The two bathydraconid species, Gymnodraco acuticeps and Cygnodraco mawsoni, caught in the Ross Sea (Antarctic summer 2002) were examined for internal parasites. All specimens (four G. acuticeps and one C. mawsoni) were infected. G. acuticeps harboured larval Cestoda (bilocular tetraphyllidean cercoids, diphyllobothriid plerocercoids) and Nematoda (Contracaecum spp.), acanthocephalan cystacanths and adult helminths (three species of Digenea and one species of Nematoda). Two specimens of C. mawsoni (including data from one additional specimen examined earlier) were infected by larval Cestoda (bilocular cercoid) and Nematoda (Contracaecum spp.) and adult helminths (three species of Digenea and one species of Nematoda). The present data are compared and discussed with the relevant literature data.
Trematomus newnesi (Nototheniidae), a bentho-pelagic fish, caught off Adélie Land (eastern Antarctic) was examined for the presence of internal parasitic worms. These fishes were infected with 11 species and larval forms of parasites: Digenea (Macvicaria pennelli, Neolebouria terranovaensis, Genolinea bowersi, and Elytrophalloides oatesi), larval Cestoda (two forms of tetraphyllidean metacestodes, bilocular form and trilocular form, and diphyllobothriid plerocercoids), Acanthocephala (Metacanthocephalus campbelli, M. johnstoni) and larval Nematoda (Contracaecum osculatum, C. radiatum). Larval cestodes were the dominant parasites, whereas acanthocephalans were relatively rare. Five species and larval forms were recorded also in fish caught in the Davis Sea. A check list of parasites of T. newnesi recorded in the eastern- and western Antarctic comprises 21 species and larval forms. Probably, T. newnesi plays an important role in life cycles of parasitic worms in the Antarctic.
The infections of four fish species, Trematomus newnesi, T. bernacchii, Lindbergichthys nudifrons and Harpagifer antarcticus with parasitic worms, in the coastal zone off the Vernadsky Station (Argentine Islands, West Antarctica) are described. Data on infections are compared with previous results from Admiralty Bay at the South Shetland Islands. Indices of infection are for each host-parasite relationship. In total, 16 taxa of parasites were recorded: 6 digeneans, 3 larval cestodes, 4 (adult and cystacanth) acanthocephalans, and 3 (adult and larval) nematodes. Fifteen of them have been previously recorded in Notothenia coriiceps from this area. Hence, the number of parasitic taxa recorded in this region increased from 21 to 22. Either the digenean Macvicaria georgiana or acanthocephalan Corynosoma pseudohamanni were dominants in different hosts. Trematomus bernacchii was the most strongly infected, especially with M. georgiana (prevalence 100%, mean abundance 113.7). The infection parameters of the majority of parasites were lower at the Vernadsky Station than in the Admiralty Bay, especially for host-parasite relations with larval cestodes and nematodes. The presently reported study have confirmed that the southern range of distribution of two acanthocephalans, Aspersentis megarhynchus and Corynosoma hamanni extends south to the area near the Argentine Islands.