance takes place. In the laboratory, the reproductive activity of P. anthracinus lasted four months (from May till August) and peaked in late June. Mean (± SE) number of eggs in each clutch was 25.25 ± 2.19. All of the egg clutches were guarded by a female. Female attendance had no effect on egg mortality due to microbial attack. The duration of embryonic development lasted on average 5.2-5.3 days, and did not differ between the groups with and without maternal care. In P. anthracinus maternal care is important in preventing egg mortality due to predators. In the laboratory the percentage mortality of eggs without maternal care due to predators was 100%. In the group in which females attended their eggs, percentage mortality of offspring due to predation was about 51%. Female ability to repair damaged nests is important in preventing dehydration and reducing predation pressure. This laboratory study provides the first quantitative data on the importance of maternal care in ground beetles in determining the survival of their offspring.

The complete mitochondrial genome of a pyraloid species, Palpita hypohomalia, was sequenced and analyzed. This mitochondrial genome is circular, 15,280 bp long, and includes 37 typical metazoan mitochondrial genes (13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes) and an A + T-rich region. Nucleotide composition is highly biased toward A + T nucleotides (81.6%). All 13 protein-coding genes (PCGs) initiate with the canonical start codon ATN, except for cox1 which is CGA. The typical stop codon TAA occurs in most PCGs, while nad2 and cox2 show TAG and an incomplete termination codon T, respectively. All tRNAs have a typical clover-leaf structure, except for trnS1 (AGN) which lacks the dihydrouridine (DHU) arm. Comparative mitochondrial genome analysis showed that the motif "ATGATAA" between atp8 and atp6, and the motif "ATACTAA" between trnS2 and nad1 were commonly present in lepidopteran mitogenomes. Furthermore, the "ATAG" and subsequent poly-T structure, and the A-rich 3' end were conserved in the A + T-rich regions of lepidopteran mitogenomes. Phylogenetic analyses based on our dataset of 37 mitochondrial genes yielded identical topology for the Pyraloidea, and is generally identical with that recovered by a previous study based on multiple nuclear genes. In a previous study of the Crambidae, the Evergestinae was synonymized with Glaphyriinae; the present study is the first to clarify their close relationship with mitogenome data.

The mating behaviour of Pyrrhocoris apterus in the laboratory is well studied, but little is known about it under natural conditions. In natural populations in Central Europe, overwintered adults start copulating in March and continue until their death. Caged females, kept under natural conditions in the permanent presence of males, copulated repeatedly. Their mating activity increased sharply until early April, then very slowly until the end of June and then declined as the females die-off. Half of copulations were short (< 5 h) and only 9% were longer than 1 day. By contrast, in natural populations, mating activity (percentage of individuals involved in copula) reached its maximum in April and then decreased until early July, when the overwintered adults die. The decline in mating frequency (percentage of adults involved in copula) was associated with a decrease in the availability of receptive females towards the end of the mating period. For a female, repeated copulation is necessary because sperm is nearly depleted after insemination of 3-5 egg batches.

Movements are involved in several routine processes and may scale up to important ecological processes such as dispersal. However, movement is affected by a wealth of factors including flight capacity and behavioural traits. Both frequently differ in the sexes, which may well affect movement. We here aim to disentangle the relative importance of sexual differences in flight capacity versus behaviour on small-scale movements under controlled laboratory conditions in the temperate-zone butterfly Lycaena tityrus. The morphology of males is typically associated with increased flight capacity in this species. Nevertheless, the flight performances of the sexes did not differ, but the mobility of the females was higher. Thus, flight capacity and patterns of movement may not be intimately associated. Rather, the costs and benefits of flight seem to differ substantially between the sexes, with females being more mobile, potentially as a risk spreading strategy, while males are territorial and thus more sedentary. Thus, predictions regarding movement based on morphology are difficult.

Urban gardens can harbour a high diversity of insects, which are critically important components of urban ecosystems. In this work, we investigate the richness and diversity of a major taxon of economic and ecological importance, the aphids (Hemiptera: Aphididae), and their main insect predators, the hoverflies (Diptera: Syrphidae) and ladybirds (Coleoptera: Coccinellidae), in urban gardens. We examined how variation in environmental factors associated with urbanisation (garden host plant abundance, garden plant richness, garden size, proportion of impervious surfaces in the surrounding area) directly and indirectly (via prey and predator abundance) influence the local diversity and abundance of aphids, ladybirds, and hoverflies. Sixty-seven domestic gardens located in southern England were surveyed during the peak period of aphid abundance, and the numbers and identity of aphids and their predators were recorded. We observed 45 aphid species (179917 individuals in total), 15 hoverfly species (494 individuals) and 8 ladybird species (173 individuals). We found that aphid species richness and abundance were positively associated with utilised host plant abundance and garden plant species richness. Hoverfly abundance was positively correlated with garden plant richness. The abundance of ladybirds was positively correlated with aphid abundance and garden plant species richness, and negatively associated to the proportion of impervious surfaces in the surrounding environment. The difference in responses between the two major taxa of aphid predators may reflect differences in their behaviour and natural history. Our results indicate that overall increases in urban land cover are not favourable for ladybirds as a group, and that fine scale habitat variables that are determined by garden owners have the potential to greatly affect the diversity of aphids and their primary predators.

Estimating the spatial dispersion of pest arthropods is crucial for the development of reliable sampling programs and one of the main components of integrated pest management. The natural spatial distribution of a population of a species may be random, uniform, or aggregated and can be so classified based on calculation of variance to mean relations and related dispersion indices. In this work some classical density-invariant dispersion indices and related regression models are used for the first time to quantify the spatial dispersion of an important peach pest Anarsia lineatella Zeller (Lepidoptera: Gelechiidae) and construct fixed precision sequential sampling schemes. Taylor's power law, Iwao's patchiness regression and Nachman's model were used to analyse the damage to peaches caused by A. lineatella. All three regression models fit the data well, although the results indicate that Iwao's patchiness model provides a better description of the relationship between variance and mean density. Taylor's b and Iwao's b regression indices were both significantly smaller than 1, indicating that the distribution of individuals was uniform rather than random or aggregated. According to Green's and Kuno's models, the minimum sample size at the precision level of 0.2 varies from 3 samples, when total population density is more than 3 larvae/sample, to 10 samples, when population density is between 1 and 2 larvae/sample. Kuno's fixed sampling plan indicates that a small number of samples (i.e., 3-10 branches with fruit) is sufficient to estimate the mean population density of A. lineatella larvae with a precision of 0.2. The Resampling for validation of sampling plans (RVSP) method confirmed that the average level of precision of the fixed sequential plans matched the desired precision in most cases. The sampling plan presented here provides a level understanding of A. lineatella spatial ecology suitable for pest management decisions.

In some regions of Argentina and Brazil, the South American fruit fly Anastrepha fraterculus (Wied.) (Diptera: Tephritidae) causes significant damage to crops. An efficient integrated management program requires knowledge of pest population dynamics, dispersion patterns, sexual and oviposition behaviour, and adaptive landscape. The present study combined simple sequence repeat (SSR) molecular markers and morphometric datasets in order to analyse the population structure and infer the oviposition resource use strategy of the females. Infested guava fruits were collected from nine wild trees in Tucumán, Argentina, and a total of 140 adult A. fraterculus were recovered. These were then measured for six morphometric traits and 89 of them were genotyped for eight SSR loci. Genetic variability estimates were high (expected heterozygosity = 0.71, allelic richness = 12.5), with 8 to 20 alleles per locus. According to Wright's F-statistics estimates, the highest proportion (83%) of genetic variation occurred within individuals while variance between and within fruits were similar (≈ 8.5%). Analysis of the cryptic genetic structure based on SSR using different approaches, namely discriminant analysis of principal components (DAPC) and sparse non-negative matrix factorization (SNMF), yielded results consistent with the occurrence of two clusters with virtually no admixture. Average kinship between individuals which had emerged from the same fruit (0.07) was lower than that expected for full-sib families. Univariate and multivariate analyses of phenotypic data showed 54-66% of variance among individuals within fruits and 34-46% among fruits. The comparison between phenotypic (P_ST) and molecular (F_ST) differentiation identified wing width and length as possible target of positive selection. The average kinship and high genetic variation within fruits, together with the highly significant genetic differentiation among fruits, supports the hypothesis that each fruit was colonised by about three ovipositing females. The results also indicate that females were able to disperse widely from the emergence site before mating and starting oviposition activity.

Insects have evolved highly specific and sensitive olfactory sensory systems to detect plant hosts and mates. Chemosensory proteins (CSPs) play an important role in this process, but in this respect there is limited information on Clostera restitura, one of the most destructive defoliators of poplars in China. In the present study, we first identified seven candidate CSPs in C. restitura. Sequence alignment and phylogenetic analysis showed that these candidate proteins possessed typical characteristics of the insect CSP family and were similar to those of other Lepidoptera. These genes were expressed in different developmental stages and tissues, and the levels of expression differed after mating. Some CresCSPs were more associated with development and others with mating. They may play an important role in host recognition, egg development and mating behaviour. Furthermore, the CSPs were ubiquitously detected in all tissues and most of them were highly expressed in antennae, especially female antennae. We suggest the CresCSPs may contribute to female oviposition site recognition. CresCSPs that are highly transcribed in wings and legs, may function in gustation. This study provides a better understanding of the molecular mechanisms of olfaction in C. restitura and environmentally friendly pest management strategy for controlling C. restitura.

This paper reports a non-native Agrilus wood-boring jewel beetle reared from a stressed and non-native European beech (Fagus sylvatica) tree growing in New York City, USA. Results of two analyses using 759 DNA barcodes of Agrilus corroborate the morphology-based interpretation that this is the first North American record of an unnamed species from the A. roscidus species-group native to the Western Palaearctic. Taxonomy of the entire species-group requires revision, therefore we postpone formal description of the new species and refer to it as Agrilus sp. 9895. This is the 12^th non-native Agrilus established in North America. Prior to our study, members of the A. roscidus species-group were not known to develop in Fagus, therefore we hypothesise whether our record is a host plant shift linked to the human-mediated transatlantic dispersal, or a case of an elusive beetle escaping detection in Fagus in its unknown native range. All 759 herein analysed DNA barcodes of Agrilus (including, when present, specimen images and georeferences) are available online at dx.doi.org/10.5883/DS-VGDS010.

Insights can be gained by analysing the feeding decisions of animals in terms of nutrient demands at a species or community level. Using carbohydrate and protein food baits, resource use and food preferences of Formica (Serviformica) lemani were determined at nine locations situated at different altitudes (1875 to 2400 m a.s.l.) in the alpine grassland belt above the tree line in Austria and northern Italy. F. lemani is the most common species of ant in this habitat. Sucrose baits placed around ant colonies were visited by significantly (3.9 times) more workers than protein baits. This indicates that sources of sugar (carbohydrate) are in short supply in the alpine zone, whereas availability of prey items appears to be less constraining. Overall, we recorded a decrease in the incidence of visits to baits from low (31.9% baits attracting ants at least once) to high altitudes (16.7%). Foraging ants never visited 51.5% of the baits exposed for periods of 75 min. This indicates that with increasing altitude competition for food among ant colonies becomes less intense in alpine grassland ant communities.

The mid gut in insects is usually lined with a peritrophic membrane (PM), which protects it from microbial infections and physical contact with ingested food. Calcofluor is an optical brightener that has strong chitin-binding properties, which disrupt the chitin-protein structure of PM. In this study, we investigated the effects of calcofluor on the structure of the PM, activity of some common digestive enzymes and biological characteristics of the Indian meal moth, Plodia interpunctella (Lepidoptera: Pyralidae). Twenty hours after feeding on a calcofluor-containing diet, the PM was completely eliminated. We recorded significant effects of calcofluor on the activity of digestive enzymes in the mid and hindguts of larvae. In both these regions of the gut, in particular, there were significant increases in the activity of α-amylase, α-galactosidase and trypsin. The activities of α-glucosidase and β-glucosidase in the midgut of treated larvae were lower than in the control, but were significantly higher in the hindgut of treated larvae. The larvae that fed on on calcofluor for 20 h, took longer to complete their larval and pupal stages, were lighter in weight and fewer reached maturity and laid fewer eggs. Results of this and previous studies highlight the crucial role of PM in enzyme recycling and digestion. PM disruption may negatively affect insect development on the one hand, by decreasing the efficiency of food digestion and, on the other, by increasing the costs associated with an increased enzyme demand and disrupted enzyme recycling mechanism.

The olive fly, Bactrocera oleae (Rossi, 1790) (Diptera: Tephritidae), is the most important pest of olive trees globally, causing losses that, in the absence of control measures, can exceed 90% of the crop. In the Mediterranean basin, where the overwhelming majority of production is concentrated (~ 98%), organophosphate insecticides (OPs) have been the main tool for B. oleae control for the last four decades, leading to the development of resistance to these compounds. Mutations of the Ace gene, which codes for acetylcholinesterase, the target enzyme of OPs and other insecticides, have been identified as the underlying cause, with studies reporting mid to very high frequencies of resistance alleles in several countries. Interestingly, no resistance alleles were detected in Portugal, at the Western end of the Mediterranean basin. As the original study was done almost a decade ago and did not include many samples, we decided to re-evaluate the situation, by analysing a larger number of individuals from multiple locations in Western and Southern Iberia (Portugal and Spain). In our present study, resistance-associated Ace alleles were found to have become widespread in both regions, but with highly varying frequencies. Together with the observed haplotype distributions, this finding is consistent with previous suggestions of a recent, selection-driven spread and has implications for the importance of Ace mutations in organophosphate resistance in the field as well as the importance of gene flow between Mediterranean populations of B. oleae.

Identifying the plants aphids have fed on can increase our understanding of their roles in food webs, and help in improving management and implementation control strategies in agricultural systems. Field sampling and laboratory experiments were carried out to determine the stable isotope ratios of carbon (δ¹³C) and nitrogen (δ¹⁵ N) in three different varieties of cotton and the aphids (Aphis gossypii) that fed on these varieties. The results were used to test the hypothesis that stable isotope signatures of aphids that have fed on different varieties of cotton differ. Two-dimensional plots of stable isotope signatures for aphids and the cotton varieties they fed on displayed a non-overlapping pattern, indicating that stable isotope signatures of the three cotton varieties and the aphids that fed on them differed. The results indicate that stable isotope analysis can potentially be used to identify aphids that have fed on different varieties of cotton. When the stable isotope signatures of diets clearly differ then it is highly likely the consumers will be distinguishable.

Macrolophus pygmaeus Rambur (Hemiptera: Miridae) and Adalia bipunctata (L.) (Coleoptera: Coccinellidae) are two predatory insects commonly used as biological control agents. In order to determine the incidence with which both species attack and eat each other [Intraguild predation (IGP)], the direction and symmetry of the interaction between A. bipunctata and M. pygmaeus were characterized. In addition, whether the intensity of IGP between these two predators increased when the number of extraguild prey Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae) decreased, was also determined. Unidirectional sensu stricto IGP between A. bipunctata and M. pygmaeus was recorded: when IGP occurred, A. bipunctata was always the IG predator that killed and ate M. pygmaeus, the IG prey. However, the intensity of IGP was a function of the abundance of the extraguild prey, A. pisum, since IGP increased when the number of extraguild prey decreased. These results are discussed in terms of theoretical models that predict stability and the outcome of using natural enemies to control pests.

Cocccinellid beetles are largely diurnal species that are known to utilize visual cues in foraging and reproduction and to respond in specific ways to various light conditions. The present study evaluated the mating behavior and reproductive performance of Propylea japonica (Thunberg), a species indigenous to Asia, under various conditions of light intensity, photoperiod, and wavelength. Video-recording was used to continuously observe mating pairs for 24 h and a night vision system was employed to record nocturnal activity. Subsequently, males were removed and eggs were collected from females for 10 days and held under the same photic conditions to determine their fertility. The frequency and duration of copula varied among photic regimes in all experiments and tended to be negatively correlated, but more copulations occurred in photophase than in scotophase. White light at 1500 lux yielded higher egg production when compared to other light intensities, but egg fertility was higher at lower light intensities and highest in complete darkness, a result inferred to reflect egg sensitivity to light. Both fecundity and fertility were greater when 1500 lux white light was provided in a 16L : 8D photoperiod compared to shorter days. Green light yielded the highest net fertility compared to other wavelengths. A scheme is proposed to optimize photic conditions for reproductive adults of P. japonica and their eggs in colonies mass-reared for biological control applications.

Chestnut (Castanea sativa Mill.) is one of the economically more important trees in the north of Portugal. Spiders, as generalist predators, are potential controlling agents of pests, yet the composition of the community of spiders associated with this crop is only poorly known. The objective of this study was to determine the spider communities in the canopies of chestnut trees subject to three different soil management practices in northeastern Portugal. Three chestnut groves each subject to a different agricultural practice (grazed, tilled or untilled) were studied in 2008 and 2009. The Araneae communities were sampled by beating the branches and the individuals collected were identified to family and species when possible. To investigate the structure of the spider community in each grove the abundance and family richness of spiders were calculated and compared between managements. In total, 4172 spiders were collected and, in both years, the three most abundant families were Araneidae, Philodromidae and Linyphiidae. In 2008, there was a greater abundance of spiders in the grazed, followed by the tilled and untilled groves, but no significant differences among groves. However, in 2009 there was a greater abundance of spiders in the tilled grove, followed by grazed and untilled groves and the differences between the untilled and the other two groves were significant. Araniella, Oxyopes and Anyphaena were the most abundant genera in the three groves. This study showed that soil management may influence the diversity of spiders, but the effects were weak and not consistent between years. The reduction or absence of a suitable habitat for spiders under the trees in the tilled treatment might have resulted in the spiders migrating up into the canopy. However, based on the weak effects on spider abundance recorded and its potentially adverse effects on soils, tillage is not recommended for managing the incidence of pests in chestnut groves.

To study the component and gene expressions of apoptosome in the mitochondrial-associated apoptotic pathway, cytochrome c and Apaf-1 were identified in the diamondback moth (DBM), Plutella xylostella, collected from Fuzhou, China. The full-length cDNA of cytochrome c comprised 873 bp, including a 327 bp ORF encoding a putative protein of 108 amino acids. Two full-length cDNAs of Apaf-1, Apaf-1a and Apaf-1b, were identified. Apaf-1a shared the same region of 5'-UTR (5'-untranslated region) (172 bp) and ORF (4,647 bp) of cDNA, but was 73 bp longer than Apaf-1b in the region of 3'-UTR of the cDNA. The ORF of Apaf-1a and Apaf-1b encoded a putative protein of 1,548 amino acids and shared 100% identity. No significant up-regulation of cytochrome c mRNA expression was found in both the chlorpyrifos-resistant (R_R) and chlorpyrifos-susceptible (S_S) DBM. Compared with the control (at 25°C for 3 h), mRNA transcript levels of Apaf-1a and Apaf-1b increased with the increase of temperature and were significantly higher at 37, 42, 47 and 50°C than at 25 and 33.5°C in R_R DBM. However, the extent of up-regulation expression of Apaf-1a and Apaf-1b in S_S DBM was slight under heat stress except at 42°C. In general, significantly higher increase in the mRNA transcript level of Apaf-1a and Apaf-1b was found in R_R DBM than in S_S DBM. It has been suggested that significantly higher expression of caspase-7 and lower biological fitness occurs in R_R DBM under heat stress, a suggestion confirmed in our previous publications, and a result which might be associated with their higher up-regulation expression of Apaf-1a and Apaf-1b.