Exploring the efficacy of predacious diving beetles as potential nature-based solution for combatting the invasive mosquito Aedes albopictus (Skuse, 1894)

The invasive mosquito species Aedes albopictus (Skuse, 1894) is rapidly spreading in Europe, posing an increasing threat because of its high vector competence for chikungunya and dengue virus. An integrative and eco-friendly control of these populations is required to prevent mosquito-borne disease outbreaks. Traditionally-used insecticides or other chemical control agents are often expensive, harmful to the environment, strictly controlled or completely banned in several countries. Additionally, insecticide resistance is a potential threat. One possibility for biological control agents is the use of native aquatic beetles as natural predators of mosquitoes to boost Bacillus thuringiensis israelensis (Bti) interventions. Thirty predatory aquatic beetle taxa were caught in Belgium and kept at the Institute of Tropical Medicine’s insectary to test predation rate and prey choice on Aedes albopictus and Culex pipiens Linnaeus, 1758. Predation rates suggest at least four efficient dytiscid predators that are known to inhabit small, temporary habitats in Europe. Further experiments on prey choice reveal a clear preference for Aedes albopictus over alternative larval prey (Culex pipiens, Daphnia sp., Chaoboridae). We found a strong ecological overlap of the feeding niche of A. albopictus and the hunting zone of dytiscid predators in the benthic layer of small waterbodies. Our findings on the efficacy are very encouraging to further assess the potential of native predacious diving beetles as a biological control agent against the invasive A. albopictus in Europe

From a long‑distance threat to the invasion front : a review of the invasive Aedes mosquito species in Belgium between 2007 and 2020

Author contributions ID drafted the manuscript and revised it after comments of all co-authors. ID, TVL, KDW and AV carried out the mosquito identifications. ID, KDW, AS, AV, IV, JDW, JD, TVL and WVB collected data in the field and sorted the mosquitoes in the laboratory. WVB, ID and KDW managed the data. NS and JDW performed the DNA barcoding. WD and AV produced the morphological reference collection. WVB, ID, MM and RM coordinated the projects. MK performed the statistical analysis. All authors critically reviewed the manuscript. All authors read and approved the final manuscript.Data supporting the conclusions of this article are included within the article and its additional file. The datasets generated and analysed during the current study are available in the GBIF repository [44–50].ADDITIONAL FILE 1: TABLE S1. Overview of the trapping methods used to monitor invasive mosquito species (IMS) in Belgium during the different years (and projects) and in different risk scenarios, indicating the number of traps or larval sampling visits per site and the frequency of trapping or larval sampling. TABLE S2. Aedes albopictus detections in Belgium between 2007 and 2020 at the ten points of entry (PoEs) per year including the sampling perimeter, collection and detection methods, collection (light grey) and detection (dark grey) period, control measures (X), number of individuals (total, females, males, larvae and eggs) and project. TABLE S3. Aedes japonicus detections in Belgium between 2007 and 2020 at the four points of entry (PoEs) per year including the sampling perimeter, collection and detection methods, collection (light grey) and detection (dark grey) period, the control measures (X), number of individuals (total, females, males, larvae and eggs) and project. TABLE S4. Aedes koreicus detections in Belgium between 2007 and 2020 at the two points of entry (PoEs) per year including the sampling perimeter, collection and detection methods, collection (light grey) and detection (dark grey) period, control measures (X), number of individuals (total, females, males, larvae and eggs) and project.Invasive mosquito species (IMS) and their associated mosquito-borne diseases are emerging in Europe. In Belgium, the first detection of Aedes albopictus (Skuse 1894) occurred in 2000 and of Aedes japonicus japonicus (Theobald 1901) in 2002. Early detection and control of these IMS at points of entry (PoEs) are of paramount importance to slow down any possible establishment. This article reviews the introductions and establishments recorded of three IMS in Belgium based on published (2007–2014) and unpublished (2015–2020) data collected during several surveillance projects. In total, 52 PoEs were monitored at least once for the presence of IMS between 2007 and 2020. These included used tyre and lucky bamboo import companies, airports, ports, parking lots along highways, shelters for imported cutting plants, wholesale markets, industrial areas, recycling areas, cemeteries and an allotment garden at the country border with colonised areas. In general, monitoring was performed between April and November. Mosquitoes were captured with adult and oviposition traps as well as by larval sampling. Aedes albopictus was detected at ten PoEs, Ae. japonicus at three PoEs and Aedes koreicus (Edwards 1917) at two PoEs. The latter two species have established overwintering populations. The percentage of PoEs positive for Ae. albopictus increased significantly over years. Aedes albopictus is currently entering Belgium through lucky bamboo and used tyre trade and passive ground transport, while Ae. japonicus through used tyre trade and probably passive ground transport. In Belgium, the import through passive ground transport was first recorded in 2018 and its importance seems to be growing. Belgium is currently at the invasion front of Ae. albopictus and Ae. japonicus. The surveillance and control management actions at well-known PoEs associated to long-distance introductions are more straightforward than at less-defined PoEs associated with short-distance introductions from colonised areas. These latter PoEs represent a new challenge for IMS management in Belgium in the coming years. Aedes albopictus is expected to become established in Belgium in the coming years, hence increasing the likelihood of local arbovirus transmission. The implementation of a sustainable, structured and long-term IMS management programme, integrating active and passive entomological surveillance, vector control and Public Health surveillance is therefore pivotal.The MODIRISK project (2007–2010) was funded by the Belgian Science Policy Programs; the EXOSURV project (2012) by the Federal, Flemish, Walloon and Brussels Capital region governments, the FASFC project (2013–2016) by the Federal Agency for the Safety of the Food Chain (FASFC), the MEMO and MEMO+2020 projects (2017–2020) by the Flemish, Walloon and Brussels regional governments and the Federal Public Service (FPS) Public Health, Food Chain Safety and Environment in the context of the National Environment and Health Action Plan (NEHAP) (Belgium), and the DiMoc project by the 2018–2019 BiodivERsA3 ERA-Net COFUND programme with the funding organisation FWO. The Barcoding Facility for Organisms and Tissues of Policy Concern is financed by the Belgian Science Policy Office (Belspo) as Belgian federal in-kind contribution to the European Research Infrastructure Consortium “LifeWatch”. The Outbreak Research Team of the Institute of Tropical Medicine is financially supported by the Department of Economy, Science and Innovation of the Flemish government.https://parasitesandvectors.biomedcentral.comam2023Veterinary Tropical Disease

Exploring the efficacy of predacious diving beetles as potential nature-based solution for combatting the invasive mosquito Aedes albopictus (Skuse, 1894)

Abstract: The invasive mosquito species Aedes albopictus (Skuse, 1894) is rapidly spreading in Europe, posing an increasing threat because of its high vector competence for chikungunya and dengue virus. An integrative and eco-friendly control of these populations is required to prevent mosquito-borne disease outbreaks. Traditionally-used insecticides or other chemical control agents are often expensive, harmful to the environment, strictly controlled or completely banned in several countries. Additionally, insecticide resistance is a potential threat. One possibility for biological control agents is the use of native aquatic beetles as natural predators of mosquitoes to boost Bacillus thuringiensis israelensis (Bti) interventions. Thirty predatory aquatic beetle taxa were caught in Belgium and kept at the Institute of Tropical Medicine's insectary to test predation rate and prey choice on Aedes albopictus and Culex pipiens Linnaeus, 1758. Predation rates suggest at least four efficient dytiscid predators that are known to inhabit small, temporary habitats in Europe. Further experiments on prey choice reveal a clear preference for Aedes albopictus over alternative larval prey (Culex pipiens, Daphnia sp., Chaoboridae). We found a strong ecological overlap of the feeding niche of A. albopictus and the hunting zone of dytiscid predators in the benthic layer of small waterbodies. Our findings on the efficacy are very encouraging to further assess the potential of native predacious diving beetles as a biological control agent against the invasive A. albopictus in Europe

First detections of Culiseta longiareolata (Diptera: Culicidae) in Belgium and the Netherlands

Culiseta (Allotheobaldia) longiareolata (Macquart) (Diptera: Culicidae) is an ornithophilic mosquito species that occurs in the southern Palaearctic Region from the Azores to Central Asia, the Ethiopian Region, India, and Pakistan. Although it has a widespread distribution range, the species was only recently reported in Western and Central Europe. Between 2017 and 2020, larvae, pupae, and adults of Cs. longiareolata (n = 161) were found at 13 distinct locations in Belgium (n = 4) and The Netherlands (n = 9). Collected mosquitoes were morphologically identified and the identification was then validated by COI DNA barcoding. These are the first records of the species in the above-mentioned countries. The present results suggest that Cs. longiareolata could be increasing its distribution range in temperate regions, indicating a warming climate. As the species might be a potential vector of bird pathogens (e.g., West Nile virus), its spread in Western Europe is noteworthy

FIGURE 1 in First record of the West Nile virus bridge vector Culex modestus Ficalbi (Diptera Culicidae) in Belgium, validated by DNA barcoding

FIGURE 1. (A) Posterior part of the mounted Cx. modestus larva. Zoom on the diagnostic characteristic of the siphon, showing disarrayed insertion points of the ventral siphonal setae. (B) Posterior part of a mounted Cx. pipiens larva.Published as part of Wolf, Katrien De, Vanderheyden, Ann, Deblauwe, Isra, Smitz, Nathalie, Gombeer, Sophie, Vanslembrouck, Adwine, Meganck, Kenny, Dekoninck, Wouter, Meyer, Marc De, Backeljau, Thierry, Müller, Ruth & Bortel, Wim Van, 2021, First record of the West Nile virus bridge vector Culex modestus Ficalbi (Diptera Culicidae) in Belgium, validated by DNA barcoding, pp. 131-139 in Zootaxa 4920 (1) on page 134, DOI: 10.11646/zootaxa.4920.1.7, http://zenodo.org/record/447179

First record of the West Nile virus bridge vector Culex modestus Ficalbi (Diptera: Culicidae) in Belgium, validated by DNA barcoding

Wolf, Katrien De, Vanderheyden, Ann, Deblauwe, Isra, Smitz, Nathalie, Gombeer, Sophie, Vanslembrouck, Adwine, Meganck, Kenny, Dekoninck, Wouter, Meyer, Marc De, Backeljau, Thierry, Müller, Ruth, Bortel, Wim Van (2021): First record of the West Nile virus bridge vector Culex modestus Ficalbi (Diptera Culicidae) in Belgium, validated by DNA barcoding. Zootaxa 4920 (1): 131-139, DOI: https://doi.org/10.11646/zootaxa.4920.1.

DNA identification and diversity of the vector mosquitoes Culex pipiens s.s. and Culex torrentium in Belgium (Diptera: Culicidae)

This survey reports on the DNA identification and occurrence of Culex torrentium and Cx. pipiens s.s. in Belgium. These native disease-vector mosquito species are morphologically difficult to separate, and the biotypes of Cx. pipiens s.s. are morphologically indistinguishable. Culex torrentium and Cx. pipiens s.s. were identified using the COI and ACE2 loci. We recorded 1248 Cx. pipiens s.s. and 401 Cx. torrentium specimens from 24 locations in Belgium (collected between 2017 and 2019). Culex pipiens biotypes pipiens and molestus, and their hybrids, were differentiated using fragment-size analysis of the CQ11 locus (956 pipiens and 227 molestus biotype specimens, 29 hybrids). Hybrids were observed at 13 out of 16 sympatric sites. These results confirm that both species are widespread in Belgium, but while Cx. torrentium revealed many COI haplotypes, Cx. pipiens s.s. showed only one abundant haplotype. This latter observation may either reflect a recent population-wide demographic or range expansion, or a recent bottleneck, possibly linked to a Wolbachia infection. Finally, new evidence is provided for the asymmetric but limited introgression of the molestus biotype into the pipiens biotype