The water scavenger beetle, Hydrophilus acuminatus (Motschulsky) (Coleoptera: Hydrophilidae), has two types of feeding modes: carnivorous during the larval stage and omnivorous during the adult stage. To investigate how the beetles detect food, larvae were provided with pond snails and snail visceral mass and adults were provided with algae and thawed blood worms. Larvae found snails and visceral mass hidden in the filter paper (only “smell” could be used); however, visceral mass was found 22–27 minutes sooner than snails, 40–53 minutes. Time to find the visceral mass that was exposed (all senses could be used) or hidden (only “smell” could be used) showed similar values, 5.4–8.0 or 7.6–8.5 minutes, respectively. Adults found algae exposed on the filter paper in 54 ± 73 minutes (mean ± standard deviation), whereas no adults found the algae hidden in the filter paper. In contrast, all adults found the thawed blood worms in the exposed (10.3 ± 13 minutes) and hidden conditions (11.0 ± 12.7 minutes). Adults did not show feeding behaviour towards the algae or thawed blood worms in the transparent microtube (only “sight” could be used). These suggest that larvae use smell, whereas adults use smell and touch and/or taste to detect their food.

Learning of chemical stimuli by insects can occur during the larval or adult life stage, resulting in changes in the imago chemotaxic behaviour. There is little information on learning in Tortricidae, and associative learning through metamorphosis is unknown in this group. Here, we evaluate the influence of olfactory aversive learning in Grapholita molesta (Busck) (Lepidoptera: Tortricidae) during the immature stage and determine if memory persists after metamorphosis. Larvae (10–12 days old) were conditioned to associate the odour of ethyl acetate with pulses of aversive electric shock. Insects were exposed to air, to the ethyl acetate odour, and to shock, in isolation or combination. After conditioning, both larvae and adults were tested in a two-choice olfactometer. Larvae exposed only to air or ethyl acetate increased legibility. Larvae trained with ethyl acetate and shock simultaneously exhibited significant avoidance to ethyl acetate. Avoidance was still present for at least 72 hours after metamorphosis. Thus, G. molesta has the ability to associate an odour to an aversive stimulus precociously, and this association is maintained through metamorphosis and persists into adulthood.

The sexual behaviour of the blister beetle Epicauta atomaria (Germar) (Meloidae: Meloinae: Epicautini), a pest that affects diverse crops of economic importance in South America, was evaluated for the first time under laboratory conditions. Twelve pairs of E. atomaria adults were collected from low-lying roadsides adjacent to grazed areas in Diamante, Entre Ríos, Argentina. To describe the sexual behaviour of this species, the number of events and their duration within different courtship phases in E. atomaria males were compared. An ethogram was built, showing that males perform three different behaviours during courtship phases: the quiescent period, antennal rubbing, and mounting. Our results showed that, during courtship, the number of events and the time of the mounting were low and significantly lower compared to behaviours undertaken during the quiescent period and antennal rubbing. In conclusion, the courtship of E. atomaria was clearly dominated by the quiescent period and antennal rubbing. To date, this is the first study to investigate sexual behaviour in E. atomaria, providing a foundation for future phylogenetic studies.

We investigated ecological patterns of richness and abundance of Anastrepha fruit flies, based on a long-term series with a dataset from 1998 to 2010, subdivided into four subseries describing pest management through the systems approach (integration of different measures, at least two of which act independently, with cumulative effects), and its impact on abundance and diversity of fruit flies. Richness and abundance were influenced by time and distance but to different extents. Spatio-temporal analysis taking into account the implementation of the systems approach revealed clear effects of the pest management on fruit fly richness and abundance. However, abundance was affected by the systems approach three years before richness was. Abundance and richness also showed different relationships with time and distance between orchards and forest. The Gompertz model, used to describe the relationship between area and species richness, was the function that showed the best fit to the data. The richness-partitioning analysis, which decomposes beta diversity, indicated different distributions of richness values and predictions for additive partitioning that were directly associated with the implementation of the systems approach. The spectral analysis projected different trends for peaks, indicating that the systems approach is able to delay the time for new population peaks of fruit flies.

Stephanitis pyrioides (Scott) (Hemiptera: Tingidae) is an important insect pest of azaleas, Rhododendron Linnaeus spp. (Ericaceae), in the United States of America. Because neonicotinoids, insecticides traditionally used against S. pyrioides, pose a risk to pollinators and natural enemies, nursery growers have reduced neonicotinoid use and are seeking alternative management options. Novaluron, an insect growth regulator, elicits a transovarial effect by reducing the viability of eggs after exposure to S. pyrioides adults. However, stability and persistence of transovarial effects on adults following exposure are not clear. The objectives of this study were to determine (1) the persistence of the transovarial effect of novaluron for up to three weeks after a single adult exposure and (2) the residual activity of aged novaluron residues eliciting a transovarial effect against S. pyrioides after a single application. Stephanitis pyrioides density was significantly lower in the novaluron-treated adults than in the nontreated controls for up to 21 days. The novaluron residues deposited on azalea foliage aged up to 32 days significantly reduced the number of S. pyrioides nymphs compared to that of the nontreated control. There was no significant difference in the number of nymphs among the 7-, 17-, and 32-day-old novaluron treatments relative to the nontreated control.

The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), can remain inside dry and deformed reproductive structures of cotton, Gossypium hirsutum Linnaeus (Malvaceae), known as dry bolls, during the cotton fallow to infest the next cotton crop. In this study, the influence of cotton cultivars and sowing densities on the formation of dry bolls was evaluated. In addition, dry bolls were dissected and internal structures that were related to boll weevil development were estimated. Finally, the presence and survival of boll weevils inside dry bolls were evaluated. The results indicate that the number of dry bolls, empty pupal cells, and emergence holes was influenced by cultivar and not by sowing density. Almost one-quarter (22.53%) of adult boll weevils examined was found alive inside the dry bolls after 10 weeks, which is slightly longer than the duration of cotton fallow in Brazil’s main cotton-producing regions. Therefore, remaining inside the dry bolls is an important survival strategy for boll weevils during the cotton fallow period, and cotton cultivars with a greater propensity for the formation of dry bolls might favour survival of the pest during this period.

The foxglove aphid, Aulacorthum solani (Kaltenbach) (Hemiptera: Aphididae), and the melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), are among the serious insect pests found in greenhouses. The efficacy of microbial control against these insects has been demonstrated and can be enhanced by the combination of different microbial agents. This study evaluated the efficacy of Bacillus pumilus Meyer and Gottheil PTB180 and Bacillus subtilis (Ehrenberg) Cohn PTB185, used alone and together, to control these two aphids both in the laboratory and in greenhouse on tomato, Solanum lycopersicum Linnaeus (Solanaceae), and cucumber, Cucumis sativus Linnaeus (Cucurbitaceae), plants. The results from the laboratory tests showed an increase in mortality induced by all biological treatments. In the greenhouse, all treatments induced mortality rates significantly higher than that of the control for A. solani. Similarly, all treatments performed better than the control against A. gossypii, significantly reducing its reproduction. Furthermore, we found no additive effects when mixing products nor negative interactions affecting survival for the bacteria investigated. These microorganisms therefore have potential for use in biological control.

Diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), was first recorded in North America from Europe about 150 years ago and can be a significant pest of canola in Western Canada. Because parasitism of P. xylostella in Canada is generally low, the introduction of one or more additional exotic parasitoids from Europe is being considered to increase the suppression of P. xylostella populations. Life table studies to determine the impact of parasitoids on diamondback moth populations in Europe were conducted in northwestern Switzerland in 2014–2016. Net reproductive rates were found to be less than one in seven out of eight life tables, suggesting that P. xylostella populations in Switzerland are mostly driven by immigration and recolonisation. In total, seven primary parasitoid species and one hyperparasitoid were associated with diamondback moth. Pupal parasitism by D. collaris reached up to 30%, but because generational mortality was mainly driven by abiotic mortality factors and predation of larvae, the overall contribution of pupal parasitism was low (< 6%). In regions of Canada, where P. xylostella may have increasing populations and low larval mortality, the addition of D. collaris may be a promising approach. Life table studies across Canada are necessary to determine the need for such intervention.

Several Drosophila species (Diptera: Drosophilidae) have become serious economic pests of berry and soft-skinned stone fruits around the world. Prominent examples are Drosophila suzukii (Matsumura), D. melanogaster (Meigen), D. hydei (Sturtevant), and D. immigrans (Sturtevant). Information on the biology and ecology of Drosophila is important for a better understanding of these important fruit pests and, ultimately, for fruit protection. In this study, the gut bacteriomes of these four Drosophila species were surveyed and the differences among bacterial communities were characterised. The 16S rRNA genes of gut microbes were sequenced by Illumina MiSeq technology (Illumina, San Diego, California, United States of America), followed by α-diversity and β-diversity analyses. The results show that bacteria of the family Enterobacteriaceae (Kluyvera and Providencia; phylum Proteobacteria) dominated all four Drosophila species. Specific dominant gut bacterial communities were found in each Drosophila species. The dominant families in D. melanogaster and D. suzukii were Enterobacteriaceae, Comamonadaceae, and Acetobacteraceae. In the intestine of D. hydei, Enterobacteriaceae had a proportion of 56.99%, followed by Acetobacteraceae, Spiroplasmataceae, and Bacillales Incertae Sedis XII. In D. immigrans, besides Enterobacteriaceae, Alcaligenaceae, Flavobacteriaceae, Xanthomonadaceae, Comamonadaceae, and Sphingobacteriaceae also had high relative abundance. These data expand current knowledge about the putative function related to gut microbes – for example, the metabolism of carbohydrates, amino acids, inorganic ions, lipids, and secondary metabolites. This knowledge provides a basis for further metatranscriptomic and metaproteomic investigations.

First North American records are presented for Cryptocephalus moraei (Linnaeus, 1758) (Coleoptera: Cryptocephalinae) and Psylliodes dulcamarae (Koch, 1803) (Coleoptera: Galerucinae: Alticini), as confirmed by morphology and DNA barcoding. Additional information is presented about phenology and host use for C. moraei, the first European Cryptocephalinae to be found elsewhere as conclusively adventive. Cryptocephalus moraei is expected to have no ecological impact on its host, the adventive Hypericum perforatum Linnaeus (Hypericaceae). However, P. dulcamarae, the second recently discovered flea beetle associated with the adventive Solanum dulcamara Linnaeus (Solanaceae), probably does harm that host. Both species are hypothesised to have arrived from Europe with woody plant material imported with soil during 1960–1965. A literature review of introduced Chrysomelidae found that Canada and the United States of America are together home to 68–78 species of adventive Chrysomelidae. All non-Bruchinae species among these are both native to Europe and occur either in Canada or both Canada and United States of America, except for intentionally introduced biological control agents and two species that feed on Eucalyptus L’Héritier de Brutelle (Myrtaceae). This suggests a dominant role of accidental introductions of cool-climate European species in recent unplanned additions to the fauna of leaf-feeding Chrysomelidae in North America.

Anelaphus villosus (Fabricius) and A. parallelus (Newman) are longhorned beetles (Coleoptera: Cerambycidae: Cerambycinae: Elaphidiini) that closely resemble each other in appearance. In practice, if antennomere 3 is distinctly longer than antennomere 4, the specimen is considered to be A. villosus, but the accuracy of this methodology is unknown. Authorities disagree about the ease of separating these two species based on morphological traits, and recent work hypothesises that they should be synonymised due to the difficulty of distinguishing them by either morphology or natural history. Assuming correct initial species determinations of curated specimens, as well as of those determined with DNA barcoding and by the primary author, data from 23 body measurements were collected from 50 A. villosus and 60 A. parallelus specimens. Stepwise discriminant analyses and discriminant functions were used to evaluate the ability to distinguish these species based on morphology. Species assignments from discriminant functions were very accurate and were supported by assignments determined with DNA barcoding. The ability to distinguish A. villosus and A. parallelus based on morphological and molecular differences provides evidence against the taxonomic hypothesis of synonymy under one species. A need for greater ecological understanding of these species remains.

Harvestmen (Arachnida: Opiliones) are soil animals with extremely low dispersal abilities that experienced allopatric differentiation. To clarify the morphological and phylogenetic differentiation of the endemic harvestman Zepedanulus ishikawai (Suzuki, 1971) (Laniatores: Epedanidae) in the southern part of the Ryukyu Archipelago, we conducted molecular phylogenetic analyses and divergence time estimates based on CO1 and 16S rRNA sequences of mtDNA, the 28S rRNA sequence of nrDNA, and the external morphology. A phylogenetic tree based on mtDNA sequences indicated that individuals of Z. ishikawai were monophyletic and were divided into clade I and clade II. This was supported by the nrDNA phylogenetic tree. Although clades I and II were distributed sympatrically on all three islands examined (Ishigaki, Iriomote, and Yonaguni), heterogeneity could not be detected by polymerase chain reaction–restriction fragment length polymorphism of nrDNA, indicating that clades I and II do not have a history of hybridisation. Also, several morphological characters differed significantly between individuals of clade I and clade II. The longstanding isolation of the southern Ryukyus from the surrounding islands enabled estimation of the original morphological characters of both clades of Z. ishikawai.

Orange wheat blossom midge, Sitodiplosis mosellana (Géhin) (Diptera: Cecidomyiidae), has been successfully reared in the laboratory for more than 20 years in Winnipeg, Manitoba, Canada. The rearing method has been developed to the point where it efficiently produces large numbers of wheat midge continuously under laboratory conditions for use in experiments on wheat midge biology and for screening wheat lines for crop resistance. Adult survival was extended by providing high humidity, and oviposition was increased by simulating natural dawn and dusk conditions and by supplying preflowering spring wheat to adults. Preventing desiccation of the wheat midge larvae in the wheat spikes before overwintering in soil and providing optimal cold conditions for a long enough period to break larval diapause enabled successful adult emergence. We provide data to facilitate the coordination of timing of wheat midge emergence from diapause with the wheat susceptible period. The method can be readily scaled up for screening many lines for resistance or scaled down for small experiments. Here, we report details of the rearing method so that others can implement it for research on the management of this internationally important pest.