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Little is known about winter-season parasitism of eggs of the corn leafhopper Dalbulus maidis DeLong (Hemiptera: Cicadellidae), an important pest of maize throughout the Americas. Our study, conducted in Mexico, aimed to characterize winter-season parasitism of corn leafhopper eggs on maize crops cultivated with drip irrigation and on wild grasses that grow on the edges of maize crops when maize is not present. Maize leaves baited with D. maidis eggs were used to trap the egg parasitoids in the field. In the first year (2022), parasitism of D. maidis eggs was investigated in maize fields planted contiguously on different dates (asynchronous planting). In the second year (2023), parasitism of D. maidis eggs was evaluated in edge grasses and in adjacent maize crops planted on the same date (synchronous). The highest percentage of parasitism (53%), percentage of emergence, and total abundance of egg parasitoids were found in asynchronous maize fields. Here, Anagrus virlai Triapitsyn (Hymenoptera: Mymaridae), Paracentrobia subflava (Girault) (Hymenoptera: Trichogrammatidae), and Pseudoligosita sp. (Hymenoptera: Trichogrammatidae) wasps were found parasitizing the D. maidis eggs, with P. subflava being the most abundant. In wild edge grasses, only P. subflava was found, showing low levels of parasitism, while in synchronous maize, P. subflava increased its percentage of parasitism (up to 37%), percentage of emergence, and abundance, during winter. These results suggest that P. subflava acts as an efficient biological control agent of D. maidis in irrigation-grown maize crops during the winter season, and that edge grasses are overwinter habitats for P. subflava.

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During the last decade, the spotted wing drosophila, Drosophila suzukii, has spread from eastern Asia to the Americas, Europe, and Africa. This fly attacks many species of cultivated and wild fruits with soft, thin skins, where its serrated ovipositor allows it to lay eggs in undamaged fruit. Parasitoids from the native range of D. suzukii may provide sustainable management of this polyphagous pest. Among these parasitoids, host-specificity testing has revealed a lineage of Ganaspis near brasiliensis, referred to in this paper as G1, that appears to be a cryptic species more host-specific to D. suzukii than other parasitoids. Differentiation among cryptic species is critical for introduction and subsequent evaluation of their impact on D. suzukii. Here, we present results on divergence in genomic sequences and architecture and reproductive isolation between lineages of Ganaspis near brasiliensis that appear to be cryptic species. We studied five populations, two from China, two from Japan, and one from Canada, identified as the G1 vs G3 lineages based on differences in cytochrome oxidase l sequences. We assembled and annotated the genomes of these populations and analyzed divergences in sequence and genome architecture between them. We also report results from crosses to test reproductive compatibility between the G3 lineage from China and the G1 lineage from Japan. The combined results on sequence divergence, differences in genome architectures, ortholog divergence, reproductive incompatibility, differences in host ranges and microhabitat preferences, and differences in morphology show that these lineages are different species. Thus, the decision to evaluate the lineages separately and only import and introduce the more host-specific lineage to North America and Europe was appropriate.

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Solitary bees and wasps that nest in cavities in tree trunks are important components of terrestrial ecosystems, providing pollination services, and in the case of wasps, the regulation of their prey populations. However, little is known about the vertical strata where bees and wasps build their nests. This is especially the case of urban forest remnants in the Amazon, which is relevant in the context of the global crisis in insect losses. We investigated the existence of vertical stratification in the nesting of solitary bees and wasps in an urban forest in Rio Branco, state of Acre, in the western Brazilian Amazon. We focused on whether wood temperature, ants, and termites are predictors of bee and wasp nesting. We sampled bee and wasp nests in the forest using trap-nests made with wooden blocks containing cavities with three different diameters for twelve months. Trap-nests were installed randomly at three heights in the forest. We collected 145 nests of 25 species, belonging to 11 genera and 6 families. A higher number of nests and species were collected in the upper stratum of the forest, strengthening the hypothesis that there is vertical stratification in the assemblage of solitary bees and wasps. Wood surface temperature and termite attacks on trap-nests were significantly different between strata, which may explain the vertical stratification of bee and wasp assemblages. Considering the importance of these insects for tropical forest ecosystems, the conservation of structurally complex and stratified forests is of paramount importance to maintain the diversity of this insect group.

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ABSTRACT We provide an update on the famelica species group, redescribing Leptogenys famelica Emery, 1896 and describing a new species, Leptogenys pujoli n. sp., based on worker specimens. The new species is smaller than L. famelica and can be distinguished by the indistinct mesometanotal suture, and the petiolar node with an anterodorsal margin mostly straight anterior to spiracle in lateral view. Leptogenys famelica is distributed from Costa Rica to Panama, while L. pujoli n. sp. is distributed throughout the Brazilian Amazon, from French Guiana to Bolivia. Some records previously attributed to L. famelica remain uncertain, potentially being either L. famelica or L. pujoli n. sp., or perhaps representing one or more undescribed species. We update the key to Leptogenys workers by Lattke (2011) and include images. We synthesize available knowledge about the possible biology of these species and propose that both L. famelica and L. pujoli n. sp. are generalist predators and that their reproduction is dependent on gamergates.

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Parasitoid wasps are fundamental insects for the biological control of agricultural pests. Despite the importance of wasps as natural enemies for more sustainable and healthy agriculture, the factors that could impact their species richness, abundance, and fitness, such as viral diseases, remain almost unexplored. Parasitoid wasps have been studied with regard to the endogenization of viral elements and the transmission of endogenous viral proteins that facilitate parasitism. However, circulating viruses are poorly characterized. Here, RNA viromes of six parasitoid wasp species are studied using public libraries of next-generation sequencing through an integrative bioinformatics pipeline. Our analyses led to the identification of 18 viruses classified into 10 families (Iflaviridae, Endornaviridae, Mitoviridae, Partitiviridae, Virgaviridae, Rhabdoviridae, Chuviridae, Orthomyxoviridae, Xinmoviridae, and Narnaviridae) and into the Bunyavirales order. Of these, 16 elements were described for the first time. We also found a known virus previously identified on a wasp prey which suggests viral transmission between the insects. Altogether, our results highlight the importance of virus surveillance in wasps as its service disruption can affect ecology, agriculture and pest management, impacting the economy and threatening human food security.

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Climate factors, pesticides, and landscape in coffee agroecosystems directly affect the populations of the coffee leaf miner and its parasitoids. This study aimed to investigate the effects of climate factors, insecticide use, and landscape on natural parasitism, parasitoid diversity, and infestation of L. coffeella in coffee plantations in the Planalto region, Bahia, Brazil. Mined leaves were collected monthly in six coffee plantations with varying edge density, vegetation cover, landscape diversity in scales of 500 to 3000 m of radius, insecticide use, and climate factors. Closterocerus coffeellae, and Proacrias coffeae (Eulophidae) predominated in the pest's natural parasitism. Our record is the first for the occurrence of Stiropius reticulatus, Neochrysocharis sp. 1, Neochrysocharis sp. 2, and Zagrammosoma sp. in Bahia. Higher temperature and larger forest cover increased the coffee leaf miner infestation. Higher rainfall values, insecticide use, and landscape diversity decreased the pest infestations. Natural parasitism and species diversity are favoured by increase in temperature, forest cover, and edge density, while increase in rainfall, insecticide use, and landscape diversity lead them to decrease.The natural parasitism and diversity of parasitoid species of the coffee leaf miner have been enhancing in the areas with greater forest cover and edge density associated with low use of insecticides. The areas composed of different lands with annual croplands surrounding the coffee plantations showed less natural parasitism and parasitoid species diversity. The ecosystem services provided by C. coffeellae and P. coffeae in coffee crops areas require conservation and these species are potential bioproducts for applied biological control programmes.

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Polybia paulista is a neotropical social wasp related to severe accidents and allergic reactions cases, including anaphylaxis, in southeastern Brazil. Antigen 5 (Poly p 5) is a major allergenic protein from its venom with potential use for component-resolved diagnostic. Therefore, the previous characterization of the immune response profile triggered by Poly p 5 should be evaluated. Recombinant Poly p 5 (rPoly p 5) was used to sensitize BALB/c mice with six weekly intradermal doses, and the specific antibody production and the functional profile of CD4+ T cells were assessed. rPoly p 5 induced the production of specific immunoglobulins (sIg) sIgE, sIgG1 and sIgG2a, which could recognize natural Poly p 5 presented in the venom of four different wasp species. rPoly p 5 stimulated in vitro the CD4+ T cells from immunized mice, which showed a significant proliferative response. These antigen-specific CD4+T cells produced IFN-γ and IL-17A cytokines and increased ROR-γT transcription factor expression. No differences between the control group and sensitized mice were found in IL-4 production and GATA-3 and T-bet expression. Interestingly, increased CD25+FoxP3+ regulatory T cells (Tregs) frequency was observed in the splenocyte cell cultures from rPoly p 5 immunized mice after the in vitro stimulation with both P. paulista venom extract and rPoly p 5. Here we showed that rPoly p 5 induces antigen-specific antibodies capable of recognizing Antigen 5 in the venom of four wasp species and modulates antigen-specific CD4+ T cells to IFN-γ production response associated with a Th17 profile in sensitized mice. These findings emphasize the potential use of rPoly p 5 as an essential source of a major wasp allergen with significant immunological properties.

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The stingless bees Tetragonisca angustula and Tetragonisca fiebrigi are widely distributed in Brazil, and both are commonly known as "jataí." Our goal was to investigate the possible origin of the B chromosomes in T. fiebrigi, a cytotaxonomic trait that differentiates T. fiebrigi from T. angustula. We analyzed diploid chromosome number (2n), B chromosome incidence, patterns of constitutive heterochromatin, and in situ localization of different repetitive DNA probes in T. angustula and T. fiebrigi. Both species displayed 2n = 34, with similar karyotype structures. One to three B chromosomes were observed in T. fiebrigi only. Constitutive heterochromatin was distributed on one arm of all chromosomes in both species, and T. fiebrigi B chromosomes were mainly heterochromatic with one euchromatic extremity. The (GA)15 and (CAA)10 microsatellite probes marked the euchromatic arms of all chromosomes in both species without marking the B chromosomes. The 18S ribosomal DNA (rDNA) probe marked 10 chromosomes in T. angustula and 6 A chromosomes in T. fiebrigi with an additional marking on 1B in individuals with 3B. The Tan-Bsp68I repetitive DNA probe marked the heterochromatic portion of all T. fiebrigi A and B chromosomes. This probe also marked the heterochromatic portion of all T. angustula chromosomes; therefore, both alternative hypotheses to the B chromosome origin are possible: (i) from the A chromosome complement of T. fiebrigi (intraspecific origin); or (ii) a by-product of genome reshuffling following the hybridization between T. fiebrigi and T. angustula (interspecific origin).

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Bees are the most significant pollinators of flowering plants. This partnership began ca. 120 million years ago, but the uncertainty of how and when bees spread across the planet has greatly obscured investigations of this key mutualism. We present a novel analysis of bee biogeography using extensive new genomic and fossil data to demonstrate that bees originated in Western Gondwana (Africa and South America). Bees likely originated in the Early Cretaceous, shortly before the breakup of Western Gondwana, and the early evolution of any major bee lineage is associated with either the South American or African land masses. Subsequently, bees colonized northern continents via a complex history of vicariance and dispersal. The notable early absences from large landmasses, particularly in Australia and India, have important implications for understanding the assembly of local floras and diverse modes of pollination. How bees spread around the world from their hypothesized Southern Hemisphere origin parallels the histories of numerous flowering plant clades, providing an essential step to studying the evolution of angiosperm pollination syndromes in space and time.

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Introdução: As reações de hipersensibilidade após vacinação contra a COVID-19 têm vindo a ser descritas, embora a anafilaxia seja rara. A hipersensibilidade ao veneno de himenópteros constitui a terceira causa mais frequente de anafilaxia em Portugal, embora não pareça aumentar o risco de anafilaxia à vacinação contra a COVID-19. Objetivos: Avaliar a segurança da vacinação contra a COVID-19 em doentes com história de alergia ao veneno de himenópteros referenciados dos Cuidados de Saúde Primários (CSP). Métodos: Estudo observacional retrospectivo com inclusão dos doentes com alergia ao veneno de himenópteros referenciados pelos CSP ao serviço de Imunoalergologia, para estratificação do risco de reações de hipersensibilidade à vacina contra o SARS-CoV-2, entre janeiro e dezembro de 2021. Resultados: No total, incluíram-se 18 doentes, 72% do sexo feminino, média de idades de 61±18 [21-89] anos. Na caracterização do tipo da reação ao veneno de himenópteros, as reações locais exuberantes corresponderam a 33% de todas as reações referidas. Quanto a sintomas sistêmicos de anafilaxia, foram referidos sintomas mucocutâneos (33%), respiratórios (28%), cardiovasculares (33%) e gastrointestinais (11%). A abelha foi o inseto mais frequentemente implicado (61%). Relativamente aos valores de triptase basal, 3 doentes apresentaram níveis acima do cut-off estabelecido de 11,4 ng/mL, tendo indicação formal para iniciar esquema de vacinação em meio hospitalar. Durante o processo vacinal registrou-se um total de 46 administrações em 18 doentes, todas sem intercorrências. Apenas 5 doentes foram vacinados em meio hospitalar, tendo sido os restantes encaminhados para os CSP. Os doentes com mastocitose confirmada ou suspeita foram submetidos à pré-medicação com anti-histamínico anti-H1 e anti- H2, bem como montelucaste, na véspera e no dia da vacinação. Conclusões: A vacinação contra a COVID-19 é segura em doentes com reação de hipersensibilidade ao veneno de himenópteros. O protocolo utilizado mostrou ser eficaz na segregação de doentes entre CSP e cuidados secundários/terciários.

Introduction: Despite numerous reports of hypersensitivity reactions to COVID-19 vaccination, anaphylaxis is rare. Although hypersensitivity reactions to hymenoptera venom are the third most common cause of anaphylaxis in Portugal, they don't appear to enhance the risk of anaphylactic reaction to COVID-19 vaccination. Objectives: To assess the safety of COVID-19 vaccination in patients with a history of hymenoptera venom allergy. Methods: This retrospective observational study included patients with hymenoptera venom allergy referred by primary health care to the Immunoallergology Outpatient Clinic of a tertiary hospital between January and December 2021 to stratify the risk of hypersensitivity reactions to the SARSCoV- 2 vaccine. Results: A total of 18 patients were included: 72% women; mean age 61 (SD, 18 [range 21-89]) years. One-third of all reported reactions to hymenoptera venom were large and local. Topical systemic symptoms of anaphylaxis were mucocutaneous (33%), respiratory (28%), cardiovascular (33%) and gastrointestinal (11%). The honeybee was the most frequently involved hymenoptera species (61%). The basal tryptase levels of 3 patients were above the established cut-off (11.4 ng/mL) and they were formally indicated for vaccination in a hospital setting. Concerning the vaccination process, 46 doses were administered to the 18 patients and no reactions were recorded. Only 5 patients were vaccinated in a hospital environment; the rest were referred to primary health care centers. Patients with confirmed or suspected mastocytosis were premedicated with anti-H1 and anti-H2 antihistamines, as well as montelukast, the day before and on the day of vaccination. Conclusions: COVID-19 vaccination is safe for patients with hypersensitivity to hymenoptera venom. The risk assessment protocol effectively designated patients to primary or secondary/tertiary health care.

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