Organisms with wide geographical or phenotypic diversity often constitute assemblages of genetically distinct species or lineages. Within parasites, an emergence of host-specific lineages is assumed to create such cryptic variability; however, empirical evaluation of these processes is scarce. Here, we analyse populations of a parasite with a complex life cycle, wide host spectrum and global distribution, with the aim to reveal factors underlying the evolution of host- or geography-dependent lineages. Using 15 microsatellite loci, deep genetic distances were observed between populations from distant geographical areas. On the local scale, host-mediated genetic structure was found among sympatric samples. Two lineages differing in the spectrum of infected hosts co-occurred in the Euro-Mediterranean area, and two distinct lineages were recovered from Lake Tana in Ethiopia. Although sampled across several host taxa and multiple localities, a lack of marked genetic structure was seen in the populations belonging to one of the European lineages. Only weak genetic differentiation between sympatric samples from two host species was found. Complexity of the parasite life-cycle contributed to such a stratified pattern. Differences in the immune response between fish hosts were suggested as the factor diversifying the populations locally; conversely, high mobility of the parasite due to migration with its bird (definitive) host were assessed to homogenize populations across the area of distribution. However, despite the high mobility, large bodies of salt water prevent the parasite from long-distance migrations, as was demonstrated in an example of the Mediterranean Sea which represented an effective barrier to gene flow.

University of South Bohemia and Institute of Parasitology Biology Centre AS CR Ceské Budejovice Czech Republic

Citace poskytuje Crossref.org

Highly resolved genome assembly and comparative transcriptome profiling reveal genes related to developmental stages of tapeworm Ligula intestinalis

Different hosts in different lakes: prevalence and population genetic structure of plerocercoids of Ligula intestinalis (Cestoda) in Czech water bodies

Unique genetic structure of the human tapeworm Dibothriocephalus latus from the Alpine lakes region - a successful adaptation?

De novo developed microsatellite markers in gill parasites of the genus Dactylogyrus (Monogenea): Revealing the phylogeographic pattern of population structure in the generalist parasite Dactylogyrus vistulae

Host specificity driving genetic structure and diversity in ectoparasite populations: Coevolutionary patterns in Apodemus mice and their lice

Ultrastructural study of vitellogenesis of Ligula intestinalis (Diphyllobothriidea) reveals the presence of cytoplasmic-like cell death in cestodes

Genetic interrelationships of North American populations of giant liver fluke Fascioloides magna