Biology subjects

Hornok, S.

Publications and source records attributed to Hornok, S..

6 recordsLinked to original sources

bioRxiv2025

First occurrence of parasitic isopod (Braga nasuta, Schioedte & Meinert, 1881) on ornamental fish in Europe

Parasitic crustaceans represent a significant threat to both freshwater and marine aquaculture, with several families capable of inducing severe diseases with high mortality rates and therefore significant economic losses. Among them, isopods of the genus Braga (Cymothoidae) are haematophagous parasites of neotropical fish, causing anaemia, tissue damage, and mortality. Braga nasuta, endemic to Brazil, has been reported from various hosts, including ornamental species exported worldwide. During routine examination of imported cardinal tetra (Paracheirodon axelrodi, Schultz, 1956), the authors detected that one of the fish harbored an adult male isopod ([~]6.21 mm long, 2.66 mm wide) attached anterior to the dorsal fin. Based on morphological identification, the parasite was identified as Braga nasuta. No secondary pathogens were observed in affected fish. Given the global trade in ornamental species, the introduction of B. nasuta into non-native regions underscores the importance of quarantine and parasite monitoring. While the potential ability of this parasite to establish populations in Europe requires further studies, vigilance is warranted to prevent potential spread and ecological impact. In this study, the authors document the first occurrence of B. nasuta in Europe, detected on a cardinal tetra (P. axelrodi) imported to a Hungarian public aquarium.

zoology↗

bioRxiv2025

Reports of Lipoptena fortisetosa on dogs and in the environment, and evidence of its widespread establishment in Hungary

Lipoptena fortisetosa is a louse fly of East Asian origin that is considered a potential vector of several pathogenic bacteria and is most commonly associated with deer (Cervidae). The species has been detected in multiple countries in Europe; however, its exact distribution range is unknown. A single individual was detected on a dog at a veterinary clinic in Budapest, Hungary, a country where the presence of L. fortisetosa has not yet been confirmed. After acquiring information regarding the recent whereabouts of the dog, targeted louse fly collection with insect nets was performed in a forest in Central Transdanubia. Of the 30 flying, unfed specimens of Lipoptena spp., 23 were morphologically identified as L. fortisetosa. Following this, louse fly collections have been conducted across Hungary during the fall of 2025. According to these results, L. fortisetosa can be considered widespread in the country, and that this parasite can be effectively transported by dogs. The findings draw attention to the potential medical and veterinary significance of the emergence of novel vectors that may have been introduced through animal transport.

zoology↗

bioRxiv2025

First record of Argulus japonicus infestation onCyprinus carpio in Hungary, and the first descriptionof Argulus japonicus subsp. europaeus subsp. nov.Keve, 2025

Species belonging to the genus Argulus are globally distributed fish parasites. Their veterinary significance primarily lies in their disruptive presence and their role as mechanical vectors. Although Argulus japonicus Thiele, 1900 is a widely distributed representative of this genus that feeds on freshwater fish, only Argulus foliaceus (Linnaeus, 1758) had previously been reported in Hungary. The aim of this study was to investigate the fish louse fauna in a local common carp (Cyprinus carpio Linnaeus, 1758) population. To the best of our knowledge, this is the first study to report the occurrence of A. japonicus in Hungary. Our detailed molecular analyses, including the complete mitochondrial genome, revealed for the first time that the A. japonicus specimens found in Hungary differ significantly from their Far Eastern counterparts. Furthermore, cytochrome c oxidase subunit I (cox1) sequence analysis -- a region known to be stable within the species -- showed that while our sequences were nearly identical to those of other European specimens, they differed markedly from the available Asian isolates. The phylogenetic analysis also confirmed this divergence. The European A. japonicus sequences form a clearly distinct sister group to the Asian lineages. In light of these findings, and based on thorough morphological examinations, the authors propose that the specimens found in Hungary represent a new subspecies, Argulus japonicus subsp. europaeus subsp. nov. Keve, 2025.

zoology↗

bioRxiv2023

Ornithological and molecular evidence of a reproducing Hyalomma rufipes population under continental climate in Europe

BackgroundReports on adult Hyalomma ticks in certain regions of the Carpathian Basin date back to the 19th century. These ticks were thought to emerge from nymphs dropping from birds, then molting to adults. Although the role of migratory birds in carrying ticks of this genus is known from all parts of Europe, in most countries no contemporaneous multiregional surveillance of bird-associated ticks was reported which could allow the recognition of hotspots in this context. MethodsIxodid ticks were collected from birds at seven ringing stations in Hungary, including both the spring and autumn migration period in 2022. Ixodes and Haemaphysalis species were identified morphologically, whereas Hyalomma species molecularly. ResultsFrom 38 passeriform bird species 957 ixodid ticks were collected. The majority of developmental stages were nymphs (n=588), but 353 larvae and 16 females were also present. On most birds (n=381) only a single tick was found and the maximum number of ticks removed from the same bird was 30. Tick species were identified as Ixodes ricinus (n=598), Ixodes frontalis (n=18), Ixodes lividus (n=6), Haemaphysalis concinna (n=322), and D. reticulatus (n=1). All twelve Hyalomma sp. ticks (11 engorged nymphs and an unengorged larva) were identified as Hyalomma rufipes based on three mitochondrial markers. This species was only found in the Transdanubian region and along its southeastern border. The Common Blackbird (Turdus merula) and the European Robin (Erithacus rubecula) were the two main hosts of I. ricinus and I. frontalis, whereas H. concinna was almost exclusively collected form long-distance migrants. The predominant hosts of H. rufipes were reed-associated bird species, the Sedge Warbler (Acrocephalus schoenobaenus) and the Bearded Reedling (Panurus biarmicus), both harboring these ticks at the end of June (i.e., the nesting period) in southwestern Hungary. ConclusionsThis study provides ornithological explanation for the regional, century-long presence of adult Hyalomma ticks under continental climate in the Transdanubian Region of the Carpathian Basin. More importantly, the autochthonous occurrence of a H. rufipes population was revealed for the first time in Europe, based on the following observations: (1) the bird species infested with H. rufipes are not known to migrate during their nesting period; (2) one larva was not yet engorged; (3) the larva and the nymphs must have belonged to different local generations; and (4) all H. rufipes found in the relevant location were identical in their haplotypes based on three maternally inherited mitochondrial markers, probably reflecting founder effect. This study also demonstrated that the species of ticks carried by birds were significantly different between collection sites even within a geographically short distance (200 km). Therefore, within a country multiregional monitoring is inevitable to assess the overall epidemiological significance of migratory birds in importing exotic ticks, and also in maintaining newly established tick species.

zoology↗

bioRxiv2021

Ecdysteroids as natural doping substances in the blood of insectivorous bats

Bats have deserved much scientific attention due to their biological-ecological properties and increasingly recognized epidemiological significance. Ecdysteroids are insect-molting hormones that (under experimental conditions) have stimulating and anabolic effects in mammals, including humans. Therefore, these biologically active compounds are currently under consideration by the World Anti-Doping Agency (WADA) to become doping-controlled substances. Previously we demonstrated that low to high concentrations of ecdysteroids appear in the blood of insectivorous passerine birds. Since passerine birds and echolocating bats share several adaptive mechanisms in connection with flying, and insectivorism is also among their common traits, we hypothesized that ecdysteroids might also be present in the blood of insectivorous bats. To test this hypothesis, blood samples of eight insectivorous bat species were collected and analyzed for the presence of ecdysteroids with highly sensitive targeted ultra-high-performance liquid chromatography coupled to high-resolution quadrupole-orbitrap mass spectrometry method (UHPLC-HRMS). The results supported our hypothesis, because nine ecdysteroids were detected in bat blood. The spectrum of these ecdysteroids was similar in those bat species which have their most preferred food items from the same insect order, supporting insects as the most likely source of these hormones. It was also shown that the spectrum of blood-borne ecdysteroids was broader in the autumn than in the summer, and higher concentrations of 20-hydroxyecdysone were measured in samples of large size bat species in comparison with small size ones. Based on the known physiologic effects of ecdysteroids, we postulate that these results might have implications on the metabolic rate and parasite burdens of insectivorous bats.

zoology↗

bioRxiv2020

The heart microbiome of insectivorous bats from Central and South Eastern Europe

Host associated microbiome not only may affect the individual health-status or provide insights into the species- or group specific bacterial communities but may act as early warning signs in the assessment of zoonotic reservoirs, offering clues to predict, prevent and control possible episodes of emerging zoonoses. Bats may be carriers and reservoirs of multiple pathogens such as viruses, bacteria and parasites, showing in the same time robust immunity against many of them. The microbiota plays a fundamental role on the induction, training and function of the host immune system and the immune system has largely evolved in order to maintain the symbiotic relationship of the host with these diverse microbes. Thus, expanding our knowledge on bat-associated microbiome it can be usefully in understanding bats outstanding immune capacities. The aim of this study was to investigate the presence of different bacterial communities in heart tissue of insectivorous bats, Nyctalus noctula, Pipistrellus pipistrellus and Rhinoplophus hipposideros, from Central and Eastern Europe using high-throughput sequencing of variable regions of the 16S rRNA. In addition, species-specific PCRs were used to validate the presence of the vector-borne pathogens Bartonella spp. and Rickettsia spp. In this study we identified a wide variety of bacterial groups, with the most abundant phyla being Proteobacteria and Firmicutes. The results showed that at individual level, the year or location had no effect on the diversity and composition of the microbiome, however host species determined both structure and abundance of the bacterial community. We report the presence of vector-borne bacteria Bartonella spp. in samples of N. noctula and indications of Rickettsia spp. in R. hipposideros. Our results provide a first insight into the bacterial community found in heart tissue of bats from Central and South Eastern Europe.

microbiology↗