Among the numerous factors that contribute to the success of social wasps, colony productivity is the most important and depends on ecological and environmental factors, such as the nest site. Consequently, nest-site choice should be determined by nest-site characteristics. The objective of this study was to determine on which species of plants Polistes gallicus wasps build their nests and identify the possible preferred features of plants used during nest-site selection by the foundress. From February to October 2017-2019 we recorded details of the nests in natural areas in south-western Spain (at 38° latitude). Nests of P. gallicus were recorded on 49 species of plants belonging to 23 families, with Scirpoides holoschoenus, Epilobium hirsutum and Foeniculum vulgare the most common. Significantly more wasps built their nests on herbaceous than on shrub and arboreal plants, and on "green" than "brown-grey" plants. Most of the nests were 21 to 189 cm above the ground, with a nest azimuth of about 102°. Nests were located at a mean distance of 43.51 ± 123.79 m from the nearest source of water. The length of the nesting season in the area studied was between 30 and 33 weeks, and more colonies were founded by a single foundress than several foundresses. Furthermore, a greater percentage of the single foundress colonies failed than of the multiple-foundress colonies.

The periodical cicadas of the genus Magicicada Davis, 1925 inhabiting eastern United States are characterized by a long juvenile period of 17 or 13 years and periodical mass emergence of adults. In this genus, only seven species are distinguished and are distributed into three species groups, Decim, Cassini and Decula. We performed comparative cytogenetic study of all seven Magicicada species, and 6 of them were explored for the first time. The techniques used included standard chromosome staining, differential chromosome staining techniques (C-banding, AgNOR-banding and fluorochrome DAPI-staining) and FISH (fluorescence in situ hybridization) with 18S rDNA and (TTAGG)_n-telomeric probes. All these species have holokinetic chromosomes, like other Hemiptera. Karyotypes of all species appeared to be remarkably conserved with 2n = 19/20 (18 + X0/XX) (male/female); one very large pair of autosomes and all other chromosomes constituting a decreasing size series; X chromosomes were indistinguishable, at least, at mitotic metaphases. The nucleolus organizer regions (NORs) revealed on one of the medium-sized chromosome pairs in all species and were shown to coincide with the rDNA clusters revealed by FISH. In all species, very small blocks of C-heterochromatin were variously located on chromosomes clearly using DAPI but less distinctly by C-banding. The chromosomes of all the species studied were confirmed to contain the "insect type" motif of telomeres (TTAGG)_n.

The African assassin bug genus Neopirates Miller, 1952, is revised. The type species, N. nyassae Miller, 1952, is redescribed and illustrated; two new species from Namibia, N. bicolor Liu & Cai sp. n. and N. xanthothorax Liu & Cai sp. n. are described and a key is provided to separate the three species of this genus. Sphodrembas fumipennis Swanson, 2019, the type species of Sphodrembas Swanson, 2019, is placed as a junior synonym of N. nyassae, resulting in Sphodrembas becoming a junior synonym of Neopirates. Morphological differences between Neopirates and similar genera and the distribution of Neopirates are briefly discussed.

Wolbachia is a maternally transmitted intracellular symbiont which causes reproductive distortions in the arthropods it infects. In recent years there has been an increasing interest in using Wolbachia as a potential tool for biological control by genetic manipulation of insect pests. In the present paper we report Wolbachia infection in several Trissolcus wasps (Hymenoptera: Scelionidae) which are important egg parasitoids of the sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutellaridae). We used DNA sequence data for a gene encoding a surface protein of Wolbachia (wsp) not only to confirm Wolbachia infection but also to discriminate Wolbachia strains. Phylogenetic analyses indicated that Wolbachia strains in Trissolcus species were closely related to one another and belonged to supergroup B. Determination of the infection status of various populations, the possible role of Wolbachia in causing the incompatibility and knowledge of the reproductive compatibility of Trissolcus populations is important for the success of parasitoids in sunn pest management.

Chenicoris dilatatus gen. n. & sp. n. from southern China is described and placed in the largest assassin bug subfamily Harpactorinae (Hemiptera: Heteroptera: Reduviidae). The new species is similar to members of Isyndus Stål, 1859 in general habitus, but can be distinguished from the latter by the unarmed anterior pronotal lobe, the laterally dilated lobe-like abdominal segment V and several features of its genitalia.

Horse chestnut leaf miner (Cameraria ohridella) has achieved ecological success by colonizing the entire European range of its primary host, horse chestnut (Aesculus hippocastanum). This insect has attracted the attention of scientists, but its ecology is poorly understood. Here, we investigated the effects of varying degrees of light availability on the leaf morphology of horse chestnut saplings and the performance of C. ohridella. A pot experiment under greenhouse conditions was performed in which the photosynthetic photon flux density (PPFD) was reduced from full light by 50% (high light - HL) or 80% (low light - LL). Insect performance parameters were quantified (i.e., pupal mass, efficiency of conversion of utilised leaf tissue (ECU) and potential fecundity). Compared with HL leaflets those from LL were characterised by higher contents of nitrogen and water but lower total phenolics. The oxidative capacity of phenolics (at pH ≈ 10, common in the lepidopteran gut) was low and did not differ in the two treatments. Compared with those collected from HL leaves, the mines of those collected from leaves of plants grown under LL conditions were larger in area but the leaf mass utilized by larvae was similar. Pupae were heavier in LL than in HL conditions, and ECU was higher in LL. The potential fecundity of females was not sensitive for experimental treatment. We conclude that (1) reduced light had a strong beneficial effect on the performance of C. ohridella and (2) phenolics in A. hippocastanum leaf tissues are a poor defence against this herbivore.

Exposed riverine sediments are unique riparian environments that exhibit high biodiversity and harbor many specialist species. Ground beetles are the most well studied inhabitants within these environments where they are often sampled using pitfall traps. In order to develop conservation measures for species occupying these habitats a logical first step is to refine sampling methods so that proper biodiversity assessments can be carried out. To that end, the effectiveness of two pitfall trap designs (standard trap vs. barrier trap) was evaluated. Over three sampling periods we collected 5,186 individuals represented by 43 species. Barrier traps proved to be superior, yielding significantly greater numbers of individuals (n = 3,456 vs. 1,730) than standard traps. Additionally, we collected more ground beetle species (37 vs. 30) in barrier traps than in standard pitfall traps. This study supports the rationale for deployment of more than one trap design to avoid deficiencies exhibited by a single type.

Biological parameters of the woolly whitefly Aleurothrixus floccosus (Hemiptera: Aleyrodidae) and its parasitoid Cales noacki (Hymenoptera: Aphelinidae) were determined at 25.0 ± 2.0°C, 50.0 ± 10.0% RH and a photoperiod of 14L : 10D on three different Citrus host plants. The percentage survival of A. floccosus ranged between 40.23 and 44.44%. The highest mortality was recorded in the first nymphal instar with mortalities ranging between 36.36 and 39.39%. On C. aurantifolia the total development time was 39.83 ± 0.68 days and the pre-oviposition, oviposition and post-oviposition periods 2.45, 10.68 and 1.68 days, respectively. Adult longevity was 15.0 days and average fecundity 73.27 ± 9.07 eggs. For C. noacki the pre-oviposition period was 0.8 days, oviposition period 4.38 days and post-oviposition period < 1 day. Adult longevity of C. noacki was 5.18 days and average fecundity 31.25 ± 2.87 eggs. The intrinsic growth rate (r_m ) of C. noacki (0.160) was significantly greater ( p < 0.05) than that of A. floccosus (0.076). The value of the finite rate of growth (λ) was also significantly ( p < 0.05) greater for C. noacki (1.173) than for A. floccosus (1.079). The larger values of r_m and λ recorded for C. noacki under experimental conditions indicate that this aphelinid has the potential to decrease populations of A. floccosus.

This study was on the effect of three species of aphids (Aphis fabae, Macrosiphoniella sanborni, Brevicoryne brassicae) on the survival, growth and development of the immature stages of the aphidophagous coccinellids Coccinella septempunctata, Ceratomegilla undecimnotata, Propylea quatuordecimpunctata and Oenopia conglobata. The percentage survival was lowest, immature development most prolonged and the adults the lightest when these predators were fed on B. brassicae. In addition, C. septempunctata and C. undecimnotata performed better when fed on M. sanborni (74.1 and 72.0% total immature survival, respectively) than P. quatuordecimpunctata and O. conglobata (25.0 and 13.8% total immature survival, respectively). In addition, the host plant of A. fabae also had a significant effect on the performance of the predators. These coccinellids survived best, had shorter developmental times and were heavier as adults when fed on A. fabae reared on Vicia faba than on Phaseolus vulgaris. These results may be useful for improving the effectiveness of biological control practice and the production of coccinellids in an insectary.

There are records of glands that produce sexual pheromones that are released into the environment or applied directly on sexual partners. Within Opiliones (Arachnida), several harvestmen in the suborder Laniatores have sexually dimorphic glands on legs I and IV, the mode of use of which is recorded only in two species but their function is unknown: while walking, males rub the glands against the substrate or against their body. Here we test an alternative and non-exclusive hypothesis that the glands present on the legs of male Gryne perlata (Cosmetidae) produce contact pheromones used in mating. We predicted that males would touch the females with the gland openings or with other male body parts previously rubbed by these glands. We also predicted that there are chemoreceptors on those parts of the females where males touch them. We analyzed 13 videos of G. perlata mating, a species in which the males have glands on legs I and IV of unknown function. We also analyzed 14 videos of Discocyrtus pectinifemur (Gonyleptidae) mating as a control, a species that lacks these glands. Finally, we looked for chemoreceptors on the legs of female G. perlata using a scanning electron microscope. During copulation, males of both species rubbed the legs of females with their first pair of legs, but not with the regions of these legs where the openings of the glands are. The fourth pair of legs were only used to support the body. Rubbing other body parts of the female by males with their glands was not observed during mating. Setae on the legs of the female did not have tip pores and therefore do not seem to be chemoreceptors. We therefore did not find any evidence that these sexually dimorphic glands in G. perlata release contact pheromones during mating.

The variegated caper bug (CB) Stenozygum coloratum (Klug, 1845) is common in the Eastern Mediterranean region and a minor agricultural pest. CB eggs were recently shown to serve as alternative hosts for Ooencyrtus pityocampae Mercet, 1921, an important natural enemy of the pine processionary moth (PPM) Thaumetopoea wilkinsoni Tams, 1924 (Lepidoptera: Notodontidae). In this study various aspects of the life history of CB were studied, including its distribution, host range, development, reproduction and ability to develop on various cultivated species of plants. CB occurs in almost all areas and habitats in Israel, except in the coldest regions, attacking several caper species (Capparis spp.). When reared on Capparis zoharyi at 25°C, one generation lasted 6 weeks and females laid a single 12-egg cluster every 3 days. Decreases in temperature, but not changes in day length, terminated reproductive activity. CB nymphs survived for up to three months, or even completed their development, on some agricultural plants. However, reproductive activity was initiated only if adults were fed capers. These findings emphasize the importance of capers in the CB life cycle and account for why other plants are rarely attacked. These plants may serve as a temporary refuge for CB when capers are scarce or unsuitable, mainly late in the season. Morphology of developmental stages, egg deposition, cannibalistic behaviour, sex ratio and effects of temperature on egg production were also studied. The possibility of using CB for enhancing the biological control of PPM is discussed.

Ingesting nutritionally imbalanced food can cause a significant reduction in fitness in insects. Insects can avoid the negative consequences of nutritional imbalances by selectively foraging for nutritionally complementary foods. We investigated the ability of the omnivorous beetle, Tenebrio molitor (Coleoptera: Tenebrionidae), to redress nutritional imbalances by selecting complementary foods. Beetles were fed one of three synthetic diets that varied in their protein: carbohydrate balance (p0:c42, p21:c21 or p42:c0) for 16 days and then allowed to select between two nutritionally imbalanced but complementary diets (p0:c42 vs. p42:c0) for 18 days. During the initial period, beetle survival was high on all three experimental diets, but their body composition was considerably skewed as a result of eating nutritionally imbalanced diets. Over the first 6 days of food choice (days 16-22), beetles previously fed a protein-rich, carbohydrate-deficient diet (p42:c0) preferred carbohydrate to protein, whereas those previously fed a carbohydrate-rich, protein-deficient diet (p0:c42) strongly preferred the protein-rich diet. When the food choice period continued for longer than 6 days, the selection of diets by previously carbohydrate-deprived beetles (p42:c0) was similar to that of the control beetles previously fed an optimal food (p21:c21). However, beetles that were previously fed on the protein-deficient diet (p0:c42) selected protein and carbohydrate equally throughout the remaining period of food choice and the cumulative protein-carbohydrate intake of these protein-deprived beetles was similar to that of those fed the optimal diet (p21:c21). At the end of the experiment, the body composition of all beetles was similar, indicating that the effects of nutritional imbalance on body composition were buffered by the subsequent selection of complementary foods. Our results demonstrate that T. molitor beetles are capable of redressing nutritional imbalances and indicate that the way in which the nutritional balance of beetles is restored depends on the nutrient that is initially deficient in their food.

Saproxylic organisms play a key role in a variety of forest ecosystem functions, which result in an increase in overall forest productivity and biodiversity. At present, dead wood is frequently removed from exploited forests. Estimating the effect of current forest management on biodiversity, and what gain in biodiversity would result from implementing restoration programs, requires the use of standardized sampling protocols. These protocols need to be suitable for use in different sampling areas and cost effective. In this paper, we developed, tested, and optimized a method for sampling saproxylic insects during a single visit to a sample site (i.e., the "grab-and-go" method). In the spring of 2011, we collected samples of downed decaying small and medium diameter wood debris in two Italian beech forests: Sega di Ala (Alps) and Vallombrosa (Apennines). We used ex situ emergence traps in the laboratory to collect the beetles emerging from the wood sampled. At both sites, the minimum number of wood samples that resulted in a satisfactory description of the saproxylic beetle assemblage was 20. Wood moisture, mean diameter, and geographical location were significantly associated with the beetle assemblages. We discuss the implications of using the "grab-and-go" method in large-scale forest monitoring programs. In this context, we recommend collecting at each site twenty 50 cm-long samples of wood lying on top of the litter, with a diameter of 12 ± 2 cm, cortex cover < 50%, and at Hunter's stage of decay class 2.

Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae) is an effective predator of pests of tomato crops and a promising biocontrol agent of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) in the Mediterranean area. The aim of this study was to determine the numerical response of N. tenuis to different levels of abundance of T. absoluta and its potential for controlling it when infesting tomato crops. The effects of infesting plants with either 0.2 or 2 larvae of T. absoluta and releasing either 2 or 0 adults of N. tenuis per plant were assayed in a complete factorial randomised-block design with 3 repeats in 12 greenhouse compartments in southern Spain. The population dynamics of the moth was similar in all compartments, with and without N. tenuis, but T. absoluta reached a lower absolute peak density in compartments with N. tenuis (29.1 ± 8.2 larvae per leaf) than in those without them (44.5 ± 19.4 larvae per leaf). The peak numbers of larvae of T. absoluta did not differ on the plants initially infested with 0.2 or 2 larvae. Nesidiocoris tenuis reached a maximum of 1.9 ± 0.43 and 3.0 ± 0.4 individuals per leaf in compartments in which low and high numbers of T. absoluta were initially introduced, respectively. The yield of tomatoes was higher in the treatments with N. tenuis than in those without, but the percentage of damaged fruit (> 50%) was similar. The slow numerical response of N. tenuis might have been due, among other things, to the poor establishment of this mirid due to the scarcity of prey. N. tenuis densities of about 0.2 individuals per leaf during the linear population growth phase of T. absoluta (0.5 to 3 larvae per leaf) did not prevent outbreaks.

Spalangia cameroni Perkins (Hymenoptera: Pteromalidae) is sold commercially as a biocontrol agent of filth flies, including the house fly, Musca domestica L. (Diptera: Muscidae). For this reason, S. cameroni is mass-reared for inundative releases to control harmful flies. However, the mass-rearing protocols include very little information on the influence of natal host on subsequent host selection by parasitoids with more than one potential host as in the genus Spalangia. Here, we report on the use of S. cameroni against M. domestica. The S. cameroni were reared using Ceratitis capitata Wiedemann (Diptera: Tephritidae) (natal host) pupae for several generations. Freeze-killed fly pupae were used in assays to determine the fecundity, number of adult progeny and sex-ratio of this parasitoid. Realized fecundity and number of adult progeny were greater when provided with house fly pupae than Mediterranean fruit fly pupae. Thus S. cameroni parasitized more house fly pupae than C. capitata pupae, even though the parasitoid was reared on Mediterranean fruit fly for many generations. These results indicate that S. cameroni reared on C. capitata can be successfully used in inundative releases against both fruit flies (agriculture) and house flies (livestock farming).

The Russian wheat aphid (RWA), Diuraphis noxia (Kurdjumov), is a serious pest of small grains and can cause losses of about 80% in wheat yields. Chemical control is ineffective against this pest so the combined use of host plant resistance and biological control is seen as a possible better means of controlling this pest. In this study, the potential effect of Omid (resistant) and Sardari (susceptible) cultivars of wheat on life table parameters and daily fecundity of RWA and its predator, Hippodamia variegata (Goeze), were determined using the age-stage two-sex life table theory. The results indicate that the r_m, R₀, λ, T and GRR of RWA were -0.005 ± 0.01 day^-1, 0.9 ± 0.24 offspring per individual, 0.99 ± 0.01 day^-1, 21.16 ± 1.79 days and 13.34 ± 2.91 offspring on Omid and 0.159 ± 0.01 day^-1, 6.9 ± 0.54 offspring per individual, 1.17 ± 0.01 day^-1, 12.14 ± 0.26 days and 12.73 ± 1.22 offspring on Sardari. The corresponding values for H. variegata fed on RWA reared on Omid were 0.24 ± 0.01 day^-1, 399.35 ± 53.01 eggs, 1.27 ± 0.01 day^-1, 24.67 ± 0.28 days and 544.23 ± 75.86 eggs and on Sardari 0.20 ± 0.006 day^-1, 221.56 ± 34.68 eggs, 1.23 ± 0.01 day^-1, 26.50 ± 0.41 days and 402.72 ± 67.55, respectively. The resistance of wheat cultivars significantly affected life table parameters and mean fecundity of RWA and H. variegata. Our results indicate that combining both host plant resistance and predators in the integrated pest management of RWA could result in a synergistic effect.

Quantitative community-wide moth surveys frequently employ flight-interception traps equipped with UV-light emitting sources as attractants. It has long been known that moth species differ in their responsiveness to light traps. We studied how the settling behaviour of moths at a light trap may further contribute to sampling bias. We observed the behaviour of 1426 moths at a light tower. Moths were classified as either, settling and remaining still after arrival, or continually moving on the gauze for extended periods of time. Moths that did not move after settling may not end up in the sampling container of the light trap and therefore are under-represented in automated trap samples relative to their true proportions in the community. Our analyses revealed highly significant behavioural differences between moths that differed in body size. Small moths were more likely to remain stationary after settling. As a corollary, representatives of three taxa, which in Europe are predominantly small species (Nolidae, Geometridae: Eupitheciini, Erebidae: Lithosiini), usually settled down immediately, whereas most other moths remained active on or flying around the trap for some time. Moth behaviour was also modulated by ambient temperature. At high temperatures, they were less likely to settle down immediately, but this behavioural difference was most strongly apparent among medium-sized moths. These results indicate the likely extent of the sampling bias when analysing and interpreting automated light-trap samples. Furthermore, to control for temperature modulated sampling bias temperature should always be recorded when sampling moths using flight-interception traps.

Encarsia sophia (Girault & Dodd) (Hymenoptera: Aphelinidae) is an important bio-control agent of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Storage at low temperature is a valuable method used in the mass rearing of biological control agents to ensure the availability of sufficient parasitoids when needed. However, storing parasitoids at a low temperature may lead to a decrease in their fitness. The aim of this study was to determine the effect of different durations of constant low temperature storage on the fitness traits of the above parasitoid. The effect of storage at three temperatures (4, 8 and 12 ± 1°C, RH = 65-75% and in darkness) for periods of 1, 2 or 3 weeks and at two pupal stages (10 and 12 days old) was studied. The percentage emergence, time to emergence, longevity, size and ability of the females that emerged to parasitize B. tabaci were evaluated. The results indicate that there is a decrease in percentage emergence, longevity and ability to parasitize the longer and lower the temperature at which the pupae of E. sophia are stored. The percentage emergence of both pupal stages kept at 12°C for a week was not affected. However, at lower temperatures (8 and 4°C) percentage emergence after storage of two weeks decreased to 67-87.5% and after three weeks none emerged. The time to adult emergence was longer for 12 day old pupae at all temperatures and storage times. The longevity of the adults that emerged from both pupal stages after one week of storage at 12 and 8°C was not affected, but decreased to 66-72% with increase in storage time. There was no effect of cold storage on adult size when 10 day old pupae were stored. The ability of this parasitoid to parasitize B. tabaci after emerging from both pupal stages stored at all of the temperatures regardless of storage time was significantly lower. Effect of storage at 12°C for a week in terms of percentage emergence and longevity did not differ from that of the control, but nevertheless they were less able to parasitize B. tabaci. Although the information on the effect of cold storage on E. sophia is very limited, the results of this study indicate that for more efficient biological control there is an urgent need to improve the method of storing pupae.

The average soil temperature was significantly lower in plots covered with hay. Hay mulching, however, did not increase significantly the total number of soil micro-arthropods collected using a soil pin trap and a soil sampler. Significant increases in the number of individuals was recorded only for certain groups. 64% of all the arthropods collected using soil pin traps were collected in hay-covered plots and 36% in control plots. This increase was statistically significant for the orders Entomobryomorpha and Poduromorpha of the subclass Collembola and surface-dwelling (epigeic) Coleoptera. For the samples collected using the soil sampler, 57% of the specimens were collected from hay-covered plots and 43% from control plots. As for the pin traps this was reflected in differences in the numbers of the orders Entomobrhyomorpha and Poduromorpha of the subclass Collembola and Pauropoda, collected in the treated and control plots. We conclude that mulching affected the different arthropod groups differently.

Cotton mealy bug, Phenacoccus solenopsis Tinsley, a polyphagous pest is a serious threat to cotton production in several parts of Southeast Asia. Lack of an effective predator against this pest has resulted in the use of intensive chemical-based management strategies. Studies were carried out under laboratory conditions to determine the functional response of the adults and nymphs of a generalist reduviid predator, Rhynocoris kumarii Ambrose and Livingston, to different population densities (1, 2, 4, 6, 8 and 10) of P. solenopsis. Males, females and nymphs of this reduviid showed a type II functional response. There was no significant difference in the attack rate of male and female R. kumarii; however, prey-handling times of the sexes differed significantly. Of the sexes, males were more aggressive and killed a significantly higher number of third instar mealy bugs than females and had a Holling type II curvilinear functional response. Functional responses of the nymphal instars (third, fourth and fifth) and adults (female and male) of R. kumarii were more pronounced than those of the first and second nymphal instars. Results indicate that the nymphal instars of R. kumarii can be more effective at regulating P. solenepsis than adult reduviids. The findings of this study are important as they demonstrate the considerable potential of R. kumarii for controlling the cotton mealy bug, but now need to be evaluated under greenhouse and field conditions.

Ophraella communa (Coleoptera: Chrysomelidae) is an oligophagous herbivorous beetle that feeds on Ambrosia artemisiifolia. It is native to North America, but was accidentally introduced into Japan in 1995 and Europe in 2013. We analyzed partial DNA sequences of the mitochondrial cytochrome oxidase II gene for O. communa collected from 29 locations in the United States, Japan and Italy. Overall, the results of our analyses indicate that the introduced Japanese populations have lower genetic variation than the native populations. The sequences for the Italian specimens did not share haplotypes with Japanese specimens. These results indicate that the introduced Japanese populations originated from a single introduction, and that the Italian and Japanese populations have different origins.

The ongoing process of climate change will result in higher temperatures during winter and therefore might increase the survival of overwintering invertebrates. However, the process may also lead to a reduction in snow cover and expose overwintering invertebrates to lower temperatures, which could result in higher mortality. During a field experiment, I investigated the effects of a reduction in snow cover on the survival of the ant Temnothorax crassispinus, which overwinters in nests located on the ground. Ant colonies differed in the survival rate of the workers in the experimental (from which snow cover was removed) and control group. In the control group, the survival rate was unrelated to colony size. However, in the experimental group, from which snow was removed after each heavy snowfall, worker survival was lower in small colonies. Such colony size related mortality may affect the fusion of colonies before winter.

Seeds of many species of plants may survive for a long time in the soil and germinate when brought to the surface, but whether they are subsequently eaten by seed predators is unknown. We examined the preferences of three species of carabids (Coleoptera: Carabidae) for 25 species of seeds and determined the difference in palatability between freshly dispersed and those buried for six years. The stability of their preferences was tested using a collection of seeds of different species, each of which was offered fresh or after being buried. Carabid beetles readily accepted previously buried seeds as food. In total, Pseudoophonus rufipes and Amara littorea ate more fresh seeds than previously buried seeds, while the opposite was true for Harpalus affinis. The seeds of some species were even more attractive to carabids after burial than in the fresh state. For all the species of carabids tested, the diet breadth was similar when the beetles were fed fresh or buried seeds, but the preferences for fresh and buried seed of particular species were correlated only in P. rufipes and A. littorea. We measured the seed characteristics (mass and viability) likely to be associated with the loss of attractiveness to carabids during burial. The change in carabid consumption was not related to changes in any of these characteristics. This finding indicates that factors responsible for variation in seed acceptability are complex. This study provides the first conclusive evidence that invertebrate seed predators will feed on seeds from seed banks, although they prefer fresh seeds.

Coprophagous insect communities play a critical role in the decomposition of vertebrate dung and provide ecosystem functions fundamental to modern agriculture. While the ecology of dung beetles is rather well understood, niche differentiation in coprophagous flies is poorly studied. Sepsid flies (Diptera: Sepsidae) are a vital part of the European community of coprophages, with 6-7 widespread species of Sepsis often found co-occurring in the same pasture. To advance our ecological understanding of the mechanisms that enable species to coexist, we investigated the oviposition preferences and larval performance of 7 common species of Sepsis in the dung of different large domestic and wild mammals. Substrate preferences and subsequent performance of larvae in laboratory experiments did not vary greatly. All species did very well on cow dung, the most common substrate in Central Europe, but also on dung of horse and wild boar. In contrast, flies did not prefer or grow well in dung of red and roe deer, two of the most common wild vertebrates. Thus there were only minor differences among the species tested along the specialist-generalist (dung) gradient, indicating that differences in the choice of oviposition sites by the adults of the different fly species and larval performance do not constitute a major axis of ecological differentiation. Nevertheless, there was a positive correlation between substrate choice and larval performance indicating the preference of gravid females for particular oviposition sites is adaptive. We conclude that sepsids are common in Europe because they are well adapted to the dung of herbivorous livestock rather than wild animals. Nevertheless, specialization on particular types of dung does not define the niche of Sepsis dung flies and hence plays a minor role in mediating their species diversity.

We investigated the effect of the feeding behaviour of young larvae of Pieris rapae crucivora Boisduval (Pieridae) on parasitism by the parasitoid wasp, Cotesia glomerata (L.) (Braconidae). Young, 1st-3rd instar larvae used approximately three sites for feeding each day. When not feeding, they moved a short distance away from the feeding sites (= feeding marks) and rested. For first, second and third instar larvae, the distances from the new mark, made within 24 h, to larva at rest were, respectively, about 3.5 mm, 5 mm and more than 10 mm. To resume feeding, they moved back to one of the former feeding sites or a new site. The percentage of the feeding marks older than 24 h that attracted parasitoids was less than 50%. Time spent searching for hosts by a parasitoid was short. Larvae placed 5 mm or more from a feeding mark were less parasitized than the larvae placed near a mark. The number of feeding marks affected parasitism. When comparing single-marked and triple-marked leaves, the percentage parasitism of the larvae on the latter was significantly lower than that of the larvae on the former. On triple-marked leaves, parasitoids visited each mark unevenly. Accordingly, the time spent searching each mark differed significantly among the marks. Because of this confusing effect, hosts are considered to be reducing the risk of parasitism. Our results demonstrate that the feeding habits of young larvae of P. rapae crucivora are adaptive in terms of reducing the risk of parasitism by C. glomerata.

Maternal effects of heat shock are reported for some species of insects, but little is known about such effects in the western flower thrips (WFT) Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). WFT is a pest of vegetables in greenhouses worldwide. It is susceptible to high temperatures in its natural environment and is controlled using heat treatment in China. WFT population growth is suppressed by a brief exposure to a high temperature of 40°C or 45°C in the laboratory. To explore the mechanism by which high temperatures suppress the growth of WFT populations, as well as the effects of multiple heat treatments on WFT, we recorded the duration of development and survival of immature WFT, and the sex ratio (female/male) and fecundity of F_1, F₂, F₃ and F₄ adult females that developed after a single heat shock, and those of F₂ offspring after a double heat shock. We also recorded the longevity and ovarian structure of adult females of the treated generation (P) and their F₁, F₂ and F₃ offspring after a single heat shock. In addition, we determined whether the effects of a heat shock on second instar nymphs and adults differed. The results indicate that exposure of the parental generation to 41°C or 45°C for 2 h significantly prolonged the duration of development, reduced survival of immature WFT and altered the sex ratio (female/male), longevity and fertility of their adult female offspring. The effects of a heat shock of 41°C persisted for two generations, whilst the effect of heat shock of 45°C persisted for three generations. In addition, double heat shocks had more pronounced effects than a single heat shock. Heat shock administered to second instar nymphs resulted in a decrease in the number of ovarioles, whilst a heat shock administered to adults resulted in ovariole deformity. The maternal effects of heat shock in terms of the biological parameters of WFT, structure and number of ovarioles, are critical in determining the suppression of the growth at high temperatures of WFT populations.

Circadian rhythms play an essential role in the adaptation of organisms to the environment and may show species-specific or sex-specific differences even within a closely related taxonomic group. Although spiders (Araneae) are sexually dimorphic in several morphological and behavioural features, there are very few studies on the sex-specific differences in their biological rhythms. This study evaluated the circadian rhythm in the locomotor activity of two agrobiont hunting species of spider, Carrhotus xanthogramma (Latreille, 1819) (Salticidae) and Philodromus cespitum (Walckenaer, 1802) (Philodromidae), under natural photoperiod conditions. Particular attention was paid to possible differences between the sexes in both species. We found that C. xanthogramma is a strictly diurnal species with a mean activity peak in the morning in both sexes and the females are more active than males. The locomotor activity rhythm of males was richer in ultradian (shorter than a day but longer than an hour) components, although the relative power of these components was negligible compared to the main, 24-h period component. In accordance with these results, the diel pattern of locomotor activity of C. xanthogramma can be described by a unimodal cosine curve. In contrast to C. xanthogramma, both sexes of Ph. cespitum showed cathemeral activity (i.e., activity occur within both the light and dark portions of the daily cycle) and females and males follow quite different activity schedules: females were most active at night, shortly before nautical dawn, whereas males were most active early in the morning. Unlike C. xanthogramma, Ph. cespitum has more ultradian components, with higher relative power especially in females, where besides the 24-h circadian component there is a particularly strong 12-h ultradian period. Based on these factors, females of Ph. cespitum show a bimodal and males a unimodal pattern.

Larvae of Strobilomyia flies (Diptera: Anthomyiidae) are serious pests in conifer-seed orchards because they feed on the seed inside the cones. Figitid parasitoids (Hymenoptera: Cynipoidea) of Strobilomyia larvae in conifer cones are commonly reported but under various generic names. It is argued here that, across the entire Holarctic region, these figitids belong to Amphithectus and perhaps also to Sarothrus (Figitinae), but not to Melanips (Aspicerinae), contrary to some reports. We conclude that the identity of the commonly found figitid associated with conifer cones (Larix and Picea) in Europe and Asia is Amphithectus austriacus (Tavares, 1928) comb. n. This is most likely considering the original description and the host association, although the type specimen of Seitneria austriaca Tavares, 1928 is lost. This species name takes priority over the recently described Amphithectus coriaceus Paretas-Martinez & Pujade-Villar, 2013. Seitneria Tavares, 1928 becomes a new junior synonym of Amphithectus Hartig, 1840, and Amphithectus coriaceus Paretas-Martinez & Pujade-Villar, 2013 becomes a new synonym of Amphithectus austriacus (Tavares, 1928) comb. n.

After high population densities of insect defoliators there is often a dramatic decrease in their abundance due to various limiting factors. Here, we compared gypsy moth larvae (Lymantria dispar L.) reared singly and in crowded conditions. We compared a number of physiological parameters of these insects and the effect of L. dispar population density on the activation of covert baculovirus infections in the larvae. It was found that the population density of gypsy moth larvae did not affect the mortality due to the activation of the covert virus infection or the total mortality. On the other hand, solitary-reared larvae were heavier, took longer to develop, and showed a four-fold higher concentration of dopamine in their haemolymph than larvae reared in groups. Thus, we demonstrated that an increase in the population density of larvae per se facilitates some changes in fitness and innate immunity traits but is not related to the activation of covert baculovirus infection. We suggest that an increase in population density does not increase the risk of epizootics triggered by the activation of covert baculovirus infection and that researchers should pay more attention to studying density-associated factors, such as starvation.

The morphology, physiology, behaviour and ecology of spiralling whitefly, Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae) on different host plants differ greatly. The genetic differences between the A. dispersus populations on 17 host plants were evaluated in the current study. Microsatellite markers were used to identify the presence of host-related genetic variation among A. dispersus populations. Our research clearly shows that there is a significant amount of genetic divergence among the A. dispersus populations on 17 host plants in India. The spiralling whitefly on acalypha and calotropis were genetically more distinct than whiteflies on other host plants. Various population genetic parameters, like heterozygosity, Nei's genetic distance, fixation indices (F_ST), source of genetic variation in AMOVA, etc. indicate that populations of spiralling whiteflies differ greatly genetically, probably because the spiralling whitefly populations on the Indian sub-continent came from multiple sources. The results of this study have implications for the quarantine protection strategy against this invasive pest.