Angiostrongylus cantonensis is an invasive zoonotic nematode which causes eosinophilic meningitis in accidental hosts – vertebrates including humans – and is known to impact wildlife. Even though the parasite originates in Southeast Asia, it has spread worldwide, especially into fragile island ecosystems. The Canary Islands are a biodiversity hot spot with numerous endemic species affected by biological invasions. Among others, Rattus rattus and Rattus norvegicus threaten many endemic species by predation and may spread invasive pathogens, such as the rat lungworm A. cantonensis, which was first described in Tenerife in 2010. Since it is known that lizards can act as paratenic hosts for A. cantonensis and Gallotia galloti is a lizard abundant in Tenerife, the aim of this study was to reveal the role of these endemic lizards in the parasite's life cycle. Gallotia galloti were captured in Tegueste, Tenerife, and after euthanasia, liver and tail muscle samples were examined for the presence of A. cantonensis. During microscopic examination, 8/36 liver samples (22.2%) contained granulomas with nematode larvae. In total, 10/39 liver samples (25.6%) and 7/36 tail muscle samples (19.4%) were positive for A. cantonensis DNA using qPCR. This is a first report of a reptile endemic to the Canary Islands acting as paratenic host of A. cantonensis. The fact that the parasite is obviously well-established in the island ecosystem and exploits endemic lizards as hosts may have important implications for the parasite's ecoepidemiology. Moreover, the parasite might threaten other species which depend on lizards in the island trophic web.

Background Endemic lizards of the genus Gallotia are of high ecological value to the terrestrial ecosystem of the archipelago of the Canary Islands, being potent seed spreaders as well as an important component of the diet of other vertebrates. The endemic lizard Gallotiagalloti in Tenerife has recently been reported to be a paratenic host of Angiostrongyluscantonensis, an invasive metastrongylid with zoonotic potential that is associated with rats as definitive hosts. However, microscopic examination of G.galloti tissue samples also revealed the presence of other metastrongylid larvae inside granulomas on the liver of this reptile. The aim of this study was to investigate the presence of helminths other than A.cantonensis in tissues of G.galloti from Tenerife. Methods A multiplex-nested PCR targeting the internal transcribed spacer 1 was designed that enabled the species-specific detection of A.cantonensis, Angiostrongylusvasorum, Aelurostrongylusabstrusus, Crenosomastriatum and Crenosomavulpis. Liver samples from 39 G.galloti were analysed. Results Five metastrongylids were detected: A.cantonensis (15.4% of samples analysed), A.vasorum (5.1%), Ae.abstrusus (30.8%), C.striatum (30.8%) and undetermined metastrongylid sequences (12.8%). Co-infection was highly prevalent among the lizards which tested positive. Conclusions The study provides a new specific tool for the simultaneous detection of a range of metastrongylids of veterinary importance as well as new data on the circulation of metastrongylids in an ecosystem dominated by lizards. Graphical Abstract

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In Europe, paramphistomosis caused by Paramphistomum spp. was historically regarded as being of minor importance. However, Calicophoron daubneyi has recently been recognized as an emerging pathogen in Europe due to its increasing prevalence and negative impact on livestock production. In search for paramphistomid flukes, 5573 beef cattle fecal samples from 115 farms across the whole Czech Republic were examined from March 2019 to June 2021. The eggs of paramphistomid flukes were identified in 29.9% of samples. Internal transcribed spacer 2 sequences from 90 adult flukes and 125 fecal samples collected across Czech Republic confirmed C. daubneyi infection in the Czech beef cattle. Ninety mitochondrial DNA sequences obtained from adult C. daubneyi specimens revealed 13 individual haplotypes, two of them recorded for the first time. Although C. daubneyi is a new parasite in beef cattle herds in the Czechia, it clearly dominates the parasitological findings in the country's beef cattle. The common occurrence of C. daubneyi in most of the beef cattle herds indicates environmental conditions suitable also for the life cycle of Fasciola hepatica and risk of its emergence.