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Kale is one of the main vegetables cultivated in Brazil due to its high nutritional value. Its leaves are mainly attacked by caterpillars, aphids and thrips, with the chemical control method being the most used in these cases. Predation on Thrips tabaci by the social wasp Polybia scutellaris was recorded in a small homegrown kale crop in southeastern Brazil, and this behavior was monitored for approximately three years. Predation occurred seasonally at the end of each dry season and it appears to be a species-specific interaction involving this particular predator-prey pair. No other social wasps species were observed preying on the thrips individuals during the observations. Our findings provide promising information that could be valuable for potential biological control strategies targeting pests affecting different crops. [ABSTRACT FROM AUTHOR]

Polybia is a common wasp genus found in most of South America. Polybia (gr. occidentalis) encompasses several species that are difficult to identify because of their similar morphologies. Our goal was to cytogenetically characterize three species belonging to Polybia (gr. occidentalis) and discuss the importance of cytogenetic data for integrative taxonomy. Polybia colonies were sampled from different regions of Brazil to perform classical and molecular cytogenetic analyses. Polybia paulista and Polybia sp. 1 showed 2n = 34 and 18S rDNA loci on two chromosomes, whereas Polybia sp. 2 showed 2n = 40 and 18S rDNA clusters on four chromosomes. The microsatellites GA(15), GAG(10), CAA(10), TTAGG(6), and TCAGG(6) showed similar distributions among the species, forming blocks in the euchromatic regions of the chromosomes, whereas CGG(10) did not yield any positive markings. In contrast, TAT(10) hybridized on the centromeric heterochromatin, showing differences in the number of marked chromosomes among the species. Therefore, it may potentially be a species‐specific cytotaxonomic marker in this group of wasps, but this feature needs further investigation. Fluorochromes evidenced that AT‐rich DAPI+ sequence distribution was coincident with heterochromatin, while the distribution of CG‐rich CMA3+ sequences was coincident with the 18S rDNA region. The present study revealed differences in diploid number, heterochromatin content, 18S rDNA sites, and microsatellite patterns between morphologically similar species, demonstrating the usefulness of cytotaxonomy in studying species complexes. [ABSTRACT FROM AUTHOR]

To identify viruses and compare their abundance levels in the venom glands of hymenopteran species, we conducted venom gland‐specific transcriptome assemblies and analyses of 22 aculeate bees and wasps and identified the RNA genomes of picornaviruses. Additionally, we investigated the expression patterns of viruses in the venom glands over time following capture. Honeybee‐infecting viruses, including the black queen cell virus (BQCV), the deformed wing virus (DWV) and the Israeli acute paralysis virus (IAPV), were highly expressed in the venom glands of Apis mellifera and social wasps. This finding suggests that the venom of bees and wasps is likely to contain these viruses, which can be transmitted horizontally between species through stinger use. Apis mellifera exhibited an increasing pattern of abundance levels for BQCV, DWV, IAPV and Triatovirus, whereas the social wasp Vespa crabro showed increasing abundance levels of IAPV and Triatovirus over different capture periods. This suggests that the venom glands of honeybees and wasps may provide suitable conditions for active viral replication and may be an organ for virus accumulation and transmission. Some viral sequences clearly reflected the phylogeny of aculeate species, implying host‐specific virus evolution. On the other hand, other viruses exhibited unique evolutionary patterns of phylogeny, possibly caused by specific ecological interactions. Our study provides insights into the composition and evolutionary properties of viral genes in the venom glands of certain aculeate bees and wasps, as well as the potential horizontal transmission of these viruses among bee and wasp species. [ABSTRACT FROM AUTHOR]

Non-aggressive interactions between Neotropical social wasps (Vespidae) and birds frequently occur but remain poorly understood. Typically categorized as commensalism, where birds benefit while no advantages for the wasps have been documented, the intricate dynamics of these associations have gone unexplored. These wasps, which are generalist feeders primarily relying on nectar, fruits, arthropods, and carrion, are seldom reported as vertebrate predators. In this study, we present a novel observation of the red social paper wasp, Polistes canadensis (Linnaeus, 1758) (Polistinae: Polistini), preying on young glittering-bellied emerald hummingbirds - Chlorostilbon lucidus (Shaw, 1812) (Apodiformes: Trochilidae), opportunistically recorded in the urban area of Brazilian Caatinga biome. Predation occurred when a Polistes canadensis individual targeted a hummingbird's nest. This occurrence challenges the prevailing view of these associations and suggests that social wasps may play a more significant role as nestling predators than previously acknowledged, highlighting the need for further research.

In Brazil, there are records of bird species from the Tyrannidae family that nest in association with social wasps, but there is no information about this interspecific relationship for the genus Phylloscartes. Therefore, this study records the occurrence of nesting by Phylloscartes sp.(Passeriformes) near a colony of the social wasp Polybia paulista in southeastern Brazil. The supposed reasons behind this possible interaction are discussed.

Social wasps are commonly considered generalists in their feeding habits, but there are genera with little information regarding their diet, such as Mischocyttarus de Saussure, 1853 (Hymenoptera: Vespidae), the most species-rich wasp genus in the world. The objective of this study is to report Mischocyttarus rotundicollis (Cameron, 1912) (Hymenoptera: Vespidae) feeding on a spider in the southeastern region of Brazil, aiming to expand information about its feeding behavior. The record occurred occasionally on September 23, 2023, in the state of Minas Gerais, Brazil, in the ecotone region between the Atlantic Forest and the Cerrado. The feeding of a species from the Araneidae family occurred in its web, and the individual of M. rotundicollis used the tarsi of its legs to cling to the silk threads of the web, which could suggest a specialization for the exploitation of this food resource. Our record provides further information on the feeding behavior and diet of M. rotundicollis and presents the first information on spider feeding by this species. Further studies are suggested to evaluate this possible hypothesis of specialization of the genus for foraging in spider webs.

Ropalidia chromis sp. nov. is described from the Democratic Republic of the Congo. It is characterized by a mixture of morphological features present in two large species groups of that genus, suggesting a separate phylogenetic lineage. [ABSTRACT FROM AUTHOR]

The study of relationships between living beings is essential for understanding the functioning of the ecosystem for the management and conservation of biota, especially in rich and threatened biomes such as the Brazilian Cerrado. Therefore, this study aims to report the occupation of abandoned social wasp’s nests by termites in this biome. In this study, the occupation of two abandoned nests of Synoeca surinama (L.) by the termite Nasutitermes obscurus (Holmgren), recorded by chance, in April 2023 in a gallery forest with the same vegetation type of the Cerrado, located in the Grande Sertão Veredas National Park in southeastern Brazil. Both social wasp nests had their cells occupied by termites, which may have been used as a satellite nest for N. obscurus. This is the first record of a termite species occupying a social wasp’s nests; however, further studies are needed to better elucidate this relationship.

Invasive vespids are able to disrupt native species assemblages, modify ecological dynamics, and degrade ecosystem services. However, it is often difficult to quantify such effects within invaded ranges, principally due to the complexity of interactions, and a lack of comparative pre-invasion controls. In this study, we thus examine the effects of an invasive hornet, Vespa velutina , upon native species densities and pollination in a major food plant, Hedera hibernica. Using the highly heterogeneous distribution of V. velutina in a coastal area of the northwestern Iberian Peninsula, we assessed the impact of differing hornet abundance on insect diversity, flower visitation frequency, and predator-prey interactions. We then examined resultant effects upon the pollination success of H. hibernica , in the form of fruit and seed set. Our results demonstrated that in areas with high V. velutina abundance, the floral visitation frequencies and durations of insect pollinators were significantly altered. Effects varied widely across insect families, reflected in the differing predation success rates of V. velutina upon various native pollinators, in tandem with competitive exclusion. Interestingly, V. velutina was itself a frequent floral visitor, becoming the most common nectar forager in areas where it was abundant. In spite of this, H. hibernica reproductive success was significantly degraded in these areas, resulting in reduced seed set. As such, V. velutina appears to have multidirectional effects upon pollination services, first as an insect predator, and second as a nectar competitor and pollinator. Crucially, our findings suggest that V. velutina is an inferior pollinator when compared to the native species that it displaces, resulting in a net reduction in pollination efficacy, and hence reproductive success in H. hibernica. This study thus reveals the profound effects of an invasive vespid on native species through both competitive and predatory interactions. [Display omitted] [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are widespread pollutants of emerging concern, and the risks associated with their ingestion have been reported in many organisms. Terrestrial environments can be contaminated with MPs, and terrestrial organisms, including arthropods, are predisposed to the risk of ingesting MPs. In the current study, the larvae of the paper wasp Polistes satan were fed two different doses (6 mg or 16 mg at once) of polystyrene MPs (1.43 mm maximum length), and the effects of these treatments on immature development and survival till adult emergence were studied. Ingestion of the two doses resulted in mortality due to impaired defecation prior to pupation. The survival of larvae that ingested 16 mg of MPs was significantly lower than that of the control. The ingestion of 16 mg of MPs also reduced the adult emergence (11.4%) in comparison to the control (44.4%). MPs were not transferred from the larvae to the adults that survived. These findings demonstrate that MP ingestion can be detrimental to P. satan, e.g. larval mortality can decrease colony productivity and thus the worker force, and that MPs can potentially affect natural enemies that occur in crops, such as predatory social wasps. [ABSTRACT FROM AUTHOR]

Potter wasps (Hymenoptera, Vespidae, Eumeninae) adopt different substrates for nesting, including other wasp nests. Nevertheless, such behavior rarely occurs with abandoned nests of the paper wasps (Hymenoptera, Vespidae, Polistinae). In this study, we report the occurrence involving the nesting of a potter wasp on a paper wasp's nest. Such a record occurred in November 2021 in a segment of a deciduous forest, at Mata Seca State Park, Southeast Brazil. An abandoned Polistinae nest was found, with 14 cells sealed with mud, from which four male Pachodynerus nasidens individuals emerged. This record of P. nasidens reusing a Polistinae's nest increases our knowledge of Eumeninae nesting strategies and on possible associations between different groups of vespid wasps. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three honeybee-infecting viruses from Aculeate species exhibited low codon usage bias. • The codon usage indices might affect the different codon usage patterns of the three honeybee-infecting viruses. • Only DWV exhibited a unique evolutionary pattern compared to the lineages of Aculeate species. To identify the evolutionary traits of honeybee-infecting viruses (HVs), including black queen cell virus (BQCV), deformed wing virus (DWV), and Israeli acute paralysis virus (IAPV), and their adaptation patterns in the venom gland of different hosts, we conducted a comparative analysis of codon usage patterns of venom gland-specific HVs in honeybees, solitary hunting, and social wasps. The nucleotides A and U, as well as the nucleotide composition at the third position of synonymous codons (A3s and U3s), were abundantly present with high frequencies in the polyprotein region of the three HVs in Apis mellifera , solitary hunting, and social wasps. Although the three HVs exhibited a high codon adaptation index, effective number of codons and the frequencies of GC3s were observed to be high and low, respectively, indicating a low codon usage bias in the three HVs. The relative abundance of dinucleotides, nucleotide compositions, and the aromaticity of amino acids might be considered as reasons for the different codon usage patterns of the three HVs in solitary hunting and social wasps compared to A. mellifera. The result of phylogenetic analysis revealed that DWV possesses a unique evolutionary pattern compared to the lineages of Aculeate species, possibly caused by specific ecological interactions. Our study provides further insights into the evolutionary aspects of venom gland-specific HVs in Aculeate species and might contribute as fundamental information for further research on the evolution of HVs. [ABSTRACT FROM AUTHOR]

Social wasp nests create an environment rich in resources, such as food and shelter, which consequently attract predators, parasites, and parasitoids. Parasitoids attacks can be one of the main causes of mortality among social wasps in the early stages of development. Therefore, the aim of this work is to report the occurrence of parasitoids in Mischocyttarus cassununga Von Ihering (Hymenoptera: Vespidae: Polistinae) nests, in an area of Cerrado, at the Federal Institute of Education, Science and Technology of Minas Gerais (IFMG) - Campus Bambuí, Brazil. There was an emergence of four parasitoids from two nests of M. cassununga, identified as Megaselia scalaris (Loew) (Diptera: Phoridae), the first record of this parasitoid in M. cassununga in a Cerrado area.

Ants prey on social wasps affecting the evolution of nest architecture, defense behaviors, and selection of nesting sites of these insects. The importance of social wasps in natural and agricultural ecosystems, especially in biological control, justifies studies on predation of these insects by ants. The objective of this work is to report the colony predation of the social wasp Agelaia vicina (de Saussure, 1854) and the nest occupation of Parachartergus pseudapicalis Willinck, 1959 (Hymenoptera: Vespidae) by the ant Camponotus renggeri Emery, 1894 (Hymenoptera: Formicidae) in the Atlantic Forest biome. The records occurred in 2015 and 2018 in southern Minas Gerais state, Brazil. This is the first record of C. renggeri preying on and occupying social wasp nests. This relationship between social wasps and ants constitutes an adaptation for the survival of these latter insects, and the limited number of records increases the need for research on the relevance of this phenomenon to the ecology of Atlantic Forest Hymenoptera.

Land use changes from native vegetation to agriculture, livestock grazing, and urban development are among the main problems related to biodiversity loss worldwide. In this paper we evaluate how land use changes (eucalypt plantation and pasture) affect the richness and assemblage of wasps (Braconidae, Ichneumonidae, Pompilidae, and Vespidae), in comparison with nearby areas with native vegetation in the Cerrado. Specimens were collected at six points, with two Malaise traps at each location. The collections were performed monthly for 10 d, for 12 mo. A total of 773 hymenopterans of the selected groups were collected, representing 253 species or morphospecies. Richness of the families Ichneumonidae and Pompilidae between the areas did not present significant differences. For the families Braconidae and Vespidae, the richness was greater in the eucalypt plantation and pasture areas compared to the native area. Species composition in the native habitat was different from either of the managed habitats in the studied environment. Furthermore, the composition of wasps in native areas varied less throughout the sampling campaigns when compared with the pasture and eucalyptus sites. In native areas, 85 exclusive morphospecies were found. Thus, changes in land use may cause changes in the composition of wasp species, since areas with native vegetation presented more heterogeneous and stable environments than the other land uses. The maintenance of native areas, even if close to planted forest and/or pasture areas, could be the best way to combine forest productivity with biodiversity conservation. [ABSTRACT FROM AUTHOR]

The social wasps of the order Hymenoptera, family Vespidae and subfamily Polistinae, perform important ecological functions such as pollination and predation, including pest insects, and can be an important resource in biological control. Some species of parasitoids attack nests of social wasps causing mortality in the early stages of development, thus impairing the biological control exercised by these insects. This study aimed to verify the occurrence and identify parasitoids in nests of Polistes versicolor Olivier, 1971, at the Instituto Federal de Educação, Ciência e Tecnologia de Minas Gerais (IFMG) - Campus Bambuí, Brazil. In total, 14 nests of P. versicolor were collected. The parasitism rate was 28.57%, and parasitoids were recorded in four of the 14 nests collected. The presence of parasitized nests may be due to the absence of a protective envelope, typical of the nest of P. versicolor. The emerged parasitoid belongs to the species Elasmus polistis Burks, 1971 (Hymenoptera: Eulophidae), a species identified in nests of social wasps only in the state of Rio Grande do Sul, southern Brazil. To the best our knowledge, this is the first study that shows the occurrence of E. polistis parasitizing social wasps in the state of Minas Gerais, southeastern Brazil.

Brain plasticity is widespread in nature, as it enables adaptive responses to sensory demands associated with novel stimuli, environmental changes and social conditions. Social Hymenoptera are particularly well-suited to study neuroplasticity, because the division of labor amongst females and the different life histories of males and females are associated with specific sensory needs. Here, we take advantage of the social wasp Polistes dominula to explore if brain plasticity is influenced by caste and sex, and the exploitation by the strepsipteran parasite Xenos vesparum. Within sexes, male wasps had proportionally larger optic lobes, while females had larger antennal lobes, which is consistent with the sensory needs of sex-specific life histories. Within castes, reproductive females had larger mushroom body calyces, as predicted by their sensory needs for extensive within-colony interactions and winter aggregations, than workers who frequently forage for nest material and prey. Parasites had different effects on female and male hosts. Contrary to our predictions, female workers were castrated and behaviorally manipulated by female or male parasites, but only showed moderate differences in brain tissue allocation compared to non-parasitized workers. Parasitized males maintained their reproductive apparatus and sexual behavior. However, they had smaller brains and larger sensory brain regions than non-parasitized males. Our findings confirm that caste and sex mediate brain plasticity in P. dominula, and that parasitic manipulation drives differential allocation of brain regions depending on host sex.

Eusocial insects are characterised by a reproductive caste differentiation such that egg-laying is restricted to a small number of queens. The majority of the colony members function as non-reproducing workers and gain indirect fitness by rearing the offspring of the reproductives. In primitively eusocial species, some workers can also get direct fitness by sneaking in some eggs in the presence of the queens, replacing the queens and becoming new queens, or initiating new nests. Here we aimed to understand the factors that permit some workers to gain direct fitness and alter the number of workers doing so, using the primitively eusocial wasp Ropalidia marginata. We transplanted 12 naturally occurring colonies into large laboratory cages where there was adequate space for the workers to leave their natal nests and initiate new colonies. We compared six control colonies that we provided with ad libitum food placed near the nest to six test colonies in which we hand-fed the wasps in addition to the ad libitum food. Wasps in test colonies consumed more food, showed more aggression, replaced their queens, and initiated new nests significantly more often than those in control colonies. When considering all 12 colonies, the rates of queen replacement and nest foundation were significantly positively correlated with food consumption rates. The additional nutrition gained by hand-fed wasps appears to help workers in test colonies to develop their ovaries and lay eggs, implying that they are nutritionally castrated in control colonies. [ABSTRACT FROM AUTHOR]

Epilepsy is one of the most common neurological diseases in the world. The objective of this research was to investigate a new peptide from the venom of the social wasp Chartergellus communis useful to the study or pharmacotherapy of epilepsy. The wasps were collected, and their venom was extracted. Afterward, the steps of fractionation, sequencing, and identification were carried out to obtain four peptides. These molecules were synthesized for behavioral evaluation tests and electroencephalographic assays to determine their antiseizure potential (induction of acute seizures using the chemical compounds, pentylenetetrazole – PTZ, and pilocarpine - PILO) and analysis of neuropharmacological profile (general spontaneous activity and alteration in motor coordination). Chartergellus-CP1 (i.c.v. - 3.0 μg/animal) caused beneficial alterations in some of the parameters evaluated in both models: PTZ (latency and duration of maximum seizures) and PILO (latency and duration of, and protection against, maximum seizures, and reduction of the median of the seizure scores. When evaluated in 3 doses in the seizure model induced by PILO, the dose of 3.0 μg/animal protected the animals against seizures, with an estimated ED 50 of 1.49 μg/animal. Electroencephalographic evaluation of Chartergellus-CP1 showed an improvement in latency, quantity, and percentage of protection against generalized electroencephalographic seizures in the PILO model. Further, Chartergellus-CP1 did not cause adverse effects on general spontaneous activity and motor coordination of animals. This study demonstrated how compounds isolated from wasps' venom may be important resources in the search for new drugs. Such compounds can be considered valuable therapeutic and biotechnological tools for the study and future treatment of epileptic disorders. In this context, a peptide that is potentially useful for epilepsy pharmacotherapy was identified in the venom of C. communis. [Display omitted] • Peptides can be versatile molecules for the development of new antiepileptic drugs. • Wasp venoms have been shown to be sources of neuroactive compounds. • A new peptide potentially useful for the treatment of epileptic seizures was isolated. [ABSTRACT FROM AUTHOR]

Inbreeding costs can be high in haplodiploid hymenopterans due to their particular mechanism of sex determination (i.e., single-locus complementary sex-determination system, sl-CSD), as it can lead to the production of sterile males. Therefore, mechanisms contributing to reduced inbred matings can be beneficial. In this sense, asynchronous nest departure of sibling drones and gynes could reduce kin encounters in social hymenopterans. Using six observation colonies, we determined under field conditions the nest departure behaviour of sibling reproductives of the social wasp Vespula germanica (Hymenoptera: Vespidae). We determined that sexuals leave the nests definitively and detected asynchronous departure not fixed to a particular caste at a seasonal scale in some colonies, as gynes or drones delayed their departure as a function of the departure of the opposite sex, depending on the colony. At a higher temporal resolution (i.e., within a day), we discovered that drones consistently began to leave nests 1 h before gynes and this difference was driven by those individuals that left on the same day as did the opposite-sex kin. Even though other mechanisms such as polyandry and differential dispersal could also be important at reducing inbred matings in the species, the observed departure patterns (i.e., in some colonies actually leave together with the opposite caste, while in others temporal segregation seems to occur) from nests could be complementary to the former and be important at reducing the negative effects of inbreeding in this invasive species. [ABSTRACT FROM AUTHOR]

Observations on the nesting characteristics and colony life of Mongolian social wasps are essential to the field due to the peripheral locations of species distribution ranges and critical lack of such information. We found 35 nests of seven social wasp species, including three vespine species (Dolichovespula saxonica, D. media and Vespula vulgaris) and four polistine species (Polistes snelleni, P. riparius, P. nimpha and P. biglumis). Riparian woodland was the habitat where the most species (five out of seven) nests were found. Nests of P. snelleni, Baikal-Far Eastern species, were found only in river cut banks, in holes probably originally excavated by passerine birds most likely sand martin (Riparia riparia). Nesting sites of D. saxonica were the most diverse (bank hole, underground, aerial and birch stump/logs). Colony size of vespine wasps in northern Mongolia was relatively small (36-60 individuals). Nests of Polistes species (except P. snelleni) were found frequently on the branches of willow (Salix sp.) and wild rose (Rosa acicularis). Other characteristics associated with each species nest were considered separately.

Polistes stigma is a common social wasp found in continental Southeast Asia. Despite its wide distribution and abundance, hitherto, there are no studies on small or medium molecular weight components of the venom. For the first time, this study has described the amino acid sequences and its post-translation modifications (PTM's) of four wasp-mastoparans (Ps 1524, Ps 1540, Ps 1556 and Ps 1630), three chemotactic peptides (Ps1417, Ps1434 and Ps1474) and one more (Ps1549) lysine rich peptide from the venom of P. stigma. There were 27 mass traces obtained from the crude natural venom, in which the complete amino acid sequences of 8 peptides were solved. Further, single disulphide bonded peptides uncommon in wasp venoms were identified. The mastoparan peptides were rich in hydrophobic residues. In addition, the peptides Ps1549, Ps1630, Ps1434 and Ps1417 were found to have unusual PTM's of C-terminal amidation. This preliminary study comprehends the untapped compounds present in wasp venom that are equally valuable to widely studied venoms of snakes, spiders and cone snails. [ABSTRACT FROM AUTHOR]

The State of Rio Grande do Sul is a major producer of grapes in Brazil, highlighting the Serra Gaúcha as the main producing region. In the pursuit of good quality in grapes it is essential the control of pests, especially insects. This study highlights the incidence of wasps, which cause serious damage at harvest time. This study aimed to characterize the community of social wasps (Hymenoptera, Vespidae) through faunal analysis and to examine the relationship of these insects with injuries to the grape berries in vineyards of Bento Gonçalves, Rio Grande do Sul State. Therefore, active search were made in January and February 2014, followed by analysis of frequency, constancy, abundance, dominance and diversity. Ten species of wasps were able to use grape berries as food. The two dominant species were Polybia ignobilis and P. minarum, however, Synoeca cyanea has greater ability to break the intact berries. Other three species, Polistes cavapytiformis, P. versicolor and Brachygastra lecheguana, were also able to break the skin of grapes, but of damaged berries.

Non-random space use is common among animals across taxa and habitats. Social insects often use space non-randomly, outside as well as inside their nests. While such non-random space use outside the nest may improve foraging efficiency, inside the nest, it is often associated with the efficient division of labour. Non-random space use by adults on their nests has been hypothesized to result from dyadic dominance interactions, non-random distribution of tasks, differential activity levels, workers avoiding their queens or prophylactic avoidance of disease spread. These hypotheses are generally derived from species in which the tasks of the workers are themselves non-randomly distributed on the nest. Here, we study the primitively eusocial wasp Ropalidia marginata, in which tasks are not distributed non-randomly, and show that 62.4% ± 16.2% of the adults nevertheless use space on their nest non-randomly. In this species, we find that nonrandom space use may help optimizing nutritional exchange between individuals while prophylactically minimizing disease spread among nestmates. We did not find evidence for the roles of dominance interactions, activity levels or location of larvae in non-random space use. Spatial organization appears to be a mechanism of minimizing the costs and maximizing the benefits of social life. [ABSTRACT FROM AUTHOR]

Two species of social wasps have established in the Faroe Islands in 1999 -- common wasp Vespula vulgaris and German wasp Vespula germanica. The population growth, and dispersal in the Faroes has been followed in detail through correspondence and contact with local residents and authorities throughout the Faroes. Collected wasps have been identified, and nest eradication data from the local municipalities is also presented. In total there have been 1.222 nests located and destroyed, mostly in Tórshavn, where they were first introduced, but nests have also been found on neighbouring islands. Both the introduction and the spread within the Faroes suggest a strong relationship with human settlements and travel. Social wasps have established on four out of 18 islands -- all of which are connected by land, suggesting that their spread within the islands is also human aided. With no active biosecurity measures to prevent the introduction of invasive alien species to the Faroes, we predict that the introduction of more species of social wasps to be very likely, and wasps already present will likely invade new islands. Although social wasps represent a public nuisance in the Faroes, the potential ecosystem impacts are grossly underappreciated and understudied. [ABSTRACT FROM AUTHOR]

Abstract. The success of social wasps is highly dependent on nest construction and colony maintenance. Species use different strategies to avoid nest predation, including forming associations with other insects and vertebrates. This study describes for the first time the association between the social wasp Chartergus globiventris Saussure and the yellow-olive flycatcher Tolmomyias sulphurescens Spix in a deciduous seasonal forest fragment in southeastern Brazil. We located eight active C. globiventris colonies in the study site, three of which were associated with active T. sulphurescens nests. Bird-wasp associations in previous studies have been regarded as commensalism because only birds seem to benefit. However, further studies are needed to better understand the potential benefits of this relationship for both taxa. Associações de nidificação entre Chartergus globiventris Saussure (Hymenoptera: Vespidae) e Tolmomyias sulphurescens Spix (Passeriformes: Tyrannidae) no sudeste do Brasil Resumo. O sucesso das espécies de vespas sociais está relacionado tanto a construção quanto a manutenção das colônias. Várias espécies utilizam de diversas estratégias para evitar a predação de seus ninhos, como a associação com outros insetos e vertebrados. O presente estudo descreve o primeiro registro da associação da vespa social Chartergus globiventris Saussure com a ave Tolmomyias sulphurescens Spix em fragmento de Floresta Estacional Decidual no Sudeste do Brasil. Foram registradas oito colônias de C. globiventris ativas em diferentes espécies arbóreas, das quais três estavam associadas a ninhos ativos de T. sulphurescens. A associação entre a ave e a vespa tem sido tratada como comensalismo, pois apenas a ave obtém vantagens aparente, como discutido na literatura. Contudo, é necessário realizar experimentações ou análises mais aprofundadas a fim de se obter afirmações sobre os benefícios dessa relação.

The parental investment (PI) theory predicts that animals that have the ability to care for their offspring should defend them with an optimal intensity to minimize the risks of predation. This study evaluates the stages of development that are more valued and, therefore, are more protected by the colonies of the founding wasp Parachartergus pseudoapicalis. We determined the effects on the colony defense intensity of colony size, adult population, and immature population size for different stages. As predicted by PI theory, we found that defense intensity was related to colony investment in offspring. In addition, we found no association between the number of adults in the colony and the defense intensity, whereas a greater number of immatures in the pupal stage in the colony led to greater defense intensity. Our study highlights the importance of parental care in social insects and the changes in defense behavior present in colonies with different compositions of individuals at different stages. [ABSTRACT FROM AUTHOR]

ABSTRACT Nectarinella manaura sp. nov. is described, representing the first record of the genus from Brazilian Amazonia. Its description raises richness for Nectarinella from two to three species, and extends the range of characteristics for the genus, especially in terms of body size and color patterns. Discovery of the new species may shed new light into the knowledge of phylogenetic relationships between Nectarinella and other closely related genera.

To identify and compare venom components and expression patterns, venom gland-specific transcriptome analyses were conducted for 14 Aculeate bees and wasps. TPM (transcripts per kilobase million) values were normalized using the average transcription level of a reference housekeeping gene (dimethyladenosine transferase). Orthologous venom component genes across the 14 bee and wasp species were identified, and their relative abundance in each species was determined by comparing normalized TPM values. Based on signal sequences in the transcripts, the genes of novel venom components were identified and characterized to encode potential allergens. Most of the allergens and pain-producing factors (arginine kinase, hyaluronidase, mastoparan, phospholipase A1, phospholipase A2, and venom allergen 5) showed extremely high expression levels in social wasps. Acid phosphatase, neprilysin, and tachykinin, which are known allergens and neurotoxic peptides, were found in the venom glands of solitary wasps more often than in social wasps. In the venom glands of bumblebees, few or no transcripts of major allergens or pain-producing factors were identified. Taken together, these results indicate that differential expression patterns of the venom genes in some Aculeate species imply that some wasps and bumblebee species have unique groups of highly expressed venom components. Some venom components reflected the Aculeate species phylogeny, but others did not. This unique evolution of specific venom components in different groups of some wasps and bumblebee species might have been shaped in response to both ecological and behavioral influences.

Nesting substrata, colony success and productivity of the wasp Mischocyttarus cassununga. Colonies of the wasp Mischocyttarus cassununga (von Ihering, 1903) are easily found in urban areas. However, in spite of the massive presence of this species in cities, little is known about its nesting habits, colony success and productivity. The present study aimed at answering the following questions: What are the substrates used for nesting by M. cassununga? What is the main foundation strategy adopted by M. cassununga in urban areas: a solitary female or associative foundation? Is there a relationship between foundation strategies and colony success? Is the total number of cells per nest related to the number of adults produced? The study was conducted in Juiz de Fora, southeastern Brazil, from December 2006 to November 2007. Nesting in man-made substrata seems to be a common strategy in M. cassununga (90.9%), with preference for nest building with a horizontal comb facing north. The colonies were established mainly by groups of foundresses (67.6%), with a success of 84%. The number of brood cells produced per nest was 71.74 ± 45.25 (18-203), and it was positively correlated with the number of adults produced. Hence, we can say that the nests founded by M. cassununga are located mainly in man-made substrata and mostly founded by a group of females. The cell reuse behavior increases the number of adults produced, as it optimizes foraging. These characteristics together with its behavior and nesting habits promote the success of this species in thriving in urban environments.

We captured foragers of the tropical social wasp Ropalidia marginata from their nests and displaced them at different distances and directions. Wasps displaced within their probable foraging grounds returned to their nests on the day of release although they oriented randomly upon release; however, wasps fed before release returned sooner, displaying nest-ward orientation. When displaced to places far from their nests, thus expected to be unfamiliar, only a third returned on the day of release showing nest-ward orientation; others oriented randomly and either returned on subsequent days or never. When confined within mosquito-net tents since eclosion and later released to places close to their nests (but unfamiliar), even fed wasps oriented randomly, and only older wasps returned, taking longer time. Thus, contrary to insects inhabiting less-featured landscapes, R. marginata foragers appear to have thorough familiarity with their foraging grounds that enables them to orient and home efficiently after passive displacement. Their initial orientation is, however, determined by an interaction of the information acquired from surrounding landscape and their physiological motivation. With age, they develop skills to home from unfamiliar places. Homing behaviour in insects appears to be influenced by evolutionarily conserved mechanisms and the landscape in which they have evolved. [ABSTRACT FROM AUTHOR]

Parasites can manipulate host behaviour to increase their own transmission and fitness, but the genomic mechanisms by which parasites manipulate hosts are not well understood. We investigated the relationship between the social paper wasp, Polistes dominula, and its parasite, Xenos vesparum (Insecta: Strepsiptera), to understand the effects of an obligate endoparasitoid on its host's brain transcriptome. Previous research suggests that X. vesparum shifts aspects of host social caste-related behaviour and physiology in ways that benefit the parasitoid.We hypothesized that X. vesparum-infested (stylopized) femaleswould showa shift in caste-related brain gene expression. Specifically, we predicted that stylopized females,whowould normally beworkers,would show gene expression patterns resembling pre-overwintering queens (gynes), reflecting gyne-like changes in behaviour. We used RNA-sequencing data to characterize patterns of brain gene expression in stylopized females and compared these with those of unstylopized workers and gynes. In support of our hypothesis, we found that stylopized females, despite sharing numerous physiological and life-history characteristics with members of the worker caste, show gyne-shifted brain expression patterns. These data suggest that the parasitoid affects its host by exploiting phenotypic plasticity related to social caste, thus shifting naturally occurring social behaviour in a way that is beneficial to the parasitoid. [ABSTRACT FROM AUTHOR]