Human-biting behavior of Leptoconops irritans (Diptera: Ceratopogonidae) in a touristic area of the Balearic Islands (Spain)

Human-biting behavior of Leptoconops irritans (Diptera: Ceratopogonidae) in a touristic area of the Balearic Islands (Spain) | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Human-biting behavior of Leptoconops irritans (Diptera: Ceratopogonidae) in a touristic area of the Balearic Islands (Spain) Mikel Alexander González, Carlos Barceló, Aroa Rodríguez-López, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5453929/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 30 Jan, 2025 Read the published version in Parasitology Research → Version 1 posted 9 You are reading this latest preprint version Abstract Biting gnats of genus Leptoconops Skuse 1889 are small blood-feeding insects recognized as highly irritating diurnal pests in certain regions around the globe. In Europe, their presence is poorly documented, except in France and Italy. Following reports of human discomfort in a touristic area of Menorca, Balearic Islands (Spain), a small-scale study was conducted to identify the biting species and assess their preferred biting sites using a human-landing assay along a habitat gradient in a coastal dune area. Leptoconops irritans (Noé, 1905) was identified based on morphological features and DNA barcoding. This species reached high densities (average rates of 3.3 landings/min), particularly near coastal dune vegetation. No statistically significant differences were found among the four main body site landings of L. irritans (F 3,6.023 = 1.80, p = 0.250): head (n = 91, 53.8%), lower extremities (n = 39, 23.1%), upper extremities (n = 37, 21.8%) and other covered areas (n = 2, 0.2%). Landing preferences varied among the three volunteers and bites progressed differently. This study represents the second documented case of Leptoconops gnats causing human discomfort in Spain. We hope this research stimulates further interest in this understudied genus, which has been largely overlooked across much of Europe. Biting gnats coastal dune diurnal pest landing preferences Mediterranean islands Menorca Figures Figure 1 Figure 2 1. Introduction Leptoconops Skuse 1889, is a genus of tiny, blood-sucking gnats belonging to the family Ceratopogonidae. These gnats are notorious for their painful bites, which can cause significant irritation and allergic reactions in humans and animals (Kettle 1962). Leptoconops gnats are considered as much troublesome as other members of the same family (i.e. Culicoides ) in terms of direct nuisance to humans, such as Culicoides impunctatus Goetghebuer 1920 in Europe or Culicoides furens (Poey 1853) in the Americas (Carter 192; Linley and Davies 1971; Blackwell et al. 1994). However, Culicoides biting midges are better known due to their role as vectors of several pathogens of medical-veterinary importance (Kettle 1977). Knowledge about Leptoconops in Europe is limited. Most research in this genus focused on its biology and ecology in Italy and France, mainly published between the 60’s and the 80’s (Fausto et al. 2007). In Spain, only a few local studies have confirmed the presence of Leptoconops in specific regions such as Catalonia, Andalusia, Aragón, and the Basque Country (Ortiz and Ordeix 2009; Delecolle 1999; González et al. 2013; Obregon et al. 2019), but its distribution and potential public health impact remains largely understudied. For this reason, it is reasonable to hypothesize that this genus is more widely distributed. This lack of awareness may lead to their presence going unnoticed or their nuisance being misidentified with other groups, such as Simuliidae (black flies), which are also small, dark-colored flies that produce painful bites. Enhanced awareness and targeted research are essential to fully understand the distribution and impact of Leptoconops in Spain. This study was initiated after a personal communication by Dr. Albert Bertolero about small insects that were biting him aggressively while conducting sampling on turtles in the dunes of Cala Tirant (Menorca, Spain). We aimed to confirm the identity of the human-biting species and gather additional information on its biting preferences. 2. Material and methods A small-scale study was conducted on June 7, 2023, at Cala Tirant (40°02'39.7"N, 4°06'10.1"E), in the municipality of Es Mercadal, on the north coast of the island of Menorca (Balearic Islands, Spain) (Fig. 1 A). Cala Tirant is a 600-meter cove located in a large bay, characterized by fine golden sand and a dune system with a continuous gradient of vegetation from the first dunes to the second dunes (foredunes). A nearby marsh drains into the area, forming a marsh at the back of the cove. The surrounding landscape feature low hills with bushes and tamarisk trees. There are also a few apartments, bars, and houses situated on both sides of the cove. The climate of the area under the Emberger classification is arid-semi humid. During the summer months, the average temperature typically ranges from 25 to 30 degrees and precipitation is quite low, usually ranging from 5 to 15 millimetres per month (Pons et al. 2017). Three locations were selected for a human-landing assay, set along a gradient from the seashore to the back of the cove (0–300 m) (Fig. 1 B). The first location (position 1) was 5 meters from the seashore, the second (position 2) was at the edge of the dune area, and the third (position 3) was behind the torrent in the Tamarix sp. vegetation zone, with approximately 100 meters between each point (Fig. 1 B). Three researchers (MAG, CB, and MAM) volunteered as human bait to assess the landings of Leptoconops midges. In random order, one of the volunteers stood upright with their legs (from knee to feet) and arms (from shoulders) exposed for 3 minutes, while one of the other researchers collected insects landing using a mouth-operated entomological aspirator. The remaining volunteers recorded the human landing activity. Specimens that remained perched for at least 3 seconds were aspirated and counted as valid. Afterward, the other three volunteers took turns being exposed at the same location. This process was repeated at the second and third sampling points. For each detected landing, number of insects and general position on the body where the biting gnats perched was noted for the uncovered areas of the body (head-neck, upper extremities and lower extremities). Landings on covered areas, such as the back, were discarded. Once the first round in the three positions was completed, the same round was repeated once, alternating the order of the volunteers. The participants were all men with ages comprised between 38 and 53 years. The day of the trial any of the participants used cologne or any product that might modify human skin odour. The first round was conducted at 7:15 a.m. (Tª 17–18°C), and the second at 8:15 a.m. (Tª 18–20°C) on a sunny day with light wind. Additionally, the vegetation of the area was sampled for 10 minutes using a sweep net (at ground level and striking the vegetation) to determine whether the gnats were resting in those areas. Specimens were stored in 70% ethanol and transported to the laboratory for species identification. A subsample of Leptoconops (n = 5) was mounted on slides and identified using previously published keys (Carter 1921). The remaining collected specimens were identified as the same species. A 658 bp fragment of the cytochrome Oxidase Subunit I (COI) gene was amplified and sequenced in three specimens following the procedures described in Gonzalez (González et al. 2024a, b) with a modification in the amplification reaction. It started with a polymerase activation phase at 94ºC for 4 minutes followed by 35 cycles at 94ºC for 1 min, 50º C for 1 min (in the previous works was set at 40º C), and 72ºC for 1 min, followed by a final extension for 10 min at 72ºC. Voucher specimens were stored in the department of Zoology of the University of the Balearic Islands. Landing rates were calculated as the number of landings divided by the time exposed for the three operators (pooled). Generalized Linear Model (GLM) with normal distributed errors was used to analyse differences in the landings of Leptoconops spp. The number of captures were log10 transformed. Volunteer and the interaction between volunteer identity and the site of landing were included as random factors while the study area and site of landing were included as fixed factors. The statistically significant interaction between volunteer identity and site of landing was interpreted with slice tests. All the analyses were done in JMP 9.0 (SAS Institute). 3. Results and discussion All the specimens collected on human-volunteers corresponded with Leptoconops irritans (Noé, 1905) females (n = 169). No specimens were collected by sweeping the vegetation. Leptoconops irritans can be easily separated from the remaining Leptoconops species by the characteristic whitish-isabella colored abdomen, the elongated proboscis (exceeding the head length) and the unique long and slender palpus, among others (Fig. 2 A and 2 B). In Spain, this species has only been recorded in the region of Catalonia (Ortiz and Ordeix 2009), thus this record represents the second report in the country. High-quality sequences of COI were obtained from two out of the three sequenced specimens (GenBank accession numbers: requested, under revision) and showed 98.04%-98.53% of homology with the L. irritans sequences from Italy (OM672386-90-91-92-93). Both sequences differed in three nucleotides. No statistical differences were found between body sites of landing (F 3,6.023 = 1.80, p = 0.250), but L. irritans showed different preference for body sites within the volunteers (F 3,63.74; p < 0.001). Overall, most of the landings (53.8%) occurred on the head-neck, followed by lower extremities, upper extremities, and few landings in other body sites (Fig. 2 C). Specifically, the three sites of the body with more landings were the head (n = 74), the calves (n = 21), and the back neck (n = 10). However, such preferences depended on the volunteer. For example, the head was the preferred site selected in two volunteers (0.77 ± 0.10 and 0.68 ± 0.09) but the legs were the preferred site in the third volunteer (0.50 ± 0.10). In absence of current studies on trophic preferences, previous research has suggested that Leptoconops species have an affinity to feed on head and arms of humans, causing nuisance by crawling in the hair, beneath clothes, and in the ears (Carter 1921), which aligns with our field observations. In fact, we observed Leptoconops having a high tendency to fly around the head; they were hovering around and quickly passed through the hair to reach the scalp, remaining well-fixed on the skin (the mouth aspirator was unable to remove them once they were fixed). Leptoconops irritans bites are noticeable and painful, resembling those of black flies, with a small puncture wound (red dot) at the center of the papule, which is typical of telmophagus-feeding insects (Fig. 2 D and 2 E). Bites of Leptoconops can cause varied skin reactions, ranging from mild, itchy, pink-red lesions that resolve quickly, to severe symptoms with intense itching, notable edema, and polymorphic conditions that can progress to impetiginized or bullous lesions with serous or sero-hemorrhagic content (ADOI 2024) Among the three volunteers, only one developed small skin lesions that persisted and remained itchy for 15 days (Fig. 2 E). This Leptoconops species is well-known in Italy, where is thought to be widely distributed, particularly in the coastal plains. Locally called “serafiche” or “serafica”, these tiny gnats are extremely bothersome when they occur in large numbers during their peak activity period, gaining a notorious evil reputation and limiting the use of certain areas as tourist attractions and recreational locations (Carter 1921; Bettini 1968; Polidori et al. 2023). Despite the notorious flight activity of L. irritans observed at the coast dunes during the study, it is unlikely to be a significant problem as their populations dismiss throughout the summer (Carter 1921). Their peak activity occurs early in the morning, around 8.00 a.m. (Carrieri et al. 2011), rather than at midday when tourists are more likely sunbathing. Significant differences were found along the habitat gradient (F 2,58.2 = 8.55; p = 0.0006). A lower number of L. irritans were collected at the seashore (position 1) compared to dune habitats (p < 0.001) and no differences were found between position 2 and position 3 (t 58.16 = 0.29, p = 0.77). A higher number of landings were recorded in position 3: 4.7 landings/min, followed by position 2: 4.1 landings/min and position 1: 0.9 landing/min. In the absence of more detailed information and based on previous descriptions of its habitat, it is plausible that their immature stage development is linked to the permanent marsh at the back of the beach. In Europe, this species is frequent in coastal environments, along with Leptoconops kerteszi Kieffer, 1908. The latter breeds in coastal habitat on sandy shores devoid of vegetation and remains constantly damp due to capillarity rise of saltwater (Majori et al. 1970; Raspi et al. 2007), while L. irritans can be also found both near the sea or in soils further inland, specifically in calcareous, halomorphic soils that cracks polygonally upon drying (Rioux et al. 1968; Bettini 1968; Carrieri et al. 2011). In conclusion, our study has confirmed the presence of L. irritans in Spain and provides new COI sequence data that enhances our understanding of this species. By documenting its biting behaviour and preferences, particularly the tendency to land on the head and extremities, we contribute valuable insights into its body preferences for humans. This research underscores the importance of continued local investigations to better understand and manage L. irritans and its impact on human activities. By expanding knowledge of this understudied genus within Spain, we aim to encourage further research in other regions where its presence has been noted but remains unexplored. Declarations Acknowledgement s Special thanks to Dr. Albert Bertolero for alerting us to the insect bites in the area and Dr. Daniel Bravo-Barriga for his assistance with the COI sequences. Author contributions Mikel A González: Investigation, methodology, data curation, and writing – original draft, review and editing; Carlos Barceló: Investigation, methodology, review and editing; Aroa Rodriguez: data curation, visualization. Jordi Figuerola: formal analysis and writing – review and editing; Miguel Angel Miranda: Investigation, methodology, data curation, supervision, funding acquisition; writing – review and editing. Funding statement This work was funded by BIOME - Ajuts del Consell Insular de Menorca per a estudis i investigacions ambientals a la Reserva de la Biosfera de Menorca 2023. The post-doc position of Mikel A. González is funded by Fundación “La Caixa” through the project ARBOPREVENT (HR22-00123). Data availability statement Data is available upon request. Conflicts of interest The authors have no relevant financial or non-financial interests to disclose. Consent to participate Not applicable. Consent for publication Not applicable. Competing interests The authors declare no competing interests. Ethical statements Considering that Leptoconops spp.do not transmit pathogens, the University of the Balearic Islands ethics committee deemed formal approval unnecessary. Nonetheless, the authors involved in the field experiment provide their signed consent (attached). References ADOI (Associazione Dermatologi-Venereologi Ospedalieri Italiani e della Sanità Pubblica) (2024) Patologia cutanea da puntura insetti. https://www.adoi.it/patologia-cutanea-da-puntura-insetti/. Accessed 17 Jun 2024 Bettini EF (1968) Leptoconops irritans Noé in Grossetano: problems in control. Rev di Parassitol 29 (1):33–47 Blackwell A, Mordue (Luntz) AJ and Mordue W (1994) Identification of bloodmeals of the Scottish biting midge, Culicoides impunctatus , by indirect enzyme-linked-immunosorbent-assay (Elisa). Med Vet Ent 8: 20-24. https://doi.org/10.1111/j.1365-2915.1994.tb00378.x Carrieri M, Montemurro E, Valentino SV et al (2011) Influence of environmental and meteorological factors on the biting activity of Leptoconops noei and Leptoconops irritans (Diptera: Ceratopogonidae) in Italy. J Am Mosq Control Assoc 27:30–38. https://doi.org/10.2987/8756-971X-27.1.30 Carter HF (1921) A Revision of the Genus Leptoconops , Skuse. Bull Entomol Res 12:1–28. https://doi.org/10.1017/S0007485300044813 Delecolle J (1999) Ceratopogonidés (Diptera, Nematocera) do Los Monegros. Bol la Soc Entomol Aragon 24:137 Fausto AM, Belardinelli MC, Cocchi M et al (2007) Le serafiche ( Leptoconops spp., Diptera: Ceratopogonidae) nelle aree umide del litorale grossetano: aspetti biologici e socio-sanitari. Atti Acc Naz It Entomol 55: 79–83 Majori, S Bettini, E Finizio GP (1970) Research on Ceratopogonidae in the province of Grosseto. IV. Identification of the breeding places of Leptoconops ( Holoconops ) kerteszi Kieffer, 1908. Riv Parassitol 31:279–84 González MA, López S, Goldarazena A (2013) New record of the biting midge Leptoconops noei in Northern Spain: notes on its seasonal abundance and flying height preference. J Insect Sci 13:1–10. https://doi.org/10.1673/031.013.4501 González MA, Magallanes S, Bravo-Barriga D et al (2024a) Sampling of Culicoides with nontraditional methods provides unusual species composition and new records for southern Spain. Parasites and Vectors 17:1–14. https://doi.org/10.1186/s13071-024-06414-2 González MA, Ruiz-Arrondo I, Magallanes S et al (2024b) Molecular and morphological analysis revealed a new Lipoptena species (Diptera: Hippoboscidae) in southern Spain harbouring Coxiella burnetii and bacterial endosymbionts. Vet Parasitol 332: 110300. https://doi.org/10.1016/j.vetpar.2024.110300 Kettle DS (1977). Biology and bionomics of bloodsucking ceratopogonids. Annu Rev Entomol 22(1): 33-51. Kettle DS (1962) The bionomics and control of Culicoides and Leptoconops (Diptera, Ceratopogonidae = Heleidae). Annu Rev Entomol 7 (1):401–408 Linley JR and Davies JB (1971) Sandflies and tourism in Florida and the Bahamas and Caribbean Area. J Econ Entomol 64: 264-278. https://doi.org/10.1093/jee/64.1.264 Obregon R, Flores E, Jordano D (2019) First report of the Asian tiger mosquito, Aedes ( Stegomyia ) albopictus Skuse, 1984 (Diptera, Culicidae) in Cordoba (southern Spain). new challenges for the administration and citizens of Cordoba. J Eur Mosq Control Assoc 37:29–33 Ortiz J, Ordeix M (2009) Espiadimonis, nàiades, sabaters i cuques de capsa. Els macroinvertebrats dels rius i zones humides de Catalunya. Centre d’Estudis dels Rius Mediterranis – Museu del Ter – Eumo editorial, Vic. Polidori C, Gabrieli P, Arnoldi I, et al (2023) Morphological and molecular insights into the diversity of Leptoconops biting midges from a heavily infested Mediterranean area. Curr Res Parasitol Vector-Borne Dis 4:100142. https://doi.org/10.1016/j.crpvbd.2023.100142 Pons GX, Martín-Prieto J, Mir-Gual M et al (2017) Los sistemas dunares costeros de Menorca. Monogr la Soc d’Historia Nat les Balear 25: 87–110 Raspi A, Canovai R, Loni A, Santini L (2007) Leptoconops ( Holoconops ) kerteszi Kieffer (Diptera: Ceratopogonidae) in the coastal area of Grosseto: Eeo-ethological aspects. Bull Insectology 60:1–6 Rioux JA, Descous S, Corre JJ et al (1968). Ecologie de Leptoconops irritans Noé, 1905 en moyenne Camargue. Localisation et dynamique des biotopes larvaires. Rev Écol (La Terre et La Vie) 22(4): 458-469. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 30 Jan, 2025 Read the published version in Parasitology Research → Version 1 posted Editorial decision: Revision requested 03 Dec, 2024 Reviews received at journal 02 Dec, 2024 Reviews received at journal 30 Nov, 2024 Reviewers agreed at journal 17 Nov, 2024 Reviewers agreed at journal 15 Nov, 2024 Reviewers invited by journal 15 Nov, 2024 Editor assigned by journal 15 Nov, 2024 Submission checks completed at journal 14 Nov, 2024 First submitted to journal 14 Nov, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5453929","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Short Report","associatedPublications":[],"authors":[{"id":385944557,"identity":"4774a1d8-3e29-4beb-b5b3-8c707da104e8","order_by":0,"name":"Mikel Alexander González","email":"","orcid":"","institution":"Doñana Biological Station – Spanish Research Council (EBD-CSIC)","correspondingAuthor":false,"prefix":"","firstName":"Mikel","middleName":"Alexander","lastName":"González","suffix":""},{"id":385944558,"identity":"992567af-65c6-41d4-8ac1-c7a3c5e63347","order_by":1,"name":"Carlos Barceló","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5klEQVRIie2PsQrCMBCGrwhxiXQ9qPoMka7isyQIdevi4lgQ4qazdOgr+AgtXaOugku7dK6bQgdTQXSKujnkG4674eP/D8Bi+U+cVA/+WAsYA8EvnJfCIfhdyQE+Ke5qX6R1A6Eb52XBF0ex9iKnvBoUVDOWbSXM8RD4jKuzkP2041ODwnT7vBeBiBQlKKRWkBPPVIy5FeS0AZEo2r0KeWiV7s1UjKFOoQTETrVTpo8UMBXDUwX6F5yPFPGRq6kv+9nSMynuJnCKuhmHQ9Up63oxGSTxMruYij3D3g8n+ixYLBaLxcgdiRVNkOEh9aUAAAAASUVORK5CYII=","orcid":"","institution":"University of the Balearic Islands","correspondingAuthor":true,"prefix":"","firstName":"Carlos","middleName":"","lastName":"Barceló","suffix":""},{"id":385944559,"identity":"06a91274-e70b-41ad-8ec3-8181988b2817","order_by":2,"name":"Aroa Rodríguez-López","email":"","orcid":"","institution":"University of the Balearic Islands","correspondingAuthor":false,"prefix":"","firstName":"Aroa","middleName":"","lastName":"Rodríguez-López","suffix":""},{"id":385944560,"identity":"1c97f7e2-3a5b-4058-9245-e5bb608a7b34","order_by":3,"name":"Jordi Figuerola","email":"","orcid":"","institution":"Doñana Biological Station – Spanish Research Council (EBD-CSIC)","correspondingAuthor":false,"prefix":"","firstName":"Jordi","middleName":"","lastName":"Figuerola","suffix":""},{"id":385944561,"identity":"13116ebb-8dd6-4915-aeaf-64477fbb1ed4","order_by":4,"name":"Miguel Ángel Miranda","email":"","orcid":"","institution":"University of the Balearic Islands","correspondingAuthor":false,"prefix":"","firstName":"Miguel","middleName":"Ángel","lastName":"Miranda","suffix":""}],"badges":[],"createdAt":"2024-11-14 12:38:19","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5453929/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5453929/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00436-024-08447-z","type":"published","date":"2025-01-30T15:57:40+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":71743077,"identity":"d39c7043-5365-4cca-917d-5b90879df66b","added_by":"auto","created_at":"2024-12-18 08:24:56","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":3675203,"visible":true,"origin":"","legend":"\u003cp\u003eLocation and setup of the human-landing assay at Cala Tirant, Menorca, Spain. (\u003cstrong\u003eA\u003c/strong\u003e) Map showing the location of Cala Tirant on the north coast of Menorca (Balearic Islands, Spain) within the Mediterranean Sea, highlighted by the red box. (\u003cstrong\u003eB\u003c/strong\u003e) The three sampling points selected for the human-landing assay: the first point (1\u003csup\u003est\u003c/sup\u003e position) was located 5 meters from the seashore, the second point (2\u003csup\u003end\u003c/sup\u003e position) near the beginning of the dune area, and the third point (3\u003csup\u003erd\u003c/sup\u003e position) behind the marsh\u003c/p\u003e","description":"","filename":"Fig.1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5453929/v1/b28529b6f75f5ca65adb758a.jpg"},{"id":71743034,"identity":"5d37fe70-b9c8-4db7-8e97-a6e82ecff059","added_by":"auto","created_at":"2024-12-18 08:24:51","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":1704140,"visible":true,"origin":"","legend":"\u003cp\u003eMorphology, landing preferences, and bite reactions of \u003cem\u003eLeptoconops\u003c/em\u003e \u003cem\u003eirritans \u003c/em\u003emidges. \u003cstrong\u003e(A and B)\u003c/strong\u003e Close-up of in dorsal view (bottom) and lateral view (top). \u003cstrong\u003e(C)\u003c/strong\u003e Diagram showing the preferred landing sites on the human body, with highlighted regions indicating areas of highest landing frequency. The number of landings is expressed for each body part. \u003cstrong\u003e(D and E)\u003c/strong\u003e \u003cem\u003eBites on the body of one of the volunteers. \u003c/em\u003eAppearance a few minutes after biting (top image) and several days after (bottom images)\u003c/p\u003e","description":"","filename":"Fig.2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-5453929/v1/5edcc48027665d6615e9f5bb.jpg"},{"id":75351448,"identity":"d8cbbd7b-4cb8-43bb-b1df-d12eec8dfc02","added_by":"auto","created_at":"2025-02-03 16:11:28","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":5837988,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5453929/v1/fa69366c-e0c8-4298-acd7-7a04eefaa859.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Human-biting behavior of Leptoconops irritans (Diptera: Ceratopogonidae) in a touristic area of the Balearic Islands (Spain)","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003e \u003cem\u003eLeptoconops\u003c/em\u003e Skuse 1889, is a genus of tiny, blood-sucking gnats belonging to the family Ceratopogonidae. These gnats are notorious for their painful bites, which can cause significant irritation and allergic reactions in humans and animals (Kettle 1962). \u003cem\u003eLeptoconops\u003c/em\u003e gnats are considered as much troublesome as other members of the same family (i.e. \u003cem\u003eCulicoides\u003c/em\u003e) in terms of direct nuisance to humans, such as \u003cem\u003eCulicoides impunctatus\u003c/em\u003e Goetghebuer 1920 in Europe or \u003cem\u003eCulicoides furens\u003c/em\u003e (Poey 1853) in the Americas (Carter 192; Linley and Davies 1971; Blackwell et al. 1994). However, \u003cem\u003eCulicoides\u003c/em\u003e biting midges are better known due to their role as vectors of several pathogens of medical-veterinary importance (Kettle 1977). Knowledge about \u003cem\u003eLeptoconops\u003c/em\u003e in Europe is limited. Most research in this genus focused on its biology and ecology in Italy and France, mainly published between the 60\u0026rsquo;s and the 80\u0026rsquo;s (Fausto et al. 2007).\u003c/p\u003e \u003cp\u003eIn Spain, only a few local studies have confirmed the presence of \u003cem\u003eLeptoconops\u003c/em\u003e in specific regions such as Catalonia, Andalusia, Arag\u0026oacute;n, and the Basque Country (Ortiz and Ordeix 2009; Delecolle 1999; Gonz\u0026aacute;lez et al. 2013; Obregon et al. 2019), but its distribution and potential public health impact remains largely understudied. For this reason, it is reasonable to hypothesize that this genus is more widely distributed. This lack of awareness may lead to their presence going unnoticed or their nuisance being misidentified with other groups, such as Simuliidae (black flies), which are also small, dark-colored flies that produce painful bites. Enhanced awareness and targeted research are essential to fully understand the distribution and impact of \u003cem\u003eLeptoconops\u003c/em\u003e in Spain.\u003c/p\u003e \u003cp\u003eThis study was initiated after a personal communication by Dr. Albert Bertolero about small insects that were biting him aggressively while conducting sampling on turtles in the dunes of Cala Tirant (Menorca, Spain). We aimed to confirm the identity of the human-biting species and gather additional information on its biting preferences.\u003c/p\u003e"},{"header":"2. Material and methods","content":"\u003cp\u003eA small-scale study was conducted on June 7, 2023, at Cala Tirant (40\u0026deg;02'39.7\"N, 4\u0026deg;06'10.1\"E), in the municipality of Es Mercadal, on the north coast of the island of Menorca (Balearic Islands, Spain) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eA). Cala Tirant is a 600-meter cove located in a large bay, characterized by fine golden sand and a dune system with a continuous gradient of vegetation from the first dunes to the second dunes (foredunes). A nearby marsh drains into the area, forming a marsh at the back of the cove. The surrounding landscape feature low hills with bushes and tamarisk trees. There are also a few apartments, bars, and houses situated on both sides of the cove. The climate of the area under the Emberger classification is arid-semi humid. During the summer months, the average temperature typically ranges from 25 to 30 degrees and precipitation is quite low, usually ranging from 5 to 15 millimetres per month (Pons et al. 2017).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThree locations were selected for a human-landing assay, set along a gradient from the seashore to the back of the cove (0\u0026ndash;300 m) (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB). The first location (position 1) was 5 meters from the seashore, the second (position 2) was at the edge of the dune area, and the third (position 3) was behind the torrent in the \u003cem\u003eTamarix\u003c/em\u003e sp. vegetation zone, with approximately 100 meters between each point (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eB). Three researchers (MAG, CB, and MAM) volunteered as human bait to assess the landings of \u003cem\u003eLeptoconops\u003c/em\u003e midges. In random order, one of the volunteers stood upright with their legs (from knee to feet) and arms (from shoulders) exposed for 3 minutes, while one of the other researchers collected insects landing using a mouth-operated entomological aspirator. The remaining volunteers recorded the human landing activity. Specimens that remained perched for at least 3 seconds were aspirated and counted as valid. Afterward, the other three volunteers took turns being exposed at the same location. This process was repeated at the second and third sampling points. For each detected landing, number of insects and general position on the body where the biting gnats perched was noted for the uncovered areas of the body (head-neck, upper extremities and lower extremities). Landings on covered areas, such as the back, were discarded. Once the first round in the three positions was completed, the same round was repeated once, alternating the order of the volunteers.\u003c/p\u003e \u003cp\u003eThe participants were all men with ages comprised between 38 and 53 years. The day of the trial any of the participants used cologne or any product that might modify human skin odour. The first round was conducted at 7:15 a.m. (T\u0026ordf; 17\u0026ndash;18\u0026deg;C), and the second at 8:15 a.m. (T\u0026ordf; 18\u0026ndash;20\u0026deg;C) on a sunny day with light wind. Additionally, the vegetation of the area was sampled for 10 minutes using a sweep net (at ground level and striking the vegetation) to determine whether the gnats were resting in those areas.\u003c/p\u003e \u003cp\u003eSpecimens were stored in 70% ethanol and transported to the laboratory for species identification. A subsample of \u003cem\u003eLeptoconops\u003c/em\u003e (n\u0026thinsp;=\u0026thinsp;5) was mounted on slides and identified using previously published keys (Carter 1921). The remaining collected specimens were identified as the same species. A 658 bp fragment of the cytochrome Oxidase Subunit I (COI) gene was amplified and sequenced in three specimens following the procedures described in Gonzalez (Gonz\u0026aacute;lez et al. 2024a, b) with a modification in the amplification reaction. It started with a polymerase activation phase at 94\u0026ordm;C for 4 minutes followed by 35 cycles at 94\u0026ordm;C for 1 min, 50\u0026ordm; C for 1 min (in the previous works was set at 40\u0026ordm; C), and 72\u0026ordm;C for 1 min, followed by a final extension for 10 min at 72\u0026ordm;C. Voucher specimens were stored in the department of Zoology of the University of the Balearic Islands.\u003c/p\u003e \u003cp\u003eLanding rates were calculated as the number of landings divided by the time exposed for the three operators (pooled). Generalized Linear Model (GLM) with normal distributed errors was used to analyse differences in the landings of \u003cem\u003eLeptoconops\u003c/em\u003e spp. The number of captures were log10 transformed. Volunteer and the interaction between volunteer identity and the site of landing were included as random factors while the study area and site of landing were included as fixed factors. The statistically significant interaction between volunteer identity and site of landing was interpreted with slice tests. All the analyses were done in JMP 9.0 (SAS Institute).\u003c/p\u003e"},{"header":"3. Results and discussion","content":"\u003cp\u003eAll the specimens collected on human-volunteers corresponded with \u003cem\u003eLeptoconops irritans\u003c/em\u003e (No\u0026eacute;, 1905) females (n\u0026thinsp;=\u0026thinsp;169). No specimens were collected by sweeping the vegetation. \u003cem\u003eLeptoconops irritans\u003c/em\u003e can be easily separated from the remaining \u003cem\u003eLeptoconops\u003c/em\u003e species by the characteristic whitish-isabella colored abdomen, the elongated proboscis (exceeding the head length) and the unique long and slender palpus, among others (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eA and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eB). In Spain, this species has only been recorded in the region of Catalonia (Ortiz and Ordeix 2009), thus this record represents the second report in the country. High-quality sequences of COI were obtained from two out of the three sequenced specimens (GenBank accession numbers: requested, under revision) and showed 98.04%-98.53% of homology with the \u003cem\u003eL. irritans\u003c/em\u003e sequences from Italy (OM672386-90-91-92-93). Both sequences differed in three nucleotides.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eNo statistical differences were found between body sites of landing (F\u003csub\u003e3,6.023\u003c/sub\u003e = 1.80, p\u0026thinsp;=\u0026thinsp;0.250), but \u003cem\u003eL. irritans\u003c/em\u003e showed different preference for body sites within the volunteers (F\u003csub\u003e3,63.74;\u003c/sub\u003e p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Overall, most of the landings (53.8%) occurred on the head-neck, followed by lower extremities, upper extremities, and few landings in other body sites (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eC). Specifically, the three sites of the body with more landings were the head (n\u0026thinsp;=\u0026thinsp;74), the calves (n\u0026thinsp;=\u0026thinsp;21), and the back neck (n\u0026thinsp;=\u0026thinsp;10). However, such preferences depended on the volunteer. For example, the head was the preferred site selected in two volunteers (0.77\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10 and 0.68\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09) but the legs were the preferred site in the third volunteer (0.50\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10). In absence of current studies on trophic preferences, previous research has suggested that \u003cem\u003eLeptoconops\u003c/em\u003e species have an affinity to feed on head and arms of humans, causing nuisance by crawling in the hair, beneath clothes, and in the ears (Carter 1921), which aligns with our field observations. In fact, we observed \u003cem\u003eLeptoconops\u003c/em\u003e having a high tendency to fly around the head; they were hovering around and quickly passed through the hair to reach the scalp, remaining well-fixed on the skin (the mouth aspirator was unable to remove them once they were fixed). \u003cem\u003eLeptoconops irritans\u003c/em\u003e bites are noticeable and painful, resembling those of black flies, with a small puncture wound (red dot) at the center of the papule, which is typical of telmophagus-feeding insects (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eD and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE). Bites of \u003cem\u003eLeptoconops\u003c/em\u003e can cause varied skin reactions, ranging from mild, itchy, pink-red lesions that resolve quickly, to severe symptoms with intense itching, notable edema, and polymorphic conditions that can progress to impetiginized or bullous lesions with serous or sero-hemorrhagic content (ADOI 2024) Among the three volunteers, only one developed small skin lesions that persisted and remained itchy for 15 days (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eE).\u003c/p\u003e \u003cp\u003eThis \u003cem\u003eLeptoconops\u003c/em\u003e species is well-known in Italy, where is thought to be widely distributed, particularly in the coastal plains. Locally called \u0026ldquo;serafiche\u0026rdquo; or \u0026ldquo;serafica\u0026rdquo;, these tiny gnats are extremely bothersome when they occur in large numbers during their peak activity period, gaining a notorious evil reputation and limiting the use of certain areas as tourist attractions and recreational locations (Carter 1921; Bettini 1968; Polidori et al. 2023). Despite the notorious flight activity of \u003cem\u003eL. irritans\u003c/em\u003e observed at the coast dunes during the study, it is unlikely to be a significant problem as their populations dismiss throughout the summer (Carter 1921). Their peak activity occurs early in the morning, around 8.00 a.m. (Carrieri et al. 2011), rather than at midday when tourists are more likely sunbathing.\u003c/p\u003e \u003cp\u003eSignificant differences were found along the habitat gradient (F\u003csub\u003e2,58.2\u003c/sub\u003e= 8.55; p\u0026thinsp;=\u0026thinsp;0.0006). A lower number of \u003cem\u003eL. irritans\u003c/em\u003e were collected at the seashore (position 1) compared to dune habitats (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) and no differences were found between position 2 and position 3 (t\u003csub\u003e58.16\u003c/sub\u003e = 0.29, p\u0026thinsp;=\u0026thinsp;0.77). A higher number of landings were recorded in position 3: 4.7 landings/min, followed by position 2: 4.1 landings/min and position 1: 0.9 landing/min. In the absence of more detailed information and based on previous descriptions of its habitat, it is plausible that their immature stage development is linked to the permanent marsh at the back of the beach. In Europe, this species is frequent in coastal environments, along with \u003cem\u003eLeptoconops kerteszi\u003c/em\u003e Kieffer, 1908. The latter breeds in coastal habitat on sandy shores devoid of vegetation and remains constantly damp due to capillarity rise of saltwater (Majori et al. 1970; Raspi et al. 2007), while \u003cem\u003eL. irritans\u003c/em\u003e can be also found both near the sea or in soils further inland, specifically in calcareous, halomorphic soils that cracks polygonally upon drying (Rioux et al. 1968; Bettini 1968; Carrieri et al. 2011).\u003c/p\u003e \u003cp\u003eIn conclusion, our study has confirmed the presence of \u003cem\u003eL. irritans\u003c/em\u003e in Spain and provides new COI sequence data that enhances our understanding of this species. By documenting its biting behaviour and preferences, particularly the tendency to land on the head and extremities, we contribute valuable insights into its body preferences for humans. This research underscores the importance of continued local investigations to better understand and manage \u003cem\u003eL. irritans\u003c/em\u003e and its impact on human activities. By expanding knowledge of this understudied genus within Spain, we aim to encourage further research in other regions where its presence has been noted but remains unexplored.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgement\u003c/strong\u003e\u003cstrong\u003es\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSpecial thanks to Dr. Albert Bertolero for alerting us to the insect bites in the area and Dr. Daniel Bravo-Barriga for his assistance with the COI sequences. \u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMikel A Gonz\u0026aacute;lez:\u003c/strong\u003e Investigation, methodology, data curation, and writing \u0026ndash; original draft, review and editing; \u003cstrong\u003eCarlos Barcel\u0026oacute;: \u003c/strong\u003eInvestigation, methodology, review and editing; \u003cstrong\u003eAroa Rodriguez: \u003c/strong\u003edata curation, visualization.\u003cstrong\u003e Jordi Figuerola:\u003c/strong\u003e formal analysis and writing \u0026ndash; review and editing;\u003cstrong\u003e Miguel Angel Miranda:\u003c/strong\u003e Investigation, methodology, data curation, supervision, funding acquisition; writing \u0026ndash; review and editing. \u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was funded by BIOME - Ajuts del Consell Insular de Menorca per a estudis i investigacions ambientals a la Reserva de la Biosfera de Menorca 2023. The post-doc position of Mikel A. Gonz\u0026aacute;lez is funded by Fundaci\u0026oacute;n \u0026ldquo;La Caixa\u0026rdquo; through the project ARBOPREVENT (HR22-00123).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData is available upon request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to participate\u003c/strong\u003e Not applicable. \u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e Not applicable. \u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e The authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical statements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsidering that \u003cem\u003eLeptoconops \u003c/em\u003espp.do not transmit pathogens, the University of the Balearic Islands ethics committee deemed formal approval unnecessary. Nonetheless, the authors involved in the field experiment provide their signed consent (attached).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eADOI (Associazione Dermatologi-Venereologi Ospedalieri Italiani e della Sanit\u0026agrave; Pubblica) (2024) Patologia cutanea da puntura insetti. https://www.adoi.it/patologia-cutanea-da-puntura-insetti/. Accessed 17 Jun 2024\u003c/li\u003e\n \u003cli\u003eBettini EF (1968) \u003cem\u003eLeptoconops irritans\u003c/em\u003e No\u0026eacute; in Grossetano: problems in control. Rev di Parassitol 29 (1):33\u0026ndash;47\u003c/li\u003e\n \u003cli\u003eBlackwell A, Mordue (Luntz) AJ and Mordue W (1994) Identification of bloodmeals of the Scottish biting midge, \u003cem\u003eCulicoides impunctatus\u003c/em\u003e, by indirect enzyme-linked-immunosorbent-assay (Elisa). Med Vet Ent 8: 20-24.\u0026nbsp;https://doi.org/10.1111/j.1365-2915.1994.tb00378.x\u0026nbsp;\u003c/li\u003e\n \u003cli\u003eCarrieri M, Montemurro E, Valentino SV et al (2011) Influence of environmental and meteorological factors on the biting activity of \u003cem\u003eLeptoconops noei\u003c/em\u003e and \u003cem\u003eLeptoconops irritans\u003c/em\u003e (Diptera: Ceratopogonidae) in Italy. J Am Mosq Control Assoc 27:30\u0026ndash;38. https://doi.org/10.2987/8756-971X-27.1.30\u003c/li\u003e\n \u003cli\u003eCarter HF (1921) A Revision of the Genus \u003cem\u003eLeptoconops\u003c/em\u003e, Skuse. Bull Entomol Res 12:1\u0026ndash;28. https://doi.org/10.1017/S0007485300044813\u003c/li\u003e\n \u003cli\u003eDelecolle J (1999) Ceratopogonid\u0026eacute;s (Diptera, Nematocera) do Los Monegros. Bol la Soc Entomol Aragon 24:137\u003c/li\u003e\n \u003cli\u003eFausto AM, Belardinelli MC, Cocchi M et al (2007) Le serafiche (\u003cem\u003eLeptoconops\u0026nbsp;\u003c/em\u003espp., Diptera: Ceratopogonidae) nelle aree umide del litorale grossetano: aspetti biologici e socio-sanitari. Atti Acc Naz It Entomol 55: 79\u0026ndash;83\u003c/li\u003e\n \u003cli\u003eMajori, S Bettini, E Finizio GP (1970) Research on Ceratopogonidae in the province of Grosseto. IV. Identification of the breeding places of \u003cem\u003eLeptoconops\u003c/em\u003e (\u003cem\u003eHoloconops\u003c/em\u003e) kerteszi Kieffer, 1908. Riv Parassitol 31:279\u0026ndash;84\u003c/li\u003e\n \u003cli\u003eGonz\u0026aacute;lez MA, L\u0026oacute;pez S, Goldarazena A (2013) New record of the biting midge \u003cem\u003eLeptoconops noei\u003c/em\u003e in Northern Spain: notes on its seasonal abundance and flying height preference. J Insect Sci 13:1\u0026ndash;10. https://doi.org/10.1673/031.013.4501\u003c/li\u003e\n \u003cli\u003eGonz\u0026aacute;lez MA, Magallanes S, Bravo-Barriga D et al (2024a) Sampling of Culicoides with nontraditional methods provides unusual species composition and new records for southern Spain. Parasites and Vectors 17:1\u0026ndash;14. https://doi.org/10.1186/s13071-024-06414-2\u003c/li\u003e\n \u003cli\u003eGonz\u0026aacute;lez MA, Ruiz-Arrondo I, Magallanes S et al (2024b) Molecular and morphological analysis revealed a new \u003cem\u003eLipoptena\u003c/em\u003e species (Diptera: Hippoboscidae) in southern Spain harbouring \u003cem\u003eCoxiella burnetii\u0026nbsp;\u003c/em\u003eand bacterial endosymbionts. Vet Parasitol 332: 110300. https://doi.org/10.1016/j.vetpar.2024.110300\u003c/li\u003e\n \u003cli\u003eKettle DS (1977). Biology and bionomics of bloodsucking ceratopogonids. 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Els macroinvertebrats dels rius i zones humides de Catalunya. Centre d\u0026rsquo;Estudis dels Rius Mediterranis \u0026ndash; Museu del Ter \u0026ndash; Eumo editorial, Vic.\u0026nbsp;\u003c/li\u003e\n \u003cli\u003ePolidori C, Gabrieli P, Arnoldi I, et al (2023) Morphological and molecular insights into the diversity of \u003cem\u003eLeptoconops\u003c/em\u003e biting midges from a heavily infested Mediterranean area. Curr Res Parasitol Vector-Borne Dis 4:100142. https://doi.org/10.1016/j.crpvbd.2023.100142\u003c/li\u003e\n \u003cli\u003ePons GX, Mart\u0026iacute;n-Prieto J, Mir-Gual M et al (2017) Los sistemas dunares costeros de Menorca. Monogr la Soc d\u0026rsquo;Historia Nat les Balear 25: 87\u0026ndash;110\u003c/li\u003e\n \u003cli\u003eRaspi A, Canovai R, Loni A, Santini L (2007) \u003cem\u003eLeptoconops\u003c/em\u003e (\u003cem\u003eHoloconops\u003c/em\u003e) \u003cem\u003ekerteszi\u0026nbsp;\u003c/em\u003eKieffer (Diptera: Ceratopogonidae) in the coastal area of Grosseto: Eeo-ethological aspects. Bull Insectology 60:1\u0026ndash;6\u003c/li\u003e\n \u003cli\u003eRioux JA, Descous S, Corre JJ et al (1968). Ecologie de \u003cem\u003eLeptoconops irritans\u003c/em\u003e No\u0026eacute;, 1905 en moyenne Camargue. Localisation et dynamique des biotopes larvaires. Rev \u0026Eacute;col (La Terre et La Vie) 22(4): 458-469.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"parasitology-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pare","sideBox":"Learn more about [Parasitology Research](http://link.springer.com/journal/436)","snPcode":"436","submissionUrl":"https://submission.nature.com/new-submission/436/3","title":"Parasitology Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"Biting gnats, coastal dune, diurnal pest, landing preferences, Mediterranean islands, Menorca","lastPublishedDoi":"10.21203/rs.3.rs-5453929/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5453929/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eBiting gnats of genus \u003cem\u003eLeptoconops\u003c/em\u003e Skuse 1889 are small blood-feeding insects recognized as highly irritating diurnal pests in certain regions around the globe. In Europe, their presence is poorly documented, except in France and Italy. Following reports of human discomfort in a touristic area of Menorca, Balearic Islands (Spain), a small-scale study was conducted to identify the biting species and assess their preferred biting sites using a human-landing assay along a habitat gradient in a coastal dune area.\u0026nbsp; \u003cem\u003eLeptoconops irritans \u003c/em\u003e(Noé, 1905)\u003cem\u003e \u003c/em\u003ewas identified based on morphological features and DNA barcoding. This species reached high densities (average rates of 3.3 landings/min), particularly near coastal dune vegetation. No statistically significant differences were found among the four main body site landings of \u003cem\u003eL. irritans\u003c/em\u003e (F\u003csub\u003e3,6.023 \u003c/sub\u003e= 1.80, p = 0.250): head (n = 91, 53.8%), lower extremities (n = 39, 23.1%), upper extremities (n = 37, 21.8%) and other covered areas (n = 2, 0.2%). Landing preferences varied among the three volunteers and bites progressed differently. This study represents the second documented case of \u003cem\u003eLeptoconops\u003c/em\u003e gnats causing human discomfort in Spain. We hope this research stimulates further interest in this understudied genus, which has been largely overlooked across much of Europe.\u003c/p\u003e","manuscriptTitle":"Human-biting behavior of Leptoconops irritans (Diptera: Ceratopogonidae) in a touristic area of the Balearic Islands (Spain)","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-18 08:23:25","doi":"10.21203/rs.3.rs-5453929/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2024-12-04T02:22:21+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-12-02T08:51:23+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-11-30T07:46:46+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"204329529539857181122715563720925878105","date":"2024-11-17T13:24:24+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"123685085843354135783020669494306801625","date":"2024-11-15T11:12:26+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-15T07:50:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-11-15T05:08:16+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-11-15T03:26:54+00:00","index":"","fulltext":""},{"type":"submitted","content":"Parasitology Research","date":"2024-11-14T12:31:07+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"parasitology-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pare","sideBox":"Learn more about [Parasitology Research](http://link.springer.com/journal/436)","snPcode":"436","submissionUrl":"https://submission.nature.com/new-submission/436/3","title":"Parasitology Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"5ca03d6d-9118-45fd-bb38-b16198b91b55","owner":[],"postedDate":"December 18th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-02-03T16:06:31+00:00","versionOfRecord":{"articleIdentity":"rs-5453929","link":"https://doi.org/10.1007/s00436-024-08447-z","journal":{"identity":"parasitology-research","isVorOnly":false,"title":"Parasitology Research"},"publishedOn":"2025-01-30 15:57:40","publishedOnDateReadable":"January 30th, 2025"},"versionCreatedAt":"2024-12-18 08:23:25","video":"","vorDoi":"10.1007/s00436-024-08447-z","vorDoiUrl":"https://doi.org/10.1007/s00436-024-08447-z","workflowStages":[]},"version":"v1","identity":"rs-5453929","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5453929","identity":"rs-5453929","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}