OCCURRENCE OF PSEUDOTERRANOVA-DECIPIENS (NEMATODA) IN FISH FROM THE SOUTHEASTERN WEDDELL SEA (ANTARCTIC)

Eleven fish species from the Weddell Sea (Antarctic) were examined for infestation with anisakid nematodes. Two species of the genus Contrac aecum and the sealworm Pseudoterranova decipiens were isolated from th e liver and the body cavity of fish affected. Only two specimens of P. decipiens (1.4%) partly invaded the belly flaps. The following fish s pecies were infested by P. decipiens at the given prevalences: Cygnodr aco mawsoni (74.4%), Trevnatomus scotti (23.2%), Pagetopsis maculatus (10.0%), Cryodraco antarcticus (7.1%), Trematomus lepidorhinus (3.0%), and Dolloidraco longedorsalis (2.7%). All of these, except Trematomus scotti, are new host records. Chaenodraco wilsoni, Chionodraco myersi , Gerlachea australis, Racovitzia glacialis and T. eulepidotus were no t infested. The reasons for low prevalence and intensity of infestatio n are seen in the difficulties of P. decipiens in completing its benth ic life cycle in the Weddell Sea environment, in the absence of shallo w coastal waters due to the floating shelf-ice. Cygnodraco mawsoni is a crucial intermediate host, without which completion of the parasite life cycle might not be possible. In order to clarify the taxonomical position of Antarctic Pseudoterranova, morphological comparisons with specimens of P. decipiens from the German and Norwegian coast were mad e using scanning electron microscopy. Results revealed no differences; hence, all specimens studied belong to the same species P. decipiens.