Incidence and Distribution of Infestation by Sphyrion lumpi (Krøyer) on the Redfish, Sebastes marinus (L.), of the Western North Atlantic
Investigations of infestation of redfish by female Sphyrion lumpi, in the Newfoundland area, showed that in the Labrador area Sphyrion were generally distributed all over the body but with the greatest infestation in the cloacal region. In the eastern Grand Bank area there was a strongly ventral dis...
| Published in: | Journal of the Fisheries Research Board of Canada |
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| Main Authors: | , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Canadian Science Publishing
1960
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| Subjects: | |
| Online Access: | http://dx.doi.org/10.1139/f60-002 http://www.nrcresearchpress.com/doi/pdf/10.1139/f60-002 |
| Summary: | Investigations of infestation of redfish by female Sphyrion lumpi, in the Newfoundland area, showed that in the Labrador area Sphyrion were generally distributed all over the body but with the greatest infestation in the cloacal region. In the eastern Grand Bank area there was a strongly ventral distribution of the parasite on the trunk with over 40% of the parasites in the cloaca. This is contrasted with previously published data from the Gulf of Maine where most of the Sphyrion were situated antero-dorsally, near the base of the spiny first dorsal fin.The major centre of infestation, in the Newfoundland area, of redfish by Sphyrion was off southern Labrador east of Hamilton Inlet Bank with as high as 8% of the redfish infested. Centres of less infestation were found on the southern part of the eastern slope of the Grand Bank and in the southeastern part of the Gulf of St. Lawrence. Sphyrion were very scarce on the southwestern Grand Bank, the western part of the south coast of Newfoundland and in the northern part of the Gulf of St. Lawrence. Sphyrion were not noted on redfish from the NE Grand Bank, Flemish Cap and from the Nova Scotian Shelf. A study of residual remains, in redfish fillets, of the cephalothorax from individuals of previous Sphyrion generations showed the same centres of abundance but with some spreading of the previously infested fish in 2 of 3 areas in the direction of the deep-water current, thus indicating the possibility of very slow migration of some individual redfish with the current.It is believed that almost all the redfish discussed in this paper are of the mentella type. |
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