The infection of black rockcod, Notothenia coriiceps, with digeneans in Admiralty Bay (South Shetland Islands ) within three months, from November 2007 to January 2008, is compared with the infection in the same three months in 1978/79, based on the examination of twenty fish collected in each month. Digenea found in 1978/1979 season were more numerous, and more diverse. Only five digenean species, Macvicaria georgiana , Neolebouria antarctica , Lepidapedon garrardi , Genolinea bowersi and Lecithaster macrocotyle , were recorded during both investigations, whereas three species, Neolepidapedon trematomi , Elytro− phalloides oatesi and Gonocerca phycidis , only in 1978/79. M. georgiana was the dominant species in 1978/79 and sub−dominant in 2007/08. Other digeneans were found in N. coriiceps in 2007/08 invariably together with M. georgiana. G. bowersi was the sub−dominant species in 1978/79 and the most common species in 2007/2008. Infections with Digenea belonging to other species were much less intense. Of the three rare or common species in 1978/79, the two, L. garrardi and L. macrocotyle , occurred in both seasons, whereas E. oatesi occurred only in 1978/79. Three remaining species were sporadic or absent. The overall results therefore demonstrated that infections with almost all digenean species were less strong in 2007/08 than three decades earlier, in 1978/79. Only data on M. georgiana , G. bowersi and L. g arrardi were statistically significant (p <0.05). Data on the occurrence of 14 species of Digenea in N. coriiceps from South Shetland Islands, South Orkney Islands, South Georgia, Argentine Is − lands, Melchior Islands, Adelie Land and Heard Island are given.
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