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The cryptic species that make up the Euwallacea fornicatus species complex can be readily distinguished via their DNA sequences. Until recently, it was believed that the Hawaiian Islands had been invaded by only one of these cryptic species, E. perbrevis (tea shot hole borer; TSHB). However, following the 2016 deposition of a DNA sequence in the public repository GenBank, it became evident that another species, E. fornicatus (polyphagous shot hole borer; PSHB), had been detected in macadamia orchards on Hawai'i Island (the Big Island). We surveyed the two most-populous islands of Hawai'i, Big Island and O'ahu, and herein confirm that populations of TSHB and PSHB are established on both. Beetles were collected using a variety of techniques in macadamia orchards and natural areas. Individual specimens were identified to species using a high-resolution melt assay, described herein and validated by subsequent sequencing of specimens. It remains unclear how long each species has been present in the state, and while neither is currently recognized as causing serious economic or ecological damage in Hawai'i, the similarity of the newly-confirmed PSHB population to other damaging invasive PSHB populations around the world is discussed. Although the invasive PSHB populations in Hawai'i and California likely have different geographic origins within the beetle's native range, they share identical Fusarium and Graphium fungal symbionts, neither of which have been isolated from PSHB in that native range.

Carrillo, J.D., Rugman-Jones, PF., Husein, D., Stajich, J.E., Kasson, M.T., Carrillo, D., Stouthamer, R., and Eskalen, A. 2019. Members of the Euwallacea fornicatus species complex exhibit promiscuous mutualism with ambrosia fungi in Taiwan. A number of ambrosia beetles have come to prominence in recent years because of the damage they inflict on a variety of trees within invaded habitats across the globe. Ambrosia beetles rely on symbiotic microorganisms, mainly fungi, as a dedicated food source and carry those microorganisms around with them within specialized organs termed mycangia. Investigation of members of the Euwallacea fornicatus species complex and their fungal symbionts in Taiwan revealed promiscuous symbioses with ambrosial Fusaria clade (AFC) members, Graphium spp., and Paracremonium spp. based on co-phylogenetic analyses. For AFC members, a novel diagnostic PCR assay targeting mating type genes MAT1-1-1 and MAT1-2-1 was developed and validated by amplicon size and sequencing. Mating type screening of AFC members revealed the isolates screened are all heterothallic (self-sterile), with both MAT types represented and recovered from fungi vectored by E. fornicatus (tea shot hole borer), E. kuroshio (Kuroshio shot hole borer), and E. whitfordiodendrus (polyphagous shot hole borer) in Taiwan. Members of the Euwallacea fornicatus species complex and the variety of ambrosia fungi they utilize further confirms that their relationship with these fungi are more likely promiscuous in native areas, as opposed to strictly obligate to a specific combination of fungi as observed in invaded areas.

BACKGROUND: Trichogrammatids are minute parasitoid wasps that develop within other insect eggs. They are less than half a millimeter long, smaller than some protozoans. The Trichogrammatidae are one of the earliest branching families of Chalcidoidea: a diverse superfamily of approximately half a million species of parasitoid wasps, proposed to have evolved from a miniaturized ancestor. Trichogramma are frequently used in agriculture, released as biological control agents against major moth and butterfly pests. Additionally, Trichogramma are well known for their symbiotic bacteria that induce asexual reproduction in infected females. Knowledge of the genome sequence of Trichogramma is a major step towards further understanding its biology and potential applications in pest control. RESULTS: We report the 195-Mb genome sequence of Trichogramma pretiosum and uncover signatures of miniaturization and adaptation in Trichogramma and related parasitoids. Comparative analyses reveal relatively rapid evolution of proteins involved in ribosome biogenesis and function, transcriptional regulation, and ploidy regulation. Chalcids also show loss or especially rapid evolution of 285 gene clusters conserved in other Hymenoptera, including many that are involved in signal transduction and embryonic development. Comparisons between sexual and asexual lineages of Trichogramma pretiosum reveal that there is no strong evidence for genome degradation (e.g., gene loss) in the asexual lineage, although it does contain a lower repeat content than the sexual lineage. Trichogramma shows particularly rapid genome evolution compared to other hymenopterans. We speculate these changes reflect adaptations to miniaturization, and to life as a specialized egg parasitoid. CONCLUSIONS: The genomes of Trichogramma and related parasitoids are a valuable resource for future studies of these diverse and economically important insects, including explorations of parasitoid biology, symbiosis, asexuality, biological control, and the evolution of miniaturization. Understanding the molecular determinants of parasitism can also inform mass rearing of Trichogramma and other parasitoids for biological control.

The Red Palm Weevil (RPW) Rhynchophorus ferrugineus (Olivier) is a voracious pest of palm species. In recent decades its range has expanded greatly, particularly impacting the date palm industry in the Middle East. This has led to conjecture regarding the origins of invasive RPW populations. For example, in parts of the Middle East, RPW is commonly referred to as the "Pakistani weevil" in the belief that it originated there. We sought evidence to support or refute this belief. First reports of RPW in Pakistan were from the Punjab region in 1918, but it is unknown whether it is native or invasive there. We estimated genetic variation across five populations of RPW from two provinces of Pakistan, using sequences of the mitochondrial cytochrome oxidase subunit I gene. Four haplotypes were detected; two (H1 and H5) were abundant, accounting for 88% of specimens across the sampled populations, and were previously known from the Middle East. The remaining haplotypes (H51 and H52) were newly detected (in global terms) and there was no geographic overlap in their distribution within Pakistan. Levels of haplotype diversity were much lower than those previously recorded in accepted parts of the native range of RPW, suggesting that the weevil may be invasive in Pakistan. The affinity of Pakistani haplotypes to those reported from India (and the geographical proximity of the two countries), make the latter a likely "native" source. With regards the validity of the name "Pakistani weevil", we found little genetic evidence to justify it.

BackgroundThe native microflora associated with mosquitoes have important roles in mosquito development and vector competence. Sequencing of bacterial V3 region from 16S rRNA genes across the developmental stages of Culex mosquitoes (early and late larval instars, pupae and adults) was used to test the hypothesis that bacteria found in the larval stage of Culex are transstadially transmitted to the adult stage, and to compare the microbiomes of field-collected versus laboratory-reared mosquitoes.ResultsBeta diversity analysis revealed that bacterial community structure differed among three life stages (larvae, pupae and adults) of Culex tarsalis. Although only ~2% of the total number of bacterial OTUs were found in all stages, sequences from these OTUs accounted for nearly 82% of the total bacterial sequences recovered from all stages. Thorsellia (Gammaproteobacteria) was the most abundant bacterial taxon found across all developmental stages of field-collected Culex mosquitoes, but was rare in mosquitoes from laboratory-reared colonies. The proportion of Thorsellia sequences in the microbiomes of mosquito life stages varied ontogenetically with the greatest proportions recovered from the pupae of C. tarsalis and the lowest from newly emerged adults. The microbiome of field-collected late instar larvae was not influenced significantly by differences in the microbiota of the habitat due to habitat age or biopesticide treatments. The microbiome diversity was the greatest in the early instar larvae and the lowest in laboratory-reared mosquitoes.ConclusionsBacterial communities in early instar C. tarsalis larvae were significantly more diverse when compared to late instar larvae, pupae and newly emerged adults. Some of the bacterial OTUs found in the early instar larvae were also found across developmental stages. Thorsellia dominated the bacterial communities in field-collected immature stages but occurred at much lower relative abundance in adults. Differences in microbiota observed in larval habitats did not influence bacterial community profiles of late instar larvae or adults. However, bacterial communities in laboratory-reared C. tarsalis larvae differed significantly from the field. Determining the role of Thorsellia in mosquitoes and its distribution across different species of mosquitoes warrants further investigation.

Microbes are important for mosquito nutrition, growth, reproduction and control. In this study, we examined bacterial communities associated with larval mosquitoes and their habitats. Specifically, we characterized bacterial communities associated with late larval instars of the western encephalitis mosquito (Culextarsalis), the submerged portions of two emergent macrophytes (California bulrush, Schoenoplectuscalifornicus and alkali bulrush, Schoenoplectusmaritimus), and the associated water columns to investigate potential differential use of resources by mosquitoes in different wetland habitats. Using next-generation sequence data from 16S rRNA gene hypervariable regions, the alpha diversity of mosquito gut microbial communities did not differ between pond mesocosms containing distinct monotypic plants. Proteobacteria, dominated by the genus Thorsellia (Enterobacteriaceae), was the most abundant phylum recovered from C. tarsalis larvae. Approximately 49% of bacterial OTUs found in larval mosquitoes were identical to OTUs recovered from the water column and submerged portions of the two bulrushes. Plant and water samples were similar to one another, both being dominated by Actinobacteria, Bacteroidetes, Cyanobacteria, Proteobacteria and Verrucomicrobia phyla. Overall, the bacterial communities within C. tarsalis larvae were conserved and did not change across sampling dates and between two distinct plant habitats. Although Thorsellia spp. dominated mosquito gut communities, overlap of mosquito gut, plant and water-column OTUs likely reveal the effects of larval feeding. Future research will investigate the role of the key indicator groups of bacteria across the different developmental stages of this mosquito species.

Eric D Bateman,1 Christopher O’Brien,2 Paul Rugman,2 Sally Luke,2 Stefan Ivanov,2 Mohib Uddin2,3 1Department of Medicine, University of Cape Town, Cape Town, 7700, South Africa; 2Research and Development, 3Respiratory, Inflammation, and Autoimmunity, IMED Biotech Unit, AstraZeneca, Gothenburg, SE-431 83, Sweden Objectives: To evaluate the efficacy and safety of AZD1981, a potent, specific antagonist of the CRTh2 receptor, as add-on therapy to inhaled corticosteroids (ICS) and long-acting β2-agonists (LABA), in patients with persistent asthma with an allergic component.Patients and methods: In this placebo-controlled, parallel-group Phase IIb study, patients with persistent atopic asthma on ICS and LABA were randomized to receive 12 weeks of treatment with placebo or AZD1981 (80 mg daily, 200 mg daily, and 10 mg, 40 mg, 100 mg, or 400 mg twice daily [BID]). The primary end point was the mean change from baseline in predose, prebronchodilator forced expiratory volume in 1 second (FEV1) averaged over weeks 2, 4, 8, and 12 in the AZD1981-treatment group vs the placebo group. Secondary end points included other measures of lung function, symptoms, and asthma control, as well as standard measures of safety.Results: In total, 1,140 patients (99.7%) received study treatment. There were improvements in the primary end point across all treatment groups over 12 weeks of treatment. However, the improvement for the highest AZD1981 dose (400 mg BID) vs placebo was not statistically significant (0.02 L, P=0.58), preventing interpretation of statistical testing for the lower doses. AZD1981 was well tolerated, and the incidence of adverse events was comparable across placebo and treatment groups.Conclusion: In patients with allergic asthma receiving ICS and LABA therapy, the addition of AZD1981 at doses up to 400 mg BID failed to produce a clinically relevant improvement in lung function or any other measured end point, but appeared to have an acceptable safety profile. This clinical study is registered with ClinicalTrials.gov (NCT01197794). Keywords: allergic asthma, AZD1981, CRTh2 antagonist, efficacy, safety, eosinophils

A molecular key for the identification of common Trichogramma (Hymenoptera: Trichogrammatidae) species found in agricultural settings around the Mediterranean is developed based on the sequence of the internal transcribed spacer 2 of the ribosomal cistron. Using the size of the ITS2 PCR product and restriction fragment length polymorphisms of the amplicon, ten Trichogramma species (T. bourarachae Pintureau and Babault, T. brassicae Bezdenko, T. cacoeciae Marchal/T. embryophagum Hartig, T. cordubensis Vargas and Cabello, T. dendrolimi Matsumura, T. euproctidis Girault, T. evanescens Westwood, T. nerudai Pintureau and Gerding, T. oleae Voegelé and Pointel, and T. pintoi Voegelé) can be distinguished.

We advance three propositions in this paper. First, teaching international business (IB) at any level needs to be theoretically driven, using mainstream frameworks to organize thinking. Second, these frameworks need to be made relevant to the experiences of the students; for example, by using them in case studies. Third, these parameters of rigor and relevance need to be seamlessly integrated. We then demonstrate these principles using Rugman's CSA-FSA matrix, describing both the theoretical and practical value of the framework. (Contains 1 figure.)

New country and host records of Trichogramma species for Turkey are presented. Trichogramma aurosum Sugonjaev & Sorokina is recorded for the first time from Turkey, and a new species, T. zerynthiae Polaszek & Bolu, is described. Morphological identification based on dissected male genitalia is supplemented by molecular sequence data. [ABSTRACT FROM AUTHOR]