Biology subjects

Keve, G.

Publications and source records attributed to Keve, G..

4 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↗