Social Wasps Research Articles

Metabolomics analysis of larval secretions reveals a caste-driven nutritional shift in a social wasp colony

Social wasps exhibit a unique nutritional cycle in which adults feed larvae with prey, and larvae provide adults with larval secretions (LS). LS serves as a vital nutritional source for adults, contributing to the colony’s health and reproductive success. The LS nutrient composition has been previously reported in various wasp species, yet these analyses focused solely on worker-destined larvae, overlooking the potential caste designation effects on LS composition.Using metabolomics techniques, we analysed and compared the metabolite and nutrient composition in LS of queen- and worker-destined larvae of the Oriental hornet. We found that queen-destined LS (QLS) contain greater amounts of most metabolites, including amino acids, and smaller amounts of sugars compared to worker-destined LS (WLS). The amino acid-to-sugar ratio in QLS was approximately tenfold higher than in WLS. Thus, as the colony transitions from the production of workers to the production of reproductives, it gradually experiences a nutritional shift that may influence the behaviour and physiology of the adult nest population. This caste-specific metabolite profile and nutrient composition of LS reflect the differences in the diet and physiological requirements of worker- and queen-destined larvae and may play a critical role in caste determination in social wasps.

Catch and release: controlling eastern yellowjacket Vespula maculifrons colonies using horizontal insecticide transfer.

Horizontal insecticide transfer is thought to play an important role in controlling a wide range of urban pests including ants, bed bugs, cockroaches and termites. Trap-treat-release is an effective experimental approach that has been used to successfully manage populations of invasive ants in field applications. Trap-treat-release is based on the principles of horizontal transfer. Individuals are captured, treated with the toxicant and released back into the environment. The treated individuals then return to the colony and transfer the toxicant to other members of the population resulting in secondary mortality. The goal of the current study was to evaluate the efficacy of the trap-treat-release technique for controlling field populations of the eastern yellowjacket, Vespula maculifrons. Laboratory experiments demonstrated that fipronil was highly toxic against V. maculifrons across a wide range of concentrations. Furthermore, fipronil was efficiently transferred from treated donors to untreated recipients and caused significant secondary mortality. A field experiment utilized trap-treat-release and demonstrated that fipronil was effectively transferred when foraging worker wasps are trapped, treated, released and allowed to return to their respective colonies. The trap-treat-release method may be an effective alternative to direct nest treatments and could help alleviate problems such as insecticide runoff, environmental contamination, and non-target effects. This method has the potential to provide effective management of social wasps. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Investigating the Influence of Varied Light-Emitting Diode (LED) Wavelengths on Phototactic Behavior and Opsin Genes in Vespinae

The phototactic behavior of insects is commonly used to manage pest populations in practical production. However, this elusive behavior is not yet fully understood. Investigating whether the opsin genes play a crucial role in phototaxis is an intriguing topic. Vespinae (Hymenoptera: Vespidae) are a common group of social wasps that are closely associated with human activities. Efficiently controlling wasp populations while maintaining ecological balance is a pressing global challenge that still has to be resolved. This research aims to explore the phototactic behavior and key opsin genes associated with Vespinae. We found significant differences in the photophilic rates of Vespula germanica and Vespa analis under 14 different light conditions, indicating that their phototactic behavior is rhythmic. The results also showed that the two species exhibited varying photophilic rates under different wavelengths of light, suggesting that light wavelength significantly affects their phototactic behavior. Additionally, the opsin genes of the most aggressive hornet, Vespa basalis, have been sequenced. There are only two opsin genes, one for UV light and the other for blue light, and Vespa basalis lacks long-wavelength visual proteins. However, they exhibit peak phototaxis for long-wavelength light and instead have the lowest phototaxis for UV light. This suggests that the visual protein genes have a complex regulatory mechanism for phototactic behavior in Vespinae. Additionally, visual protein sequences have a high degree of homology among Hymenoptera. Despite the hypotheses put forward by some scholars regarding phototaxis, a clear and complete explanation of insect phototaxis is still lacking to date. Our findings provide a strong theoretical basis for further investigation of visual expression patterns and phototactic mechanisms in Vespinae.

Si no puedes soportar el calor, ¡sal de la cocina! Notas sobre la influencia de la temperatura en el anidamiento de avispas sociales

For social wasps, the selection of the nesting substrate represents the success or failure of the colony, and temperature is a determining factor for this selection. With the increase in global temperature due to climate change, it is essential to understand how temperature actually interferes in the selection of the foundation site of social wasp colonies. Here, we describe a curious nest founding strategy on a rocky outcrop in the state of Minas Gerais, Brazil. Social wasps selected the lighter areas of the outcrop where they had greater success in developing their colonies. These lighter areas absorb less heat and had a lower average temperature when compared to darker areas.

When the predator becomes the prey: record of Mischocyttarus rotundicollis (Cameron, 1912) (Hymenoptera: Vespidae) feeding on a spider in southeastern Brazil

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.

Taxonomic notes on the Zethus olmecus de Saussure, 1875 species group (Hymenoptera, Vespidae, Eumeninae), with the description of five new species

Zethus Fabricius is the largest genus within Vespidae with nearly 300 species. The genus has a central role on discussion of social evolution, once some species share behavioral features between solitary and social representatives of vespids and the genus has been recovered as phylogenetically closer to social wasps than to other Eumeninae. The Zethus olmecus species group is even more remarkable since there are observations of communal nesting behavior, a fact misused as support for the hypothesis of closer relationship to social wasps. Herein we closely investigate the taxonomy of this group of species, the first step needed for future studies to properly approach its evolution. The taxonomic approach involved examination of external morphology and male genitalia. Five new species are described for the group: Z. bolivari n. sp., Z. hermesi n. sp., Z. hexacirratus n. sp., Z. perilloi n. sp., and Z. utingensis n. sp. The unknown female of Z. peruvicus is also described. An illustrated taxonomic key is presented. Geographical distribution is expanded for Z. peruvicus, Z. pygmaeus, Z. thoracicus, and Z. toltecus. Finally, additional notes and corrections of existing literature are given.

Anticoagulant properties and therapeutic potentials of wasp venom

AbstractWasp venom is rich in bioactive substances, such as proteins, peptides, and small molecules. The venom significantly affects the mammalian cardiovascular, nervous, and immune systems, causing mild to severe symptoms following stings. It exhibits both procoagulant and anticoagulant activities, and significant research has identified its ability to modulate the mammalian coagulation system. Active substances that inhibit clotting have been identified and purified through patient case reports and experimental studies. This study reviewed the findings on how wasp venom interacts with platelets and coagulation factors, such as fibrinogen and prothrombin, and demonstrated its dual influence on the coagulation cascade. This highlights the potential of the venom in therapeutic applications, especially as an anticoagulant, as evidenced by the inhibition of coagulation factors and prolonged clotting times after envenomation, suggesting its utility in developing novel anticoagulant therapies. This review focuses on the anticoagulant effects of social wasp venom, which is prevalent in sting incidents, summarizing the research and observations on its therapeutic potential. This emphasizes the significance of further studies to identify and utilize venom components as innovative anticoagulant treatments.

Daños causados por avispas sociales (Hymenoptera: Vespidae) a frutos comerciales en la región amazónica brasileña

Social wasps play a crucial role in ecosystems by actively foraging and preying on lepidopterans caterpillars, an important group of insects known to damage various structures of cultivated plants. However, there is a discussion about the potential damage that these wasps can cause to the fruits of some commercial species. In this research, cases of damage caused by Polybia dimidiata (Olivier), Polybia liliacea (Fabricius), Synoeca surinama (Linnaeus), and Synoeca virginea (Fabricius) to fruits of three different fruit species: guava, carambola, and murici, are recorded while they are still attached to the stem. These events occurred in the municipalities of Itacoatiara and Uarini, both located in the state of Amazonas, northern Brazil. These observations were made in the months of January 2013, December 2022, January, and February 2023. Due to their high infestation and vigorous foraging activities, it is speculated we posit that these wasp species could reach pest status, affecting the fruit harvests by stinging workers and damaging the fruits until made for marketing. However, it is crucial to emphasize that more comprehensive studies are needed to determine whether the damage caused by these vespids really represents a threat to small farmers.

Temperature differently affects body pigmentation of the paper wasp Polistes dominula along an urban and a wider geographical gradient

In insects, different pigments, such as melanins and pterins, are involved in thermoregulation. The degree of melanisation often varies along geographical gradients, according to the so-called thermal melanism hypothesis, i.e. darker forms are found in colder places because they can warm up more quickly. Similarly, pterins work as heat sinks and thus are expected to be more abundant in colder sites. Cities, which are warmer than surrounding areas (Urban Heat Island (UHI) effect), might also be expected to influence pigmentation, although studies are lacking. Here, we sampled workers of the social paper wasp Polistes dominula (Christ, 1791) (Vespidae) across an urbanisation gradient in an Italian metropolis and used iNaturalist pictures of this species across Italy to study pigmentation patterns at both urban and larger geographical scales. We found a lower yellow intensity of abdominal spots at warmer locations. Scanning Electron Microscopy strongly suggested that yellow colouration is due xanthopterin, known to be the heat sink molecule in other social vespids. Thus, wasps from warmer (i.e., urban) environments are likely to have fewer xanthopterin granules, in line with the lack of need for heat storage due to the local thermal gradient (UHI effect). At the country level, we found that wasps at higher latitudes had smaller yellow spots on the thorax and only two spots instead of four at higher altitudes, in full accordance with the thermal melanism hypothesis. In conclusion, climatic conditions seem to affect insect colour patterns both along urban and wider geographical gradients, although colour changes may affect different body parts and pigments likely according to different needs.

Proposed vacuum sampling method for collecting foraging Vespula wasps at their nest entrance

AbstractSampling nests of yellow jackets, Vespula spp. (Hymenoptera: Vespidae), represent a particular challenge due to the danger involved in working with live colonies of a potentially aggressive venomous super‐organism. Here, we report on sampling methods using a petrol‐driven leaf blower/vacuum and a battery‐powered vacuum to sample returning Vespula germanica (Fabricius) foragers at their nest entrance. These methods make the sampling of returning foragers at the nest more efficient and convenient and represent a low‐risk approach to sampling. Applications include prey analysis and genetic sampling that can be done destructively or non‐destructively depending on the geographic location. We sampled 15 nests using the two‐stroke vacuum apparatus and collected on average (±SD) 454 ± 271 wasps per nest. We believe that the petrol‐driven vacuum collection apparatus we designed is a useful method for collecting a large number of social wasp foragers returning to a single‐nest entrance.

Molecular Characterization and Phylogenetic Analysis of Flightin Gene in Vespa basalis (Hymenoptera, Vespidae).

Flight is a complex physiological process requiring precise coordination of muscular contraction. A key protein in insect flight is flightin, which plays an integral role in the flight muscles. This research sought to evaluate the flight competence of the social wasp V. basalis by characterizing the molecular components involved. Our study focused on Vespa basalis, one of the most dangerous hornet species, utilizing PCR to obtain a partial cDNA sequence of the flightin protein. We then employed phylogenetic and sequence analysis to gain insights into this protein in flight-related adaptations. The cDNA has an 1189-base pair sequence including an open reading frame (453 bp) encoding 150 amino acids. Analyzing the deduced amino acid sequence using an online tool revealed a molecular weight of 18.05 kDa, an isoelectric point of 5.84, four functional site patterns, and no transmembrane topology. We constructed a phylogenetic tree of flightin based on 38 species. Our analysis indicated that V. basalis is most closely related to V. mandarinia; this alignment is consistent with their similar aggressive behavior, but their evolutionary relationship, based on mitochondrial sequences, presents a contrast. These initial findings on the flightin gene in V. basalis lay the groundwork for future functional studies to elucidate its specific role in flight adaptations and explore its potential as a target for pest management strategies.

A mixture of mesotrione and atrazine harms adults and larvae of the predatory wasp Polistes satan

Herbicides have been intensively used for weed control, raising concerns about their potentially adverse effects on non-target organisms. Research on the effects of these common agrochemicals on beneficial insects and the ecosystem services they provide (e.g., predation and pollination) is scarce. Therefore, we tested whether a commercial formulation comprising a mixture of mesotrione and atrazine was detrimental to adult females and larvae of the Neotropical predatory social wasp Polistes satan, which is an effective natural enemy of crop pests. Wasps were individually fed syrups contaminated with different concentrations of the herbicide above and below the maximum label rate (MLR = 12 mL/L). Survival was assessed. The locomotor activity, immune response, and midgut morphology of adults as well as the immune response of the larvae were also studied. Herbicide concentrations far above the MLR (12, 40, and 100 times) caused adult mortality, whereas lower concentrations (0.5, 1, and 6 times) did not. Herbicide exposure at 0.5 to 12 times the MLR increased adult activity. Adult exposure at 0.1 or 0.5 times the MLR did not affect melanotic encapsulation of foreign bodies but led to changes in the morphology of the midgut epithelium and peritrophic matrix. In larvae, the ingestion of herbicide at 0.1 or 0.2 times the MLR (corresponding to 9.6 and 19.2 ng of herbicide per individual) did not cause mortality but decreased their melanization-encapsulation response. Increased locomotor activity in herbicide-exposed adults can affect their foraging activity. The altered midgut morphology of adults coupled with the decreased immune response in larvae caused by herbicide exposure at realistic concentrations can increase the susceptibility of wasps to infections. Therefore, herbicides are toxic to predatory wasps.

Adaptive significance of early reproduction in Vespula shidai social wasps

Adaptive significance of early reproduction in Vespula shidai social wasps

SYNTHESIS AND BIOLOGICAL COMPARISON OF TWO ANTIMICROBIAL PEPTIDES ORIGINATED FROM THE VENOM OF VESPA CRABRO AND POLYBIA PAULISTA

Bee venom is abundant in potential antimicrobial peptides, AMPs, . Among them, Mastoparan C and Polybia-MP1 are two well-known AMPs that were found in the European Hornet Vespa crabro and social wasp Polybia paulista, respectively. Due to the potent antimicrobial activity toward a wide range of microbial pathogens, including Gram-negative, Gram-positive and fungal species, they are promising to tackle the global antimicrobial resistance crisis. Thus, understanding the structure and activity relationships (SARs) is essential for the development of potential therapeutic applications. In this study, we synthesized and compared the differences in biological properties of these two antimicrobial peptides. The preliminary data suggests various important information regarding the structural requirements for optimizing the pharmacological properties of antimicrobial peptides.

Taxonomic account and phylogenetic relationships of the species of the Neotropical social wasp genus Chartergus Lepeletier, 1836 (Vespidae: Polistinae: Epiponini).

The Neotropical social wasp genus Chartergus is reviewed and comparative diagnoses, images of type material, and an updated identification key for species are presented. To investigate the phylogenetic relationships within the genus, we used a combined dataset of morphological characters, nest architecture traits, and molecular data. The results revealed the following relationships among the Chartergus species: (C. globiventris + (C. artifex + C. metanotalis)).

Novel insights into paternity skew in a polyandrous social wasp.

Females of many species are polyandrous. However, polyandry can give rise to conflict among individuals within families. We examined the level of polyandry and paternity skew in the common eastern yellowjacket wasp, Vespula maculifrons, in order to gain a greater understanding of conflict in social insects. We collected 10 colonies of V. maculifrons and genotyped workers and prereproductive queens at highly variable microsatellite markers to assign each to a patriline. Genotypic data revealed evidence of significant paternity skew among patrilines. In addition, we found that patrilines contributed differentially to caste production (worker vs. queen), suggesting an important role for reproductive conflict not previously discovered. We also investigated if patterns of paternity skew and mate number varied over time. However, we found no evidence of changes in levels of polyandry when compared to historical data dating back almost 40years. Finally, we measured a suite of morphological traits in individuals from the most common and least common patrilines in each colony to test if males that showed highly skewed reproductive success also produced offspring that differed in phenotype. Our data revealed weak correlation between paternity skew and morphological phenotype of offspring sired by different males, suggesting no evidence of evolutionary tradeoffs at the level investigated. Overall, this study is the first to report significant paternity and caste-associated skew in V. maculifrons, and to investigate the phenotypic consequences of skew in a social wasp. Our results suggest that polyandry can have important consequences on the genetic and social structure of insect societies.

Social wasps (Vespidae: Polistinae) harvesting food bodies of Cecropia Loefl. (Urticaceae) in Central Amazon

Social wasps are among the most curious non-ant insects known to harvest food bodies of Cecropia Loefl. The aim of this note is to describe for the first time: (1) interactions between wasp species which harvest food bodies; (2) interactions of these wasps with other insects associated to Cecropia (ants, assassin bugs); (3) the use of a food resource different from müllerian bodies; and (4) wasp species whose association with Cecropia was unknown until now. All records were made in Manaus region and in Uatumã Sustainable Development Reserve (Amazonas State, Brazil), with the aid of a digital camera. The wasp and ant species involved were captured for later identification. The recorded wasp species were: Charterginus xanthura Saussure, 1854, Protopolybia chartergoides Gribodo, 1891, Protopolybia minutissima Spinola, 1851, and Synoeca virginea Fabricius, 1804 (Hymenoptera: Vespidae). The findings corroborate the importance of food bodies not only for Azteca Forel, 1878 ants, but also for other social insects.

Overlooked and misunderstood: how urban community gardeners perceive social wasps and their ecosystem functions

Despite their importance for agricultural food production, many insects receive little to no positive attention. While bees have become the focus of insect conservation in agricultural landscapes, social wasps still rank among the most disliked animals and their ecological role and the ecosystem services they provide through e.g. pollination and pest control is subsequently understudied. We conducted a survey on the perceptions of social wasps and their ecosystem functions in urban community gardens in Berlin and Munich, Germany. We found that gardeners rated wasps as least beneficial for urban gardens among other insect taxa, and that predation was perceived as a negative function in insects and spiders. Respondent´s emotions were predominantly positive towards bees and negative towards wasps. Trivia questions about wasps revealed that knowledge of wasp ecology was positively associated with respondents´ willingness to share gardens with wasps. Implications for insect conservation: Our results show that urban gardeners´ negative perceptions of social wasps are likely driven by both a lack of knowledge about their ecological functions and a profusion of negative emotions towards wasps. Public outreach and education on the ecological importance of social wasps and other uncharismatic taxa as well as positive encounters with these specieshave the potential to improve their public image and thereby support the conservation of wasps and other insects.

Conventional cytogenetics and microsatellite chromosomal distribution in social wasp Mischocyttarus cassununga (Ihering, 1903) (Vespidae, Polistinae, Mischocyttarini).

Cytogenetics has allowed the investigation of chromosomal diversity and repetitive genomic content in wasps. In this study, we characterized the karyotype of the social wasp Mischocyttarus cassununga using conventional cytogenetics and chromosomal mapping of repetitive sequences. This study was undertaken to extend our understanding of the genomic organization of repetitive DNA in social wasps and is the first molecular cytogenetic insight into the genus Mischocyttarus. The karyotype of M.cassununga had a chromosome number of 2n=64 for females and n=32 for males. Constitutive heterochromatin exhibited three distribution patterns: centromeric and pericentromeric regions along the smaller arms and extending almost the entire chromosome. The major ribosomal DNA sites were located on chromosome pair in females and one chromosome in males. Positive signals for the microsatellite probes (GA)n and (GAG)n were observed in the euchromatic regions of all chromosomes. The microsatellites, (CGG)n, (TAT)n, (TTAGG)n, and (TCAGG)n were not observed in any region of the chromosomes. Our results contrast with those previously obtained for Polybia fastidiosuscula, which showed that the microsatellites (GAG)n, (CGG)n, (TAT)n, (TTAGG)n, and (TCAGG)n are located predominantly in constitutive heterochromatin. This suggests variations in the diversity and chromosomal organization of repetitive sequences in the genomes of social wasps.

Worker trapping: a sustainable management tool for invasive social wasps?

The invasive social wasp Vespula germanica is a harmful pest, mainly in urban environments. Despite extensive research on ecology and control, there are currently no effective, sustainable strategies to manage populations in the invaded range. We evaluated the effects of worker trapping on V. germanica abundance and nest activity in Southern Argentina. During two consecutive years, a high-density trapping was deployed in four plots of one hectare each. The procedure consisted of placing 25 non-toxic meat-baited traps, creating a grid of 5 × 5 traps for 4 weeks. Worker wasp abundance and the traffic rate of all the nests in the plots were measured 1 week before and one after trapping. Our results showed that worker catches resulted in a 65% reduction in local wasp abundance and a 48% in traffic rate of nests within the treated area. Similarly, a decrease in wasp abundance was obtained one year after trapping. Employing worker trapping as a tool could prove useful and environmentally friendly in reducing local wasp abundance during peak activity.