The Gyrodactylus (Monogenea, Gyrodactylidae) parasite fauna of freshwater sand gobies (Teleostei, Gobioidei) in their centre of endemism, with description of seven new species
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Abstract
While Gobioidei comprises showcases of (adaptive) radiation, the scientific interest they yielded did not ensure full understanding of goby biodiversity. Even in a well-studied region like Europe, wide knowledge gaps remain. Sand gobies represent one of the few clades whose monogenean parasites have been thoroughly studied. However, in the Balkans, part of the sand gobies' centre of endemism, these parasites were unstudied. We focus on Greek and Croatian freshwater gobies. From five sand goby species, the first parasites are reported, describing seven new Gyrodactylus species. Economidichthys pygmaeus harbours Gyrodactylus benedeni sp. n. and Gyrodactylus dorlodoti sp. n. Its congener E. trichonis hosts G. meelkopae sp. n. Knipowitschia milleri was found to host G. charon sp. n., K. thessala is infected by G. bios sp. n., and K. croatica by G. douglasadamsi sp. n. and G. hellemansi sp. n. Gyrodactylus bubyri was found on its type host K. caucasica. A diverse parasite fauna is expected for a region known for its biodiversity and endemism. The contribution of parasites to species richness in such hotspots is overlooked. The observed species richness per host is rather low compared to the better-studied eastern Atlantic sand gobies. Host vicariance is considered to mediate parasite specificity in this fauna. Some new flatworm species display unique morphological features, such as the remarkable size of the marginal hook sickle proper compared to its foot in the Economidichthys parasites, or a characteristically kinked marginal hook sickle in G. douglasadamsi sp. n. These features reflect their hosts' endemism in the Balkans.
Keywords
Type Host Gill Filament Parasite Fauna Male Copulatory Organ Apical SpineNotes
Acknowledgements
We thank D. Mrdak, V. Pešić (University of Montenegro), E. Kalogianni, L. Vardakas, Y. Chatzinikolaou, V. Tachos, D. Kommatas, N. Koutsikos and Y. Kapakos (HCMR) for help with sampling; L. Schoofs, L. Arckens, E. Meelkop, J. Nys, J. Aerts and L. Minerva (KU Leuven) for (help with) the use of a ZEISS microscope; B. Geens for help with collecting part of the Gyrodactylus data; A. Vidalis (Biodiversity East) for providing Fig. 1; and W.A. Boeger (Universidade Federal do Paraná, Brazil), J. Cable (Cardiff University, Wales, United Kingdom), A. Pariselle (Institut de Recherche pour le Développement, France), M. Ondračková (Institute of Vertebrate Biology, Academy of Sciences of the Czech Republic) and I. Přikrylová (Masaryk University, Czech Republic) for useful suggestions on monogenean work. M.P.M.V and T.H. benefited from a PhD and a postdoctoral fellowship, respectively, of the Research Council – Flanders (FWO – Vlaanderen). Fieldwork was partly financed by a travel grant to M.P.M.V. from BeNCoRe (Belgian Network for Coastal Research; ENCORA coordination action contract number FP6-2004-Global-3–518120). M.P.M.V. is currently supported by ECIP - Centre of excellence, GAČR No. GBP505/12/G112.
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