Avian louse flies (Hippoboscidae: Ornithomyinae) are blood-feeding parasites with largely unexplored vector potential, although they have been implicated in the transmission of pathogens of medical and veterinary relevance, such as West-Nile virus, Babesia and Trypanosoma species. We screened 253 specimens of nine Ornithomyinae species for selected bacteria (Anaplasma, Rickettsia, Bartonella, Borrelia, and Ehrlichia spp.) as well as for trypanosomes and piroplasms. Anaplasma phagocytophilum was detected in a single Ornithomya avicularia specimen, and Haematospirillum jordaniae was identified in three Ornithomya fringillina individuals from the same location, representing the first report of these bacteria in avian louse flies. In addition, eight different Trypanosoma sequences were obtained, belonging to the T. corvi/culicavium and T. bennetti groups. Unexpectedly, a sequence resembling T. theileri was recovered from an Ornithoica turdi specimen. Our findings suggest that the role of louse flies in transmitting the investigated bacterial pathogens is likely minimal, but their involvement in the ecology of Trypanosoma species warrants further study. Consistent with previous work, we propose that louse flies could serve as valuable sentinels for monitoring pathogens in wild bird populations.

Host-related genetic differentiation of a polyxenic avian ectoparasite, Ornithomya avicularia (Hippoboscidae).

This study presents records of ectoparasitic flies from the family Hippoboscidae collected in Romania between 2022 and 2024. A total of seven species were recorded, with Pseudolynchia canariensis (Macquart in Webb and Berthelot, 1839) representing a new record for the fauna of Romania. To the best of the authors' knowledge, many of the parasite-host associations are new and are previously unpublished. In addition, a graphical network illustrating these associations is provided. This network highlights the frequency and diversity of host-parasite interactions across the study sites. The recorded phoresis of Guimaraesiella (Mallophaga) on Ornithomya avicularia (Linnaeus, 1758) and the hyperparasites Hemimyialges macdonaldi (Evans et al., 1963) and Myialges anchora Sergent and Trouessart, 1907 (both Acariformes: Epidermoptidae) on Ornithoica turdi (Olivier in Latreille, 1811) are newly documented in Romania.

The Hippoboscidae are ectoparasites of birds and mammals, which, as a group, are known to vector multiple diseases. Avipoxvirus (APV) is mechanically vectored by various arthropods and causes seasonal disease in wild birds in the United Kingdom (UK). Signs of APV and the presence of louse flies (Hippoboscidae) on Dunnocks Prunella modularis were recorded over a 16·5-year period in a rural garden in Somerset, UK. Louse flies collected from this site and other sites in England were tested for the presence of APV DNA and RNA sequences. Louse flies on Dunnocks were seen to peak seasonally three weeks prior to the peak of APV lesions, an interval consistent with the previously estimated incubation period of APV in Dunnocks. APV DNA was detected on 13/25 louse flies, Ornithomya avicularia and Ornithomya fringillina, taken from Dunnocks, both with and without lesions consistent with APV, at multiple sites in England. Collectively these data support the premise that louse flies may vector APV. The detection of APV in louse flies, from apparently healthy birds, and from sites where disease has not been observed in any host species, suggests that the Hippoboscidae could provide a non-invasive and relatively cheap method of monitoring avian diseases. This could provide advanced warnings of disease, including zoonoses, before they become clinically apparent.

Changes in climate may cause changes in the ranges, phenology and interactions of insects with other species and lead parasites to switch host species. A study of louse (flat) flies in the United Kingdom, Republic of Ireland and Isle of Man, in which licensed bird ringers acting as citizen scientists collected ectoparasites that left birds during ringing, showed recent range shifts of several species. The Common or Bird Louse Fly Ornithomya avicularia (Linnaeus, 1758), a vector of Haemoproteus sp. and trypanosomes, has undergone a major northwards range expansion of over 300 km in the United Kingdom (UK) since the 1960s. The Finch Louse Fly Ornithomya fringillina (Curtis, 1836) has also expanded its range over 300 km northwards and 400 km westwards into the Island of Ireland, and the Swallow Louse Fly Ornithomya biloba (Dufour, 1827) is now established in Wales and Southern England. The Grouse Louse Fly Ornithomya chloropus (Bergroth, 1901) has undergone a range contraction at lower altitudes and on the southern edge of its range. Other species of louse fly were detected: Crataerina pallida (Latreille, 1812), Stenepteryx hirundinis (Linnaeus, 1758), Pseudolynchia garzettae (Rondani, 1879) and Icosta minor (Bigot, 1858). Some generalist species have shifted their phenology, whereas the more specialist nest parasites of migrant birds have not, as the arrival and breeding dates of their hosts have not changed. The range changes of the generalist species of these ectoparasites may have implications for bird health, especially if they switch to new host species as their ranges shift.

Epidermoptidae (Acariformes: Astigmata) are permanent ectoparasites of birds; representatives of some genera have evolved phoretic associations with louse flies (Hippoboscidae). Moreover, mites of some genera hyperparasitise their phoretic carriers, using them for oviposition and in some cases for feeding. In the course of research focused on bird migrations and avian ectoparasites carried out in Eastern Slovakia in 2022 and 2023, we collected 76 hippoboscid flies of 7 species from 71 birds of 20 species; of these flies, 6 individuals (8 %) were parasitised by epidermoptid mites. Promyialges italicus Faradonbeh et al., 2019 was found on the wings of Ornithomya avicularia (Linnaeus, 1758) and O. biloba Dufour, 1827, both from barn swallow, Hirundo rustica Linnaeus, 1758. Myialges anchora Sergent and Trouessart, 1907 was found on the abdomens of louse flies of three species: Ornithoica turdi (Olivier in Latreille, 1811), Ornithomya fringillina Curtis, 1836, and O. avicularia (Linnaeus, 1758) from the three different avian hosts: Lanius collurio Linnaeus, 1758, Acrocephalus arundinaceus (Linnaeus, 1758), and Turdus merula Linnaeus, 1758, respectively. Promyialges italicus has been recorded on a host other than Pseudolynchia canariensis (Macquart in Webb and Berthelot, 1839) for the first time. Neither species of this mite has been reported in Slovakia.

BackgroundLouse flies (Diptera, Hippoboscidae) are important blood-sucking parasites of birds and mammals with a worldwide distribution. The aim of our study was to collect louse flies from birds across multiple sites in Hungary and evaluate the effects of avian traits on louse fly–host relationships.MethodsBetween 2015 and 2022, 237 louse flies were collected from birds at multiple locations in Hungary. The louse flies were identified to species level by morphological and molecular methods. Louse fly species and their seasonal dynamics were analyzed.ResultsSix louse fly species were identified: Ornithomya avicularia, Ornithomya fringillina, Ornithomya biloba, Ornithomya chloropus, Ornithoica turdi and Ornithoctona laticornis. Results of statistical analyses indicated that habitat, migration habits and the feeding places of birds have significant effects on their possible role as hosts of O. avicularia, O. fringillina and O. turdi. Analysis of the temporal distribution of avian louse flies showed different seasonal patterns according to species. Phylogenetic analyses highlighted that O. turdi clustered separately from other members of the subfamily Ornithomyinae which thus did not form a monophyletic group.ConclusionsThis study presents one of the longest continuous collections of ornithophilic louse fly species in Europe so far. Avian traits were shown to influence louse-fly infestation. To our best knowledge, this is the first report on O. laticornis in Europe. The ability of this African louse fly species to survive in Europe, as demonstrated in the present study, may be an indication of its future establishment. Our findings, in accordance with previous reports, also indicated that the subfamily Ornithomyinae should be taxonomically revised.Graphical

Louse flies (Diptera: Hippoboscidae) are obligatory hematophagous ectoparasites of birds and mammals. These widely distributed parasitic flies may have a significant impact on wild and farm animals by feeding on their blood and transmitting bloodborne pathogens. However, despite their ecological importance, louse flies are clearly underrepresented in host-parasite research and implementation of genetic approaches in this group is generally hampered by lacking molecular tools. In addition, louse flies that parasitize long-distance migrants can travel long distances with their avian hosts, facilitating the large-scale spread of pathogens across landscapes and geographic regions. Given the wide diversity of louse flies that parasitize a variety of avian hosts, their direct negative impact on host survival, and their high potential to transmit bloodborne pathogens even along avian migration routes, it is surprising that our knowledge of louse fly ecology is rather modest and incomplete. Here, we aimed to develop a novel molecular tool for polyxenous avian louse flies from the genus Ornithomya, which are among the most common and widely distributed representatives of Hippoboscidae family, to improve research of their genetic population structure and molecular ecology.Using the Illumina Mi-seq sequencing, we conducted a genome-wide scan in Ornithomya avicularia to identify putative microsatellite markers. A panel of 26 markers was selected to develop amplification protocols and assess polymorphism in the Central European population of O. avicularia, as well as to test for cross-amplification in a congeneric species (O. chloropus).A genome-scan in O. avicularia identified over 12 thousand putative microsatellite markers. Among 26 markers selected for a population-wide screening; one did not amplify successfully and three were monomorphic. 22 markers were polymorphic with at least two alleles detected. Two markers showed presence of null alleles. A cross-amplification of microsatellite markers in O. chloropus revealed allelic polymorphism at 14 loci, with the mean allelic richness of 3.78 alleles per locus (range: 2–8).Our genome-wide scan in O. avicularia provides a novel and powerful tool for molecular research in Ornithomya louse flies. Our panel of polymorphic microsatellite loci should allow genotyping of louse flies from geographically distinct populations and from a wide spectrum of avian hosts, enhancing population genetic and phylogeographic research in Ornithomya.

Las moscas piojo (Diptera: Hippoboscidae) son ectoparásitos permanentes de aves y mamíferos. La abundancia y composición faunística de los hipobóscidos de España está relativamente poco estudiada, con 20 especies registradas hasta el momento. El objetivo de este estudio es aportar datos nuevos sobre estos ectoparásitos a partir de hospedadores aviares recogidos con redes japonesas en dos estaciones de anillamiento del Sistema Central en Madrid (España). Se identificaron cuatro especies generalistas de moscas piojo de la subfamilia Ornithomyinae, obtenidas de 13 hospedadores aviares (Orden: Passeriformes). Estas especies son, en orden de abundancia decreciente: Ornithomya fringillina (Curtis, 1936), Ornithophila metallica (Schiner, 1864), Ornithomya avicularia (Linnaeus, 1758) y Ornithoica turdi (Oliver in Latreille, 1811). El alcaudón común Lanius senator Linnaeus, 1758 fue la especie de ave más comúnmente parasitada por hipobóscidos. Se proporcionan nuevos datos faunísticos e interacciones aves-parásito para España.

The louse fly,Ornithoica momiyamai, is ectoparasitic on a variety of bird species in Japan and the Republic of Korea (ROK). However, its species status has been controversial for many years. We investigated its morphological and ecological traits to clarify further its species status. Morphology of gynandromorphs, which has been regarded as useful in distinguishing related Ornithoica species, was reported for the first time. Gynandromorphs in Japan have a tri-lobed infra-anal plate similar to Ornithoica tridens (endemic to Taiwan) but distinct from several related tropical species. Collection records of O. momiyamai compiled from literature were compared with O. tridens, Ornithoica exilis (a tropical species carried to the temperate region by migratory birds), and Ornithomya avicularia (a Palaearctic species overwintering in the temperate region primary as puparia). The records indicate that O. momiyamai is relatively common throughout temperate Japan and the ROK, found on a number of bird species irrespective of their seasonality, and collected annually and locally if collection efforts are done. Records also document population increases during summer months concurrently with Ornithomya avicularia in warm-temperate Japan. These results demonstrate that O. momiyamai is a temperate species that overwinters as puparia at least in warm-temperate Japan.

In 2017–2020, 3833 birds representing 103 species were captured at two localities in the Lazovsky State Nature Reserve, Primorye Territory, Russian Far East. All birds were ringed and released on site. The research team recorded the presence of louse flies in 646 birds representing 62 species (51 nestlings, 11 migrants), while 41 species from two orders, Charadriiformes and Apodiformes, were found to be uninfested. A total of1184 specimens of louse flies from two subfamilies, Ornithomyinae (3 genera, 6 species) and Lipopteninae (1 genus, 2 species), were revealed. Forty-seven species of birds were recorded to be infested by Ornithoica momiyamai Kishida 1932, most of these serving as hosts new to this louse fly. Forty-two bird species were infested by Ornithomya avicularia (L. 1758) s. l., 11 bird species were found hosts to O. fringillina (Curtis 1856). Ornithoica unicolor Speiser 1900 was revealed on 11 bird species, being the most abundant on the Ural owl (Strix uralensis). Ornithomya comosa (Austen 1930) and Crataerina hirundinis (Curtis 1856) were found on Hirundinidae birds and Parus palustris. Lipoptena cervi (Linnaeus 1758) and L. fortisetosa Maa 1965 were recorded as uncommon bird parasites, as both species were only found on six bird species.

Louse flies (Hippoboscidae) are permanent ectoparasites of birds and mammals. They have a cosmopolitan distribution with more than 200 described species. The aim of this study was to reveal host–vector–parasite associations between louse flies, birds, and trypanosomes. A total of 567 louse fly specimens belonging to 7 species were collected from birds at several localities in Czechia, including the rare species Ornithophila metallica and Ornithoica turdi. There was a significant difference in the occurrence of Ornithomya avicularia and Ornithomya fringillina on bird hosts according to their migratory status, O. fringillina being found more frequently on long-distance migrants. Trypanosomes were found in four species, namely, Ornithomya avicularia, O. fringillina, O. biloba, and Ornithoica turdi; the later three species are identified in this paper as natural trypanosome vectors for the first time. The prevalence of trypanosomes ranged between 5 and 19%, the highest being in O. biloba and the lowest being in O. fringillina. Phylogenetic analysis of the SSU rRNA gene revealed that a vast majority of trypanosomes from hippoboscids belong to the avian T. corvi/culicavium group B. Four new lineages were revealed in group B, with louse flies being probable vectors for some of these trypanosome lineages. We also confirmed the transcontinental distribution of several trypanosome lineages. Our results show that hippoboscids of several genera are probable vectors of avian trypanosomes.

Ectoparasites such as louse flies (Diptera: Hippoboscidae) have tendency for host specialization, which is driven by adaptation to host biology as well as competition avoidance between parasites of the same host. However, some louse fly species, especially in genera attacking birds, show wide range of suitable hosts. In the presented study, we have surveyed the current status of bird specific louse flies in Finland to provide comprehensive host association data to analyse the ecological requirements of the generalist species. A thorough sampling of 9342 birds, representing 134 species, recovered 576 specimens of louse flies, belonging to six species: Crataerina hirundinis, C. pallida, Ornithomya avicularia, O. chloropus, O. fringillina and Ornithophila metallica. Despite some overlapping hosts, the three Ornithomya species showed a notable pattern in their host preference, which was influenced not only by the host size but also by the habitat and host breeding strategy. We also provide DNA barcodes for ten Finnish species of Hippoboscidae, which can be used as a resource for species identification as well as metabarcoding studies in the future.

Ectoparasites such as louse flies (Diptera: Hippoboscidae) have tendency for host specialization, which is driven by adaptation to host biology as well as competition avoidance between parasites of the same host. However, some louse fly species, especially in genera attacking birds, show wide range of suitable hosts. In the presented study, we have surveyed the current status of bird specific louse flies in Finland to provide comprehensive host association data to analyse the ecological requirements of the generalist species. A thorough sampling of 9342 birds, representing 134 species, recovered 576 specimens of louse flies, belonging to six species: Crataerina hirundinis, C. pallida, Ornithomya avicularia, O. chloropus, O. fringillina and Ornithophila metallica. Despite some overlapping hosts, the three Ornithomya species showed a notable pattern in their host preference, which was influenced not only by the host size but also by the habitat and host breeding strategy. We also provide DNA barcodes for ten Finnish species of Hippoboscidae, which can be used as a resource for species identification as well as metabarcoding studies in the future.

This study aims to assess the occurrence of external arthropods on deceased raptors in rescue centers in Tuscany, central Italy. The examined diurnal raptors include 17 common buzzards (Buteo buteo), two European honey buzzards (Pernis apivorus), seven sparrowhawks (Accipiter nisus), six common kestrels (Falco tinnunculus), a western osprey (Pandion haliaetus), and a peregrine falcon (Falco peregrinus). Nocturnal raptors included seven barn owls (Tyto alba), ten tawny owls (Strix aluco), 22 little owls (Athene noctua) and two scops owls (Otus scops). The skin and the feathers of each animal were examined, and arthropods were collected, fixed, and microscopically identified. In 48 out of the 75 examined birds (64%), at least a single arthropod species was found. Identified arthropods included chewing lice (Degeeriella fulva, D. rufa, Colpocephalum turbinatum, C. apivorus, Nosopon lucidum, N. clayae, Craspedorrhyncus platystomus, Laemobothrion tinnunculi, Kurodaia subpachygaster, Strigiphilus cursitans), hippoboscid flies (Ornithomya avicularia), chigger and feather mites (Kramerella lunulata, K. lyra, Kramerella sp., Glaucalges attenuatus, Hieracolichus nisi, Hieracolichus sp., Neotrombicula autumnalis) and ticks (Haemaphysalis sp.). Most of the identified mite, fly and tick species are the first records in raptors in Italy. Moreover, this study presents the first record of Hieracolichus sp. and N. autumnalis mites in P. haliaetus and F. tinnunculus, respectively.

A Promyialges pari Fain, 1965 (Analgoidea: Epidermoptidae) feather mite was found on the louse fly Ornithomya avicularia L., 1758 (Diptera: Hippoboscidae), recovered from Eurasian rook, Corvus frugillegus L., 1758 (Passeriformes: Corvidae), in the south of European Russia. This is the first record of P. pari in Russia and on the aforementioned bird host.

Between 2012 and 2018 a total of 2094 individual birds representing 265 species (168 passeriformes and 97 non-passeriformes), 70 families (32 passeriformes and 38 non-passeriformes) and 21 orders were sampled for louse-flies and other ectoparasites in different locations in all nine provinces of South Africa. A total of 153 louse-flies of six genera and 16 taxa were recorded: Crataerina acutipennis, Icosta meda, I. minor, I. pilosa, Icosta sp. 1–3, Ornithoica turdi, Ornithoica sp. 1, Ornithomya avicularia, O. biloba, O. fur, Ornithophila metallica, Pseudolynchia canariensis, P. garzettae and Pseudolynchia sp. Louse-flies were found on 137 birds (prevalence 6.5 %) of 78 species from 11 orders. In total we report 93 host-parasite associations of which 84 are reported here for the first time. We found statistically significant higher prevalence and mean abundance of louse-flies in autumn and spring. However, mean intensity was not different between the four seasons. Cases of phoresy of chewing lice, fungal infection and mite infestations of flies are reported and discussed. Available sequences of COI, EF and 16S rRNA genes of examined genera of louse-flies were used in order to assess relative genetic divergence among louse-fly populations.

Eight species of louse flies were recorded on 22 bird species as the result of research carried out in 2008–2018 in Voronezh Province of Russia. Five species are reported from the region for the first time: Ornithomya fringillina (Curtis, 1836), O. chloropus (Bergroth, 1901), Ornithoica turdi (Olivier in Latreille, 1811), Ornithophila metallica (Schiner, 1864), and Icosta ardeae (Macquart, 1835). Five species reproduce and complete their life cycles in the region: Crataerina hirundinis (Linnaeus, 1758), C. pallida (Olivier in Latreille, 1812), Ornithomya avicularia (Linnaeus, 1758), O. fringillina, and O. chloropus; the remaining 3 species are introduced into the region by migratory birds: Icosta ardeae, Ornithoica turdi, and Ornithophila metallica. The predominant species are Ornithomya avicularia (42.29%), O. fringillina (29.57%), and C. hirundinis (12.56%). Crataerina hirundinis and C. pallida are monoxenous, I. ardeae is oligoxenous, and the remaining species are polyxenous parasites of birds. All louse fly species were found on adult birds and nestlings in April–May, while C. hirundinis was also common on the second-brood nestlings in August–September.

In Voronezh, 14 species of parasitic insects were found in sparrows and their nests during 2017–2020. It was found 6 species of chewing lice: Menacanthus eurysternus Giebel, 1874, Ricinus fringillae De Geer, 1778, Sturnidoecus ruficeps Giebel, 1866, Brueelia subtilis Giebel, 1874, B. borini Lunkaschu, 1970, and Philopterus montani Zlotorzycka, 1964. Among them, Menacanthus eurysternus was the dominant species for the House Sparrow (dominance 21.70 %, prevalence 10.00) while B. subtilis (dominance 18.60 %, prevalence 8.00) and B. borini (dominance 16.29 %, prevalence 6.00) were subdominant. For the European Tree Sparrow, the dominant species were B. borini (dominance 22.07 %, prevalence 8.00) and Ph. montani (dominance 22.07 %, prevalence 10.6). All six chewing lice species were observed for the first time in Voronezh and the Central Black Soil Region of Russia. Three species of fleas – Ceratophillus gallinae (Schrank, 1803), C. fringillae Walker, 1856, and C. tribulus Jordan, 1926) – were registered. The dominant flea species was C. gallinae (for the House Sparrow, dominance was 67.13 %, prevalence 45.00; for the Tree Sparrow, dominance was 66.47 %, prevalence 73.33). Abundance of fleas for House Sparrow nestlings was 0.724, and 1.153 for Tree Sparrow nestlings. Parasitic flies were represented by five species: Ornithomya avicularia (Linnaeus, 1758), O. fringillina Curtis, 1836, O. chloropus Bergroth 1901 (Hippoboscidae), Protocalliphora azurea Fll., 1817, and Trypocalliphora braueri (Hendel, 1901) (Calliphoridae). Among louse flies O. avicularia was the dominant species (for House sparrow, dominance was 85.93 %, prevalence 53.00; for Tree Sparrow, dominance was 68.64 %, prevalence 20.00). Larvae of P. azurea were found in 13.00 % of House Sparrow nests and in 15.00 % of Tree Sparrow nests. For House Sparrow nestlings, intensity was 3.42 % with abundance 0.30, while for Tree Sparrow nestlings, intensity was 0.15 % with abundance 2.05. Larvae of T. braueri were found in 31.00 % of House Sparrow nests and in 40.00 % of Tree Sparrow nests. For House Sparrow nestlings, intensity was 0.164 with abundance 0.088. For Tree Sparrow nestlings, intensity was 0.106 with abundance 0.220. Significant fluctuations of prevalence and abundance of the larvae in different years were found.

Louse flies (Diptera, Hippoboscidae) were collected off 38 species of birds from 16 genera of 14 families and 5 orders. Birds were captured in large funnel traps and mist nets on the Courish Spit (Kaliningrad Province, Russia). Five species of ornithophilic louse flies were found: Ornithomya avicularia (Linnaeus, 1758), O. chloropus (Bergroth, 1901), O. fringillina (Curtis, 1856), O. comosa (Austen, 1930), and Crataerina hirundinis (Linnaeus, 1758); besides, the mammalophilic species Lipoptena fortisetosa (Maa, 1965) was recorded on a non-specific bird host. The association of louse flies with their hosts, infestation parameters, collection data, and general geographic distribution of the recorded louse fly species are considered. The overall infestation of birds with louse flies was low. The louse fly fauna of Kaliningrad Province is compared with the faunas of the adjacent territories.