Host specificity and distribution of the swim-bladder nematodes, Cystidicola farionis Fischer, 1798 and C. cristivomeri White, 1941 (Habronematoidea), in salmonid fishes of Ontario

• Published in: Canadian Journal of Zoology
• Main Authors: Lankester, Murray W., Smith, John D.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1980
• Subjects: Oncorhynchus gorbuscha
• Online Access: http://dx.doi.org/10.1139/z80-181; http://www.nrcresearchpress.com/doi/pdf/10.1139/z80-181

Cystidicola farionis is reported in Coregonus clupeaformis, C. artedii, C. hoyi, C. nigripinnus (new host record), Prosopium cylindraceum, Oncorhynchus gorbuscha (new North American record), O. kisutch, O. tshawytscha (new host record), Salmo gairdneri, S. trutta, Salvelinus fontinalis, S. namaycush, S. namaycush × S. fontinalis, and Osmerus mordax. The last five fishes listed, however, are considered unsuitable hosts for C. farionis as few, if any, worms reached sexual maturity in these hosts. Coregonus clupeaformis is also unsuitable as a host for C. farionis in lakes Superior and Nipigon. The swim-bladder nematode that matures in lake whitefish in Lake Huron and some inland lakes in northwestern Ontario may be a new species.Factors that may affect the abundance of C. farionis in various fishes are examined and the relative importance of different amphipods as sources of infection is discussed.Cystidicola cristivomeri matures only in hosts of the genus Salvelinus, including S. namaycush and S. alpinus, and is reported here for the first time in S. fontinalis.Ulcerations in the wall of the swim-bladder were seen only in S. gairdneri infected with C. farionis and in S. namaycush infected with C. cristivomeri. The lesions apparently resulted when unusually large numbers of swim-bladder nematodes were present.