Sarcocystis sp. infection (Apicomplexa: Sarcocystidae) in invasive California kingsnake Lampropeltis californiae (Serpentes: Colubridae) in Gran Canaria.

Invasive species pose a threat not only to biodiversity because they displace or compete with native fauna, but also because of the pathogens they can host. The Canary Islands are an Atlantic biodiversity hotspot threatened by increasing numbers of invasive species, including the California kingsnake Lampropeltis californiae, which was recently introduced to Gran Canaria. Seventy-seven snakes were examined for gastrointestinal parasites in 2019­2020. Sporocysts of Sarcocystis sp. were detected in 10 of them; detection of gamogonia stages in histological sections of 3 snakes confirmed the snake as a definitive host. Partial ssrDNA was amplified using SarcoFext/SarcoRext primers; an additional sequence of Sarcocystis was obtained from the tail muscle of the endemic Gran Canaria giant lizard Gallotia stehlini for a comparison. Identical ssrDNA sequences of unknown Sarcocystis sp. were obtained from 5 different snakes. Phylogenetic analysis showed that Sarcocystis sp. isolated from invasive California kingsnakes is unrelated to Sarcocystis provisionally considered S. stehlini from the endemic lizard. The dixenous coccidia are rarely reported to invade new predator­prey systems. However, the present data suggest that previously unknown Sarcocystis sp. is circulating among invasive snakes and as yet unknown vertebrate intermediate hosts, with undetermined consequences for the Gran Canaria ecosystem.

The winner takes it all: dominance of Calicophoron daubneyi (Digenea: Paramphistomidae) among flukes in Central European beef cattle.

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.