Vespa Velutina Research Articles

Microscopic Identification of Anatomical Elements and Chemical Analysis of Secondary Nests of Vespa velutina nigrithorax du Buyson.

Simple SummaryVespa velutina nigrithorax, one of the eleven subspecies of Vespa velutina, has become a matter of concern due to its invasive behavior after its accidental introduction into France in 2004. This Vespa species, also known as the yellow-legged hornet, builds large nests, the structure and chemical composition of which are of interest to know and understand in order to estimate the areas that these hornets may find acceptable for establishing new colonies. Its presence causes serious negative impacts on ecosystems and on pollinating species, especially on honeybees. As the presence of this type of hornet is very recent in Europe, there are large gaps in our knowledge about its adaptability and control measures. The main objective of this study is to identify the composition of the materials used by the Asian hornet in the construction of secondary nest envelopes. The samples that were collected from each nest were analyzed using two microscopic devices in non-disaggregated and disaggregated material. The same samples were also chemically analyzed by means of X-ray diffraction and SEM/EDS (scanning electron microscopy). It was noticed that the nests were formed by the agglomeration of small particles that are spatially organized in brown and beige strips. The microscopic analysis showed the presence of cellular elements of agricultural origin, woody material from forest species, and leaves, almost all of which were lignocellulose materials. The results achieved from chemical analysis led to the conclusion that the main chemical constituent of the nests is cellulose. As for the elemental analysis, about 99% of the nests were composed of C and O and low amounts of other microelements (Na, Al, Si, K, and Ca).Vespa velutina accidentally arrived in Europe (France) in 2004, and rapidly expanded throughout the entire country. Its presence in mainland Portugal was first noticed in 2011. Being an invasive species with no natural predators in the region to control it, it has caused enormous environmental and economic damage, particularly on Apis mellifera (honeybee) colonies. Although there is already some research on this species’ biology, little is known about its adaption to European ecological conditions, specifically in terms of nest building. This type of hornet builds a primary nest in the spring to start a colony. During the summer, they build a secondary nest to develop the main colony. These secondary nests are ovoid-shaped and range in size from 18.7 cm to 45.0 cm in diameter and from 19.2 cm to 65.0 cm in length, attaining their highest development in late summer. The external appearance of these nests is characterized by alternating stripes that are beige and brown in color. The main objective of this study is to identify the composition and the origin of the materials that are used by Vespa velutina nigrithorax to build the outer envelope of these secondary nests. This information could be very interesting and will not only increase our knowledge on the biology of the species in regions far from its original area, but will also be relevant for the future implementation of new policies to control this invasive species by means biological control. Several samples were taken from each nest and were observed under different optical magnifying devices. In the second stage, their chemical composition was analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM/EDS). It was noticed that almost all of the materials used in the nests’ construction were lignocellulose from woody materials from both softwood (gymnosperm) and hardwood (angiosperm) forest species as well from leaves and small particles of agricultural origin (grasses). The beige strips were formed almost exclusively from woody softwood cells, while the brown strips were composed of hardwood cells, leaf tissues, and grasses. Chemically, it was noticed that this material mainly consisted of cellulose, with more than 99% being composed of C and O and very little mineral material from elements such as Na, Al, Si, K, and Ca. The achieved results allow us to state that in the construction of these secondary nests, these hornets only used organic materials that are then probably agglomerated through their mouths.

Combining surveys and on-line searching volumes to analyze public awareness about invasive alien species: a case study with the invasive Asian yellow-legged hornet (Vespa velutina) in Italy

The Asian yellow-legged hornet (Vespa velutina) has been invading Italy since 2013, and it was subjected to management programs to counter its spread and raise awareness about its impacts. We administered a questionnaire to a sample of 358 beekeepers in Italy, asking them about their sources of information on V. velutina and their perception of its potential impacts and severity, compared to other threats to beekeeping. We also explored Internet searching volumes on Google and Wikipedia about V. velutina, to identify seasonal and long-term trends in public awareness. Workshops, journals or bulletins, the Internet and word-of-mouth with colleagues were the primary sources of information about V. velutina. Internet searches peaked during the activity period of the species and increased over time, with thousands of visits to Wikipedia each month. Beekeepers believed V. velutina to affect beekeeping by predating on honey bees (Apis mellifera), paralyzing foraging, reducing honey availability and depleting the winter cluster. Moreover, V. velutina has been deemed a severe threat to beekeeping, similar to other threats like pesticides and the varroa mite (Varroa destructor). Our findings indicate that beekeepers seem to be aware of the potential impacts of V. velutina in Italy, both within and outside of its invaded area, considering it a major threat to beekeeping. Moreover, citizens seem to have become progressively curious about the species. Information campaigns on the Internet and specialized magazines might be helpful to communicate about the impacts of the species, and the need to develop diffused surveillance networks.

Contrasting patterns from two invasion fronts suggest a niche shift of an invasive predator of native bees.

BackgroundThe accuracy of predictions of invasive species ranges is dependent on niche similarity between invasive and native populations and on our ability to identify the niche characteristics. With this work we aimed to compare the niche dynamics of two genetically related invasive populations of Vespa velutina (an effective predator of honeybees and wild pollinators), in two distinct climatic regions, one in central Europe and another one in the north-western Iberian Peninsula, and hence to identify uninvaded regions susceptible to invasion.MethodsNiche dynamics and shifts of V. velutina were assessed by comparing the environmental niches of the native and of the two invasive populations, using climatic, topographic and land use variables. We also ran reciprocal distribution models using different algorithms and records from both native and invasive ranges to compare model predictions and estimate which regions are at a greater risk of being invaded.ResultsAn apparent niche shift was detected in the population of the NW of Iberian Peninsula, where the species is living under environmental conditions different from the native niche. In central Europe, large suitable areas remain unoccupied. The fact that both invasive populations are well established, despite occupying environmentally distinct regions indicates that V. velutina has a high ability to successfully invade different environmental envelopes from those existing in its native range. For example, in north-western Iberian Peninsula the species is now thriving out of its native niche limits. Moreover, the large extent of still unoccupied environmental space with similar conditions to those used by the species in its native range suggests that there is still a large area of central and eastern Europe that can be potentially invaded by the species.

Wasp Venom Relieves Alzheimer's Phenotypes in 5xFAD Transgenic Mice through Inhibition of Aβ Aggregation

Alzheimer’s disease (AD), a neurodegenerative disorder, has been known to be mostly commonly diagnosed in people over the age of 65. However, there is no drug that can cure AD. This study aimed to investigate if wasp venom (WV) can mitigate phenotypes of AD using a 5xFAD transgenic mouse model. The mice were administered intraperitoneally with WV obtained from Vespa velutina at a concentration of 250 or 400 μg/kg body weight (BW) once a week for a total of 14 weeks. WV treatment was shown to alleviate memory impairments in 5xFAD mice in behavioral tasks, including passive avoidance, Y‐maze and Morris water maze tests. In addition, we found that WV treatment decreased the level of 8‐hydroxy‐2′‐deoxyguanosine, a biomarker of oxidative DNA damage, in mouse plasma and the level of malondialdehyde, an indicative of lipid peroxidation, in liver and cerebral cortex, indicating that WV prevents oxidative damage. In particular, WV treatment increased expression of antioxidant‐associated proteins, a nuclear factor erythroid‐derived 2‐related factor 2 (Nrf2) and heme oxygenase‐1 (HO‐1), in the cerebral cortex and decreased inflammation‐associated protein, cyclooxygenase‐2 (COX‐2), amyloid beta (Aβ) plaque‐associated proteins, C‐terminal fragment (C99), and beta‐site amyloid precursor protein cleaving enzyme 1 (BACE1, β‐secretase) in the hippocampal tissue homogenates. Furthermore, we confirmed that WV treatment reduced the accumulation of Aβ plaque in the hippocampal area via thioflavin S staining. Taken together, these findings suggest that WV could ameliorate AD symptoms and delay AD onset and progression.

Consistency of Determination of sIgE and the Basophil Activation Test in Vespa velutina nigrithorax Allergy.

Consistency of Determination of sIgE and the Basophil Activation Test in Vespa velutina nigrithorax Allergy.

Monitoring Study in Honeybee Colonies Stressed by the Invasive Hornet Vespa velutina.

Vespa velutina is an invasive species that is currently the main concern for beekeeping in some areas of northern Spain. The hornet hunts honeybees to feed its larvae, stressing and weakening the honeybee colonies. To avoid losses of honeybee colonies, it is essential to investigate the pressure that is exerted by the yellow-legged hornet on apiaries and its consequences. In the present study, hives were monitored in an apiary that was situated in a high-pressure area of V. velutina during the years 2020 and 2021. The monitoring of environmental conditions of the apiary, the internal conditions of the colonies, and a hunting camera were used to relate the presence of hornets in front of the hives to the weather conditions in the apiary and the consequences caused on the colonies. The relationships between weather conditions and the hornet’s activity showed two types of hornet behavior. In the months of July and August, the maximum number of hornets appeared in non-central hours of the day. Meanwhile, in the months of September and October, the highest pressure in the apiary occurred in the central hours of the day, coinciding with temperatures between 15 °C and 25 °C and a relative humidity that was higher than 60%. The honeybee colony with the highest thermoregulatory capacity was the strongest and it was the key factor for the colony survival even when the hornet pressure was high too. Therefore, strengthening the hives and improving beehive health status is essential to avoid colonies decline.

Wasp Venom Ameliorates Scopolamine-Induced Learning and Memory Impairment in Mice.

This study investigated the effects of wasp venom (WV) from the yellow-legged hornet, Vespa velutina, on scopolamine (SCO)-induced memory deficits in mice, as well as the antioxidant activity in HT22 murine hippocampal neuronal cells in parallel comparison with bee venom (BV). The WV was collected from the venom sac, freeze-dried. Both venoms exhibited free radical scavenging capabilities in a concentration-dependent manner. In addition, the venom treatment enhanced cell viability at the concentrations of ≤40 µg/mL of WV and ≤4 µg/mL of BV in glutamate-treated HT22 cells, and increased the transcriptional activity of the antioxidant response element (ARE), a cis-acting enhancer which regulates the expression of nuclear factor erythroid 2-related factor 2 (Nrf2)-downstream antioxidant enzymes. Concurrently, WV at 20 µg/mL significantly increased the expression of a key antioxidant enzyme heme oxygenase 1 (HO-1) in HT22 cells despite no significant changes observed in the nuclear level of Nrf2. Furthermore, the intraperitoneal administration of WV to SCO-treated mice at doses ranged from 250 to 500 µg/kg body weight ameliorated memory impairment behavior, reduced histological injury in the hippocampal region, and reduced oxidative stress biomarkers in the brain and blood of SCO-treated mice. Our findings demonstrate that WV possess the potential to improve learning and memory deficit in vivo while further study is needed for the proper dose and safety measures and clinical effectiveness.

Correction to: Invasion genetics of the Asian hornet Vespa velutina nigrithorax in Southern Europe

Correction to: Invasion genetics of the Asian hornet Vespa velutina nigrithorax in Southern Europe

Using Maximum Entropy Algorithm to Analyze Current and Future Distribution of the Asian hornet, Vespa velutina, in Europe and North Africa Under Climate Change Conditions

Using Maximum Entropy Algorithm to Analyze Current and Future Distribution of the Asian hornet, Vespa velutina, in Europe and North Africa Under Climate Change Conditions

Genetic and morphological variation of Vespa velutina nigrithorax which is an invasive species in a mountainous area

The yellow-legged hornet (Vespa velutina nigrithorax) is an invasive species in South Korea with negative economic, ecological, and public health impacts. We investigated genetic and morphological variation in the species populations on Mt. Jiri, the tallest mountain in South Korea. We hypothesized that a high-altitude would be negatively correlated with the genetic diversity of the hornet population, and hornet wing morphology would change with an increase in altitude. Our results showed that the genetic diversity of yellow-legged hornets did not decrease as altitude increased. Regardless of the altitude, the inbreeding coefficient was high at the newly colonized sites. A single genetic population occurred in the mountainous areas examined and gradually expanded its range. Wing morphology, especially shape, did not change with an increase in altitude or decrease in temperature. Although snow cover and cool temperatures at high altitudes could limit nest-building activities, they did not prevent the extension of the range of the species. Therefore, the yellow-legged hornet cannot be controlled naturally by climate or topography; combined approaches, including chemical control, nest removal, and bait-trapping techniques should be implemented.

Ensemble of small models as a tool for alien invasive species management planning: evaluation of Vespa velutina (Hymenoptera: Vespidae) under Mediterranean island conditions

Ecological niche models have proved to be a powerful tool in assessing invasiveness risk of alien species, allowing the optimization of control strategies. Vespa velutina (Hymenoptera: Vespidae) is an invasive species with strong ecological, economical and health impacts in Europe after it was first reported in France in 2004. It was detected for the first time on a Mediterranean island (Mallorca, Balearic Islands, Spain) in 2015, where a single nest was found in the northwest of the island. Immediately, a control plan was implemented. In this study, we analysed 30 occurrence data in Mallorca island to assess the suitability distribution predicted for Mediterranean island conditions using an ensemble of small models. We obtained high values of AUC (0.9165), Somers’ D (0.8331), Boyce (0.7611) and TSS (0.7754) as quality parameters of the final ensembled model. We show for the first time that there are suitable areas where this species can expand and stablish, mainly in steeper slopes and low isothermality zones. Likewise, the distribution suitability of V. velutina for other Mediterranean islands (Ibiza, Formentera, Menorca, Corsica, Sardinia, Sicily, Crete and Cyprus) was also explored, showing potentially suitable zones. This study provides valuable information regarding the areas in the Mediterranean islands under risk of invasion, and it could be used by both scientists and managers for an early detection and control of the invasive species due to its cost-effectiveness in terms of conservation.

Dipeptidyl peptidase IV of the Vespa velutina nigrithorax venom is recognized as a relevant allergen

BackgroundVespa velutina nigrithorax (VVN), typically known as the Asian yellow-legged wasp, has been one of the most significant invasive species in western Europe since 2010. Currently, VVN has become the most prevalent cause of Hymenoptera anaphylaxis in the north and northwestern Spain. For this reason, it is crucial to diagnose anaphylaxis cases in the acute moment for carrying out the best available treatment as soon as possible. ObjectiveTo achieve a complete understanding of the venom allergen composition that will help to develop efficient diagnostics and immunotherapy treatments on the basis of this venom. MethodsIn this study, autochthonous VVN venom was obtained and characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing, followed by a mass spectrometry analysis. In addition, the allergenic sensitization profile of patients diagnosed with allergy to VVN in the Allergology Service of Navarra University Hospital between the years 2017 and 2020 was studied by immunoblotting and specific IgE (ImmunoCAP, Thermo Fisher Scientific, Uppsala, Sweden). ResultsTwo new allergens (dipeptidyl peptidase IV and serin protease) were identified in the autochthonous VVN venom, and their identity was confirmed by liquid chromatography–mass spectrometry analysis. The study by ImmunoCAP using sera from 12 patients who had a systemic reaction after a VVN sting revealed groups 5 and 1 as predominant allergens (92% and 34%, respectively). Furthermore, the immunoblotting assay recognized dipeptidyl peptidase IV (50%) in the sera of these patients. ConclusionSerine protease and the dipeptidyl peptidase IV are components of the VVN venom, and the latter is an allergen recognized in the studied population.

Social wasps in Spain: the who and where.

The objective of this study was to list the social vespids occurring in Spain, determine their presence in each region, and correlate the data with the vespids responsible for allergic reactions and their progression over time. Insects distribution data were collected in two phases: from the southern half of Spain (2008-2012), and from the northern half of Spain (2016-2019). Data for the vespids were collected from the prescriptions of Hymenoptera venom immunotherapy (HVIT) at six Spanish hospitals in the years 2009 and 2019. Polistes dominula and Vespula germanica were the most widely distributed species. Vespa velutina was found to be present in a large part of northern Spain. During the 10 year period, the prescriptions of vespid VIT increased by 42.63%. The north of Spain saw a 3.61 fold greater predominance of prescriptions for Vespula (to some extent influenced by Vespa velutina allergy) whereas in central and southern Spain, there was a 3.97 fold greater predominance of prescriptions for Polistes. It is the first study that compares the vespid distribution maps with VIT prescription. A noteworthy finding is the wide presence of Polistes dominula and Vespula germanica in Spain and the appearance of Vespa velutina allergy in the northern part of the country. Data of HVIT prescriptions reflect inter-regional variability with the predominance of Vespula (due to Vespula and Vespa) in the north and that of Polistes in the center and south of Spain.

Method for Nest Detection of the Yellow-Legged Hornet in High Density Areas.

The Asian hornet Vespa velutina is a social predator that has invaded several countries of Europe and Asia, impacting pollinators, apiculture and human health. One of the few effective control methods developed so far is the early destruction of nests. However, they are often built within dense vegetation, being difficult to detect. The aim of the method described here is to detect nests with a simple procedure, utilizing readily available materials, for widespread use in infested areas. The method has two phases, the first phase involves capturing and marking hornets, lured to a protein bait, and recording the flight directions of individuals to the nest and the time needed to complete a bait-nest-bait round trip, to estimate the distance. Collecting this information from two (or more) bait stations allows to delineate the approximate location of the nest. The second phase aims to determine the precise location of the nest, using sugary baits in the vicinity of the nest and conspicuous marks attached to the released hornets, to visually follow them up to their nest. This method is an alternative to other methods that are either ineffective in areas with high nest density or require expensive equipment and specialized training.

Assessment of an inexpensive trap design and survey method for vespine wasps (Hymenoptera, Vespidae, Vespinae)

The introduction of the predatory Giant Asian Hornet, Vespa mandarinia Smith, to North America in 2019 has motivated efforts to create early detection systems for this and other non-native social wasp species (Hymenoptera, Vespidae). Various trap and bait combinations have been used for this purpose, most of which require assembly and materials that are costly, reducing their usefulness in large-scale survey systems. This study tests an inexpensive and efficient trapping technique for detecting or surveying vespine wasps. Traps were made from reused plastic bottles containing a brown sugar and water bait. They were deployed at heights ranging from 0–6 m above ground in several configurations. Captures for traps suspended 1 m or greater above ground were, on average, nine times higher than the catch of ground-level traps. A rapid trap deployment method for large geographic areas was created, which captured seven different vespine wasp species along a 395 km east-west road transect from mountains to coastal plain in the Mid-Atlantic region of the United States. The trapping design and survey methodology described below is inexpensive and fast and could be used by land managers or citizen scientists to detect V. mandarinia, other exotic vespine, or conducted on a large-scale vespine diversity survey.

Les anaphylaxies aux piqûres de frelons asiatiques (Vespa velutina) : cas déclarés au Réseau d’Allergo-Vigilance® (RAV) de 2011 à 2021 et conduite à tenir

First identified in France in 2004 in the Bordeaux region, the Asian hornet Vespa velutina nigrithorax has since colonized all France; in the north, it has reached Belgium, the Netherlands, Germany and Great Britain, and in the south mainly Spain. This very fast expansion is explained by several factors, including a favorable climate, a great faculty of adaptation, and abundant food: the Asian hornet is unfortunately a great consumer of bees. Since 2011, 15 cases of Asian hornet anaphylaxis have been reported to the Allergo-Vigilance® network, mainly severe cases (Müller grade 3 and 4). The major allergen, Vesp v 5, is very similar to the corresponding Vespula allergen, Ves v 5, and venom immunotherapy with Vespula extracts seems effective.

Chemical and genetic evidences that multiple hornet colonies attack honeybee colonies

The yellow-legged hornet, Vespa velutina nigrithorax, is an invasive species that is causing numerous ecological and economic problems, particularly for beekeepers, whose apiaries are seriously affected by hornet predation. The effects may be intensified if hornet workers from different colonies are preying upon bees from the same apiary. Therefore, to determine whether such could occur, we sampled hornets found within identifiable colonies versus in front of beehives. We employed two complementary methodological approaches: the analysis of chemical markers (i.e., cuticular hydrocarbons) and genetic markers (i.e., microsatellites). Although there was chemical variation among hornets, we determined that at least two chemically homogeneous hornet groups could be found within each apiary studied (using K-means clustering). Furthermore, when hornet chemical dissimilarity was quantified at three different levels (within apiaries, within hornet colonies, and between hornet colonies), we discovered that the within-apiary dissimilarity was intermediate relative to within-colony and between-colony dissimilarity, suggesting that the hornets within a given apiary represented a mixture of individuals from more than one colony. Based on the genetic markers, hornet genetic diversity was low at the population level, as expected for this introduced species. That said, the genetic results mirrored the chemical results: genetic dissimilarity was larger between colonies and smaller within colonies. However, the hornets within a given apiary displayed an intermediate dissimilarity value. Consequently, both our chemical and genetic findings suggested that apiaries could be attacked by hornets from more than one colony.

Immune competence of the invasive hornet Vespa velutina and its native counterpart Vespa crabro: a comparison across caste and sex

Immune competence of the invasive hornet Vespa velutina and its native counterpart Vespa crabro: a comparison across caste and sex

Utility of DNA barcoding for identification of common Vespa species (Hymenoptera: Vespidae) from Yunnan, China

AbstractAs traditional Chinese medicine and edible insects, Vespa hornets have high economic value and huge market demand. Hornet breeding has become an important way to increase the income of mountain farmers in China, but the limitation of traditional identification methods has become the bottleneck of the modern development of hornet resources. In this study, a simple and reliable method for the molecular identification of typical hornets from Yunnan was successfully established. In the NCBI database, DNA sequences of hornet samples were aligned as Vespa analis, Vespa basalis, Vespa velutina, Vespa mandarinia, Vespa magnifica, Vespa binghami, Vespa soror by BLAST search. The efficiency of the PCR amplification of mitochondrial cytochrome C oxidase I (COI) gene sequences in all samples was 100% by using the optimized program. Moreover, a reference database for DNA barcodes of Vespa materials in Yunnan was constructed. This study provided a successful example for the identification of local insects of Yunnan and will be helpful to the development of wasp resources.

Xenosyangi sp. nov.: A new twisted-wing parasite species (Strepsiptera, Xenidae) from Gaoligong Mountains, Southwest China.

Here we report a new twisted-wing parasite species of the family Xenidae based on both morphological and molecular evidence. By using nearly complete mitogenomes, we confirmed the twisted-wing parasites on two wasps (Vespavelutina and Vespabicolor) (China: Yunnan) as the same species, and associated its neotenic females and alate males. Combining the mitogenomic data (COI) and morphological traits, this species was identified to be a new species of the genus Xenos, namely Xenosyangi Dong, Liu & Li, sp. nov. Detailed descriptions and illustrations are provided for the new species.