Parasites of Fish from the Great Lakes - Great Lakes Fishery ...

Nematodes
Ten species of adult nematodes in seven families were reported from fishes. Many nematode
species are host-specific. Raphidascaris acus was only found in esocids, and Camallanus
oxycephalus, Philometra cylindracea, and Rhabdochona ovifilamenta occurred only in Perca
flavescens. Dichelyne cotylophora was also found in Perca flavescens, but was also reported from
Catostomus commersonii and Ameiuras melas. Cystidicola farionis infected five fish species.
Cystidicola spp. was found only in the swim bladder of salmonids. At least nine nematode species
in seven nematode families have been reported as larval or immature stages. Non-intestinal larvae
of Contracaecum sp., R. acus, D. cotylophora, Cystidicola stigmatura, Eustrongylides tubifex,
Eustrongylides sp., and P. cylindracea were found. Immature Capillaria sp., Spinitectus sp., and
Haplonema hamulatum have been documented in the intestines of Lake Michigan fish.
Acanthocephalans
Eight species of adult acanthocephalans representing four families were reported.
Echinorhynchus salmonis and Acanthocephalus dirus infected 17 and 13 fish species,
respectively. Echinorhynchus salmonis was the most-prevalent and numerous intestinal helminth
parasite of Oncorhynchus. Neoechinorhynchus crassus and Octospinifer macilentus are hostspecific
to catostomids. All species represented as larvae or immature individuals (A. dirus, E.
salmonis, Pomphorhynchus bulbocolli, Leptorhynchoides thecatus) found in non-intestinal sites
are also included in the adult category. Some female E. salmonis found in non-intestinal sites of
Osmerus mordax were gravid.
Leeches
Five species of leeches (Desserobdella picta, Placobdella parasitica, Piscicola milneri, Piscicola
punctata, Piscicolaria sp.) representing two families have been reported. Desserobdella picta and
P. milneri parasitized two and three fish species, respectively.
Crustaceans
At least seven species of copepods in two families were found on Lake Michigan fish. Four
species of Ergasilus occurred on the gills of a variety of species. Ergasilus caeruleus and
Ergasilus luciopercarum were found on four and five fish species, respectively. Achtheres
pimelodi occurred on three fish species, and two species of Salmincola were found on salmonids.
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