1 research outputs found
Weak population structure and expansive demographic history of the monogenean parasite Kapentagyrus spp. infecting clupeid fishes of Lake Tanganyika
No full textLake Tanganyika, East Africa, is the oldest and deepest African Great Lake and harbours one of the most diverse fish assemblages on earth. Two clupeid fishes, Limnothrissa miodon and Stolothrissa tanganicae, constitute a major part of the total fish catch, making them indispensable for local food security. Parasites have been proposed as indicators of stock structure in highly mobile pelagic hosts. We examined the monogeneans Kapentagyrus limnotrissae and Kapentagyrus tanganicanus (Dactylogyridae) infecting these clupeids to explore the parasites' lake-wide population structure and patterns of demographic history. Samples were collected at seven sites distributed across three sub-basins of the lake. Intraspecific morphological variation of the monogeneans (n = 380) was analysed using morphometrics and geomorphometrics of sclerotised structures. Genetic population structure of both parasite species (n = 246) was assessed based on a 415 bp fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Overall, we observed a lack of clear geographical morphological differentiation in both parasites along a north-south axis. This lack of geographical population structure was also reflected by a large proportion of shared haplotypes, and a pattern of seemingly unrestricted gene flow between populations. Significant morphological and genetic differentiation between some populations might reflect temporal differentiation rather than geographical isolation. Overall, the shallow population structure of both species of Kapentagyrus reflects the near-panmictic population structure of both host species as previously reported. Morphological differences related to host species identity of K. tanganicanus were consistent with incipient speciation at the genetic level. Both parasite species experienced a recent demographic expansion, which might be linked to paleohydrological events. Finally, interspecific hybridisation was found in Kapentagyrus, representing the first case in dactylogyrid monogeneans.sponsorship: The authors would like to thank L. Raisingerova, C. Rahmouni, H. Zimmermann, A. P. H. Bose and W. Salzburger for help with collecting host samples. M. Jorissen is gratefully acknowledged for fruitful discussions about monogenean morphological variability and help in the laboratory. Special thanks to the staff of the parasitological group at Masaryk University, Brno (Czech Republic), the Research Group Zoology at Hasselt University (Belgium), Research Centre of Hydrobiology in Uvira (DR Congo) and Fisheries Research Unit in Mpulungu (Zambia) for their hospitality. Research was supported by the Czech Science Foundation (P505/12/G112 (ECIP) and GA19-13573S), EMBRC Belgium - FWO project GOH3817N as well as by a joint program between the Austrian Agency for International Cooperation in Education and Research (OEAD; project number CZ 08/2018; to SK) and the Ministry of Education, Youth and Sports (project number 8J18AT007). MPMV was co-financed by institutional funding of the Finnish Museum of Natural History and the Belgian Directorate-General for Development Cooperation and Humanitarian Aid (CEBioS program). ELRDK was supported by the Belgian Development Cooperation through VLIR-UOS (VLADOC scholarship NDOC2016PR006 to ELRDK and South Initiative project CD2018SIN218A101). Fieldwork was carried out with the approval of the competent local authorities under mission statement 031/MINRST/CRH-U/2016 and the permission of the Fisheries Department of Zambia and under a study permit issued by the government of Zambia (SP 008732). (Czech Science Foundation|P505/12/G112, Czech Science Foundation|GA19-13573S, EMBRC Belgium - FWO project|GOH3817N, Austrian Agency for International Cooperation in Education and Research (OEAD)|CZ 08/2018, Ministry of Education, Youth and Sports|8J18AT007, Finnish Museum of Natural History, Belgian Directorate-General for Development Cooperation and Humanitarian Aid (CEBioS program), Belgian Development Cooperation through VLIR-UOS (VLADOC scholarship)|NDOC2016PR006, Belgian Development Cooperation through VLIR-UOS (South Initiative project)|CD2018SIN218A101)status: Publishe
