Ultrastructural characterization of sensilla and microtrichia on the antenna of female Haematopota pandazisi (Diptera: Tabanidae).

The haematophagous females of the cleg fly Haematopota pandazisi (Kröber) (Diptera: Tabanidae) are a common pest in areas inhabited by wild and domestic ungulates in southern Europe, North Africa and Anatolia. A morphological investigation by scanning electron microscopy (SEM) was carried out for the first time on the antennae of females of H. pandazisi, with special attention to the type and distribution of sensilla and microtrichia. The typical brachyceran antenna is divided into three regions: the scape, the pedicel and the flagellum, which is the longest of the three and is composed of four flagellomeres. The scape and pedicel are characterized by only one type of microtrichium and chaetic sensillum, whereas five types of microtrichia and sensilla were identified on the flagellum and classified according to shape and distribution. The sensilla are of the chaetic, clavate, basiconic, trichoid and coeloconic types; the latter with either a basiconic or grooved peg inside. The results obtained in this study were compared to those found in other species in the family Tabanidae and other Diptera, with special attention to haematophagous species.

An Overview of Tick-Borne Encephalitis Epidemiology in Endemic Regions of Continental Croatia, 2017-2023.

Tick-borne encephalitis (TBE) represents an important public health problem in Europe. We analyzed the epidemiology of TBE based on data from humans, animals, and Ixodes ricinus ticks in endemic regions of continental Croatia. In the period from 2017 to 2023, cerebrospinal fluid (CSF) and serum samples of 684 patients with neuroinvasive diseases, 2240 horse serum samples, and 300 sheep serum samples were tested for TBEV. In addition, 8751 I. ricinus ticks were collected. CSF samples were tested using RT-PCR. Serological tests (serum, CSF) were performed using commercial ELISA, with confirmation of cross-reactive samples by a virus neutralization test. Eighty-four autochthonous human TBEV cases were confirmed. The majority of patients were in the age group of 40-69 years (58.3%) with a male predominance (70.2%). TBE showed a bimodal seasonality with a large peak in April-August and a small one in October-November. In addition to humans, TBEV IgG antibodies were found in 12.2% of horses and 9.7% of sheep. Seasonal tick abundance corresponds to the reported number of human infections. Continental Croatia is still an active natural focus of TBE. Continuous monitoring of infections in humans, sentinel animals, and ticks is needed for the implementation of preventive measures.

Diversity of flesh flies (Sarcophagidae, Sarcophaginae) of pond habitats in rural areas in the Croatian part of Baranja.

The diversity of grey flesh flies (Sarcophagidae: Sarcophaginae) from the Croatian part of Baranja was studied during 2019 to 2021, resulting in 37 species, of which the following are new for the area: Raviniapernix (Harris, 1780); Sarcophaga (Het.) depressifrons Zetterstedt, 1845; S. (Het.) filia Rondani, 1860; S. (Het.) haemorrhoides Böttcher, 1913; S. (Het.) pumila Meigen, 1826; S. (Het.) vagans Meigen, 1826; S. (Lis.) dux Thomson, 1869; S. (Lis.) tuberosa Pandellé, 1896; S. (Meh.) sexpunctata (Fabricius, 1805); S. (Pan.) protuberans Pandellé, 1896; S. (Sar.) carnaria (Linnaeus, 1758); S. (Sar.) variegata (Scopoli, 1763), and S. (Pse.) spinosa Villeneuve, 1912. New locality records are provided for 25 species. Sarcophaga (Sar.) croatica Baranov, 1941 was the most abundant with 37%, followed by S. (Sar.) lehmanni Müller, 1922 (21%), and S. (Pas.) albiceps Meigen, 1826 (5%), making up 63% of all collected specimens. Most species (35) were collected in locality of Zmajevac, while the fewest (3) were collected in Bilje locality. During this study, S. (Pse.) spinosa was recorded in Croatia for the first time. Combined with previous records, 42 species of flesh flies have been recorded from Croatian Baranja, which comprise 27% of the flesh flies known to occur in Croatia. The total number of species of the family Sarcophagidae currently known in Croatia has increased to 156.

Current Status of Vector-Borne Diseases in Croatia: Challenges and Future Prospects.

Different vector-borne pathogens are present or have (re-)emerged in Croatia. Flaviviruses tick-borne encephalitis (TBEV), West Nile (WNV), and Usutu (USUV) are widely distributed in continental regions, while Toscana virus (TOSV) and sandfly fever viruses are detected at the Croatian littoral. Recently, sporadic clinical cases of Tahyna orthobunyavirus (TAHV) and Bhanja bandavirus infection and seropositive individuals have been reported in continental Croatia. Acute infections and serologic evidence of WNV, TBEV, USUV, and TAHV were also confirmed in sentinel animals and vectors. Autochthonous dengue was reported in 2010 at the Croatian littoral. Lyme borreliosis is the most widely distributed vector-borne bacterial infection. The incidence is very high in northwestern and eastern regions, which correlates with numerous records of Ixodes ricinus ticks. Acute human Anaplasma phagocytophilum infections are reported sporadically, but there are many records of serologic evidence of anaplasmosis in animals. Mediterranean spotted fever (Rickettsia conorii) and murine typhus (Rickettsia typhi) are the main rickettsial infections in Croatia. Human leishmaniasis is notified sporadically, while serologic evidence of leishmaniasis was found in 11.4% of the Croatian population. After the official eradication of malaria in 1964, only imported cases were reported in Croatia. Since vector-borne diseases show a growing trend, continuous monitoring of vectors is required to protect the population from these infections.

Detection of Bhanja Bandavirus in Patients with Neuroinvasive Disease of Unknown Etiology in Croatia.

BACKGROUND: Although the Bhanja bandavirus (BHAV) is widely distributed in some European countries, human infections are rarely reported. This study analyzed the prevalence of BHAV antibodies in patients with neuroinvasive diseases of unsolved etiology. METHODS: A total of 254 Croatian patients who developed neurological symptoms during the four consecutive arbovirus transmission seasons (April 2017-October 2021) were tested. Cerebrospinal fluid (CSF) and urine samples were tested using RT-qPCR. In addition, CSF and serum samples were tested using a virus neutralization test. RESULTS: BHAV RNA was not detected in any samples, while neutralizing (NT) antibodies were detected in serum samples of 53/20.8% of patients (95% CI = 16.0-26.3). In two patients, BHAV NT antibodies were detected in the CSF, indicating a recent infection. Both patients were inhabitants of rural areas in continental Croatia, and one reported a tick bite two weeks before symptoms onset. The seropositivity was high in all age groups (15.2-29.1%). The majority of seropositive patients (94.3%) resided at altitudes less than 200 m above sea level. The prevalence rates correlated positively with population density and negatively with certain climate parameters (temperature, number of hot/warm days). CONCLUSIONS: The presented results indicate that BHAV is distributed in Croatia. Further studies are needed to determine the clinical significance of this neglected arbovirus.

Dermacentor reticulatus - a tick on its way from glacial refugia to a panmictic Eurasian population.

The ornate dog tick (Dermacentor reticulatus) shows a recently expanding geographic distribution. Knowledge on its intraspecific variability, population structure, rate of genetic diversity and divergence, including its evolution and geographic distribution, is crucial to understand its dispersal capacity. All such information would help to evaluate the potential risk of future spread of associated pathogens of medical and veterinary concern. A set of 865 D. reticulatus ticks was collected from 65 localities across 21 countries, from Portugal in the west to Kazakhstan and southern Russia in the east. Cluster analyses of 16 microsatellite loci were combined with nuclear (ITS2, 18S) and mitochondrial (12S, 16S, COI) sequence data to uncover the ticks' population structures and geographical patterns. Approximate Bayesian computation was applied to model evolutionary relationships among the found clusters. Low variability and a weak phylogenetic signal showing an east-west cline were detected both for mitochondrial and nuclear sequence markers. Microsatellite analyses revealed three genetic clusters, where the eastern and western cluster gradient was supplemented by a third, northern cluster. Alternative scenarios could explain such a tripartite population structure by independent formation of clusters in separate refugia, limited gene flow connected with isolation by distance causing a "bipolar pattern", and the northern cluster deriving from admixture between the eastern and western populations. The best supported demographic scenario of this tick species indicates that the northern cluster derived from admixture between the eastern and western populations 441 (median) to 224 (mode) generations ago, suggesting a possible link with the end of the Little Ice Age in Europe.

DNA barcoding of the horsefly fauna (Diptera, Tabanidae) of Croatia with notes on the morphology and taxonomy of selected species from Chrysopsinae and Tabaninae.

In the Croatian fauna, horseflies (Tabanidae) are represented by 78 species belonging to two subfamilies, five tribes, and 10 genera. Identification of these species is based on morphological characteristics. In this study, 43 species of horseflies were analyzed. The highest number of species (19) belongs to the genus Tabanus, followed by the genera Hybomitra with seven species, Haematopota with six species, Chrysops with four species, Atylotus and Philipomyia with two species each, and the genera Silvius, Dasyrhamphis, and Heptatoma with one species each. The standard DNA barcoding region of the mitochondrial cytochrome c oxidase gene, subunit I (COI), was sequenced and compared to the Barcode of Life Database (BOLD). Our analyses confirmed our morphological identifications and added 16 new Barcode Index Numbers (BINs) for Tabanidae to BOLD. Potential problems in the systematics and taxonomy of this family are highlighted.

Lucilia sericata (Diptera: Calliphoridae) as Agent of Myiasis in a Goose in Italy and a Review of Myiasis by This Species in Birds.

Myiasis is a type of parasitosis by larvae of Diptera that may affect vertebrates, including wild and domestic birds. Traumatic myiasis was discovered in a domestic goose, Anser anser domesticus L. (Anseriformes: Anatidae), in June 2020 in a rural area of the region Calabria (Southern Italy). The myiasis was caused by Lucilia sericata (Meigen) (Diptera: Calliphoridae). In Italy, this was the first case of myiasis by L. sericata ever described in a bird. It was also the first case of myiasis detected in a goose in Italy. The description of the case is integrated by a discussion on nonhematophagous dipteran larvae causing myiasis in birds and by an updated and detailed review of literature cases of myiasis by L. sericata in birds reported worldwide, useful for monitoring and management of dipteran species of medical and veterinary interest.

DNA barcoding of hard ticks (Ixodidae), notes on distribution of vector species and new faunal record for Croatia.

Molecular methods are increasingly being utilized for accurate identification of ticks (Acari: Ixodidae), especially in cases of morphologically highly similar species. In this study, we performed molecular research of the tick fauna in Croatia using DNA barcoding method. Ticks were sampled in three biogeographical regions and thirteen species were recorded: Dermacentor marginatus, Dermacentor reticulatus, Haemaphysalis concinna, Haemaphysalis inermis, Haemaphysalis punctata, Hyalomma marginatum, Ixodes frontalis, Ixodes hexagonus, Ixodes kaiseri, Ixodes ricinus, Rhipicephalus bursa, Rhipicephalus sanguineus s.l. and Rhipicephalus turanicus. Ixodes kaiseri is for the first time recorded in the fauna of Croatia. Of the thirteen hard tick species analyzed in this study, pathogens from different groups (bacteria, protozoa and viruses) have been detected in eight species in Croatia so far. For the important vector species R. sanguineus s.s., new distributional data for Croatia are given. The standard COI barcoding region was amplified, and the sequences were analyzed by species delimitation methods together with the sequences of conspecific and congeneric species from the public BOLD database. Our specimens of H. punctata represent a new, genetically distinct MOTU. A brief overview of the available public DNA barcoding data for Ixodidae is presented, highlighting the need for an integrative approach for the clarification of the taxonomic status of problematic Ixodid taxa. The results provide a basis for the establishment of a molecular data platform for the Ixodidae of the Croatian fauna.

Emerging and Neglected Viruses of Zoonotic Importance in Croatia.

Several arboviruses have emerged in Croatia in recent years. Tick-borne encephalitis is endemic in continental counties; however, new natural micro-foci have been detected. Two autochthonous dengue cases were reported in 2010. West Nile virus emerged in 2012, followed by emergence of Usutu virus in 2013. Although high seroprevalence rates of Toscana virus have been detected among residents of Croatian littoral, the virus remains neglected, with only a few clinical cases of neuroinvasive infections reported. Lymphocytic choriomeningitis virus is a neglected neuroinvasive rodent-borne virus. So far, there are no reports on human clinical cases; however, the seroprevalence studies indicate the virus presence in the Croatian mainland. Puumala and Dobrava hantaviruses are widely distributing rodent-borne viruses with sporadic and epidemic occurrence. Hepatitis E virus is an emerging food-borne virus in Croatia. After the emergence in 2012, cases were regularly recorded. Seropositivity varies greatly by region and population group. Rotaviruses represent a significant healthcare burden since rotavirus vaccination is not included in the Croatian national immunization program. Additionally, rotaviruses are widely distributed in the Croatian ecosystem. A novel coronavirus, SARS-CoV-2, emerged in February 2020 and spread rapidly throughout the country. This review focuses on emerging and neglected viruses of zoonotic importance detected in Croatia.

Diversity, ecology, and seasonality of hard ticks (Acari: Ixodidae) in eastern Croatia.

The diversity of hard tick fauna was studied in different forest communities in 48 localities of eastern Croatia using the dragging-flagging method and by hand from ten different vertebrate hosts. A total of 2,225 specimens comprising seven species in three genera were identified. Ixodes ricinus, the most abundant species (72.8% of all collected specimens) was recorded in 44 localities, followed by Dermacentor reticulatus in 19 localities, while the other five species (D. marginatus, H. concinna, H. inermis, I. canisuga, and I. hexagonus) were recorded in fewer localities. The highest ratio (67% of collected ticks) was in the adult stage with the predominance of females. The numbers of collected females, males, and nymphs of I. ricinus and H. concinna differed significantly. Ten new tick-host associations in Croatia were recorded. Fifty-three animals were infested with one tick species. Single species infestation with I. ricinus was found in 45.8% of animals, followed by D. reticulatus with 25.4%, D. marginatus with 10.2%, H. inermis and I. hexagonus with 3.4%, and I. canisuga with 1.7%. Coinfestation with two species of ticks were recorded in six animals. Ixodes ricinus, H. inermis, and D. reticulatus showed bimodal seasonal activity; for other species unimodal activity patterns were recorded.

Checklist of the Sarcophagidae (Diptera) of Croatia, with new records from Croatia and other Mediterranean countries.

An updated checklist of Croatian flesh flies is presented based on the literature, on material collected from 2004 to 2017, and on specimens in museum collections. The checklist comprises 22 genera and 148 species (two left unnamed), 105 of which are represented by new Croatian records. Twenty-five species are recorded from Croatia with certainty for the first time: Amobiapelopei (Rondani, 1859), Apodacraseriemaculata Macquart, 1854, Craticulinatabaniformis (Fabricius, 1805), Macronychiastriginervis (Zetterstedt, 1838), Metopiacampestris (Fallén, 1810), Miltogrammabrevipila Villeneuve, 1911, Miltogrammaiberica Villeneuve, 1912, Miltogrammaoestracea (Fallén, 1820), Miltogrammapunctata Meigen, 1824, Oebalia cylindrica (Fallén, 1810), Phyllotelespictipennis Loew, 1844, Senotainiaconica (Fallén, 1810), Taxigrammahilarella (Zetterstedt, 1844), Taxigrammastictica (Meigen, 1830), Agriamonachae (Kramer, 1908), Nyctialugubris (Macquart, 1843), Blaesoxipha (Blaesoxipha) aurulenta Rohdendorf, 1937, Blaesoxipha (Blaesoxipha) batilligera Séguy, 1941, Blaesoxipha (Blaesoxipha) plumicornis (Zetterstedt, 1859), Sarcophaga (Helicophagella) okaliana (Lehrer, 1975), Sarcophaga (Heteronychia) amita Rondani, 1860, Sarcophaga (Heteronychia) ancilla Rondani, 1865, Sarcophaga (Heteronychia) pseudobenaci (Baranov, 1942), Sarcophaga (Myorhina) lunigera Böttcher, 1914 and Sarcophaga (Stackelbergeola) mehadiensis Böttcher, 1912. Taxigrammahilarella, Nyctialugubris, Agriamonachae, Blaesoxipha (Blaesoxipha) aurulenta and Sarcophaga (Heteronychia) amita are recorded from Southeast Europe with certainty for the first time. The species Sarcophaga (Sarcophaga) hennigi Lehrer, 1978 is omitted from the list, as previous records from Croatia are shown to be based on an erroneous synonymy with Sarcophaganovaki Baranov, 1941 (= Sarcophaga (Sarcophaga) croatica Baranov, 1941). Blaesoxipha (Blaesoxipha) rufipes (Macquart, 1839) could not be confirmed from Croatia and is not included in the checklist. Three new synonymies are proposed: Golania Lehrer, 2000 = Thyrsocnema Enderlein, 1928, syn. nov., Parasarcophaga (Liosarcophaga) kovatschevitchi Strukan, 1970 = Sarcophaga (Liosarcophaga) marshalli Parker, 1923, syn. nov., and Sarcophagasubvicinassp.novaki Baranov, 1941 = Sarcophaga (Sarcophaga) croatica Baranov, 1941, syn. nov. As part of an effort to update the European distributions of all Croatian species, the following new national and regional records are also provided: Miltogrammabrevipila, Miltogrammataeniata Meigen, 1824 and Sarcophaga (Heteronychia) pandellei (Rohdendorf, 1937) new to Greece; Sarcophaga (Liosarcophaga) harpax Pandellé, 1896 and Sarcophaga (Sarcophaga) croatica new to Italy (respectively mainland and mainland and Sicily); Miltogrammaiberica new to Bulgaria and Sardinia; Pterellaconvergens (Pandellé, 1895) new to mainland Italy and Sicily; Nyctialugubris new to mainland Italy and Sardinia; Blaesoxipha (Blaesoxipha) litoralis (Villeneuve, 1911) new to Sardinia and thus confirmed for Italy; Apodacraseriemaculata, Macronychiastriginervis, Protomiltogrammafasciata (Meigen, 1824) and Blaesoxipha (Blaesoxipha) ungulata (Pandellé, 1896) new to Sardinia and Sicily; Macronychiadolini Verves & Khrokalo, 2006, Macronychiapolyodon (Meigen, 1824), Metopiaargyrocephala (Meigen, 1824), Senotainiaalbifrons (Rondani, 1859), Taxigrammamultipunctata (Rondani, 1859), Taxigrammastictica, Blaesoxipha (Blaesoxipha) unicolor (Villeneuve, 1912) and Sarcophaga (Helicophagella) agnata Rondani, 1860 new to Sardinia; Metopodiapilicornis (Pandellé, 1895), Miltogrammaoestracea, Miltogrammarutilans Meigen, 1824, Nyctiahalterata (Panzer, 1798), Blaesoxipha (Blaesoxipha) lapidosa Pape, 1994 and Blaesoxipha (Blaesoxipha) plumicornis new to Sicily.

Myiasis in domestic cats: a global review.

Myiasis is an infestation caused by larvae of Diptera in humans and other vertebrates. In domestic cats, Felis silvestris catus L. (Carnivora: Felidae), four dipteran families have been reported as agents of obligatory and facultative myiasis: Oestridae, Calliphoridae, Sarcophagidae and Muscidae. Among agents of obligatory myiasis, the most frequent genus is Cuterebra Clark (Oestridae) and the most frequent species is Cochliomyia hominivorax (Coquerel) (Calliphoridae). Among the agents of facultative myiasis, the most frequent species is Lucilia sericata (Meigen) (Calliphoridae). A survey of myiasis in cats reported in literature shows that the cases are distributed worldwide and linked to the geographical range of the dipteran species. Factors favouring the occurrence of myiasis in cats are prowling in infested areas, poor hygiene conditions due to diseases and/or neglect, and wounds inflicted during territorial or reproductive competition. The aim of the review is to provide an extended survey of literature on myiasis in cats, as general information and possible development of guidelines for veterinarians, entomologists and other researchers interested in the field.

Horse flies (Tabanidae) of Bosnia and Herzegovina.

The horse fly (Diptera: Tabanidae) fauna of Bosnia and Herzegovina consists of 62 species belonging to ten genera. The present study adds eight new records for the fauna of Bosnia and Herzegovina. These new records are Chrysops flavipes Meigen, Hybomitra tropica (Linnaeus), Tabanus darimonti Leclercq, Tabanus eggeri Schiner, Tabanus miki Brauer in Brauer and Bergenstamm, Tabanus shannonellus Kröber, Haematopota bigoti Gobert, and Haematopota subcylindrica Pandellé. Most of the species belong to the Boreal-Eurasian group (28), followed by the Mediterranean group with 17 species, the South European group with 13 species, the Afro-Eurasian arid group and the European group with two species each. This paper presents the first comprehensive collection data on the horse fly fauna of this part of the Balkan Peninsula.

Responses of Tabanidae (Diptera) to canopy traps baited with 4-methylphenol, 3-isopropylphenol, and naphthalene.

The attraction of female tabanids to unbaited and single-baited canopy traps using 4-methylphenol, 3-isopropylphenol, and naphthalene was studied in three forest localities in eastern Croatia. Tabanids were collected in a significantly higher number in traps baited with these chemicals compared to unbaited control traps. The number of females of Tabanus bromius, Tabanus sudeticus, Tabanus tergestinus, Hybomitra ciureai, Haematopota pluvialis, and Tabanus maculicornis collected from 4-methylphenol baited canopy traps and traps baited with other attractants differed significantly. A total of 89.0% of tabanids collected belonged to these six species. The response of the other species to used chemicals was not analyzed because of small sample sizes. Moreover, the results with 3-isopropylphenol and naphthalene are very similar and not significant for some tabanids. Tabanus bromius was the most abundant species with 48.4% in the sample collected by canopy traps. Finally, the 4-methylphenol baited canopy traps collected 16 times more tabanids than unbaited traps, while 3-isopropylphenol and naphthalene baited traps collected 3.5 and 2 times as many tabanids, respectively, than unbaited traps. Also, 4-methylphenol appeared to be a very effective attractant for Lucilia caesar (Calliphoridae), Sarcophaga carnaria (Sarcophagidae), and Musca domestica (Muscidae).

Analysis of fibroblast growth factor influence on growth and developmental potential of rat foetuses in the in vitro culture model.

The fibroblast growth factor's (FGF) influence on the growth and differentiation of 8- and 9- day-old rat foetus has been studied, whereas foetuses were grown in an in vitro culture model. Proliferation was analysed by the expression of proliferating cell nuclear antigen (PCNA). It was established that the usage of FGF in the first period of the culture lowers the growth no matter the foetus age at the moment of culturing and no matter whether it is a medium with or without a serum. If FGF is applied in the second culture period, it also lowers the growth, however younger foetuses in the in vitro culture model are more sensible to FGF negative influence. When FGF was applied in a lower concentration the growth of whole foetuses was improved in the in vitro culture model, which shows that the FGF influence on growth depends on the concentration. Stereological analyses have been done and showed that, in the in vitro culture model, FGF has no influence on proliferating cartilage tissue, but it stimulates the survival of nervel tissue cells. It has been shown that the quantitative research of growth processes in cultivated foetuses can precisely be done by combining classic methods of measuring whole foetus diameters and analysing the expression of proliferating antigen.

First record of Aedes albopictus in Croatia.

The first record of Aedes albopictus in Croatia was made in Zagreb, Croatia, on October 28, 2004. A total of 13 larvae were collected in a discarded ceramic toilet bowl in a forested area in the southwest suburbs. Because the winter temperatures in Zagreb are not favorable for survival, this finding of Ae. albopictus may be temporary. Its survival in northern Croatia remains to be studied.

Response of Tabanidae (Diptera) to different natural attractants.

The response of female tabanids to natural attractants was studied in the Monjoros Forest along the Nature Park Kopacki rit in eastern Croatia. Tabanids were caught in canopy traps baited with either aged cow, horse, sheep, or pig urine and also in unbaited traps. Tabanids were collected in a significantly higher numbers in traps baited with natural attractants compared to unbaited traps. The number of females of Tabanus bromius, Tabanus maculicornis, Tabanus tergestinus, and Hybomitra bimaculata collected from canopy traps baited with cow urine and traps baited with other natural attractants differed significantly. Females of Haematopota pluvialis were also collected more frequently in canopy traps baited with aged cow urine than in those with aged horse urine, but this difference was not significant. However, the number of females of Haematopota pluvialis collected from canopy traps baited with other natural attractants (sheep and pig urine) differed significantly when compared with aged cow urine baited traps. Canopy traps baited with aged cow urine collected significantly more Tabanus sudeticus than did traps baited with aged pig urine. Finally, the aged cow urine baited canopy traps collected 51 times more tabanids than unbaited traps, while aged horse, aged sheep, and aged pig urine baited traps collected 36, 30, and 22 times as many tabanids, respectively, than unbaited traps.

Analysis of the feeding sites for some horse flies (Diptera, Tabanidae) on a human in Croatia.

The landing patterns of horse flies on the human body were observed in Croatia. A total of 386 horse flies belonging to 22 species were sampled. The five most commonly collected species were used in the analysis. The stochastic linear connection is tight among the landings of the species Tabanus bromius, Tabanus maculicornis, Tabanus tergestinus, and Philipomyia graeca on the human body regions (matrix R). The preferred feeding area for these four species was the lower leg, whereas for the species Haematopota pluvialis it was the head and neck. Of the total number of horse flies that landed 44.81% were on the lower leg. Only 0.26% landed on the forearm. Chi-square analysis indicated non random landing patterns on human by these horse flies.

Seasonal abundance of horse flies (Diptera: Tabanidae) from two locations in eastern Croatia.

A total of 10,539 tabanid horse flies from 22 species and five genera was collected in the Tikves forest within the Kopacki rit Nature Park in eastern Croatia. Seasonal abundance was analyzed for the six most abundant species. Tabanus maculicornis, Tabanus tergestinus, and Haematopota pluvialis reached their highest peak abundance in the fourth week of June. Atylotus loewianus and Tabanus bromius reached their highest peak of abundance in the first week of August, whereas Tabanus sudeticus reached its maximum abundance in the third week of July. Horse flies also were collected once a week on the pasture at Petrijevci from mid-May to mid-September during 1993. Paired collections were made from a Malaise trap and from a horse by using a sweep net. A total of 2,867 tabanids belonging to 26 species was collected. The number of tabanids collected on horses was much higher than the total captured with Malaise traps. On their natural host (horse), 2.6 times more tabanids were collected than in the traps. Seasonal abundance was analyzed only for the eight most abundant species. Chrysops paralellogrammus, Tabanus autumnalis, Tabanus bromius, Tabanus tergestinus, Haematopota pluvialis, and Haematopota subcylindrica all reached their highest peak of abundance in the second week of July, whereas Tabanus maculicornis reached the maximal peak of abundance in the third week of June. Seasonal meteorological variability that occurs periodically from one year to another has a significant influence on the maximal peaks of tabanid abundance.