Parasite infracommunities of Helicolenus lahillei Norman, 1937 (Scorpaeniformes. Sebastidae) in Southwest Atlantic Ocean

CANTATORE, D.M.P.; TRINGALI, L.S.; TIMI, J.T.

Viña del Mar

Simposio; VIII International Symposium on Fish Parasites; 2011

Universidad de Antofagasta, Chile

Helicolenus lahillei Norman, 1937 (rubio) is a benthopelagic deep-water fish that inhabits the continental shelf edge and upper slope, occurring off Uruguay, north Argentina and south Brazil. A total of 139 specimens of H. lahillei (LT: 17.7 ・} 2.5) obtained from a research cruise (36.0-37.0°S – 53.5-54.5°W) carried out during February, 2008 were examined for parasite in order to describe its parasite infracommunities for the first time. From the total sample, 94.2% fish were parasitized with at least one of the 18 parasite species recorded: 2 monogeneans (Microcotyle sp. and Neodiplectanotrema helicoleni); 1 copepoda (Acanthochondria helicoleni); 1 acanthocephalan (Corynosoma australe); 4 cestodes (Grillotia sp1 and sp2, Hepatoxylon sp. and an undifferentiated larvae); 3 digeneans (Derogenes varicus, Elytrophaloides oatesi and Psettarium sp.); 5 nematodes (Contracecum sp., Anisakis simplex s.l. and Hysterothylacium sp. –all as larvae-, Hysterothylacium aduncum adult and larvae, and Cucullanus incertus adult); and 2 myxozoan (Myxidium sp. and Ceratomyxa sp.). We collected 737 macroparasite individuals (total mean abundance = 5.7 } 4.3); being H. aduncum the most abundant species that dominated 53.4% of infracommunities. The values of infracommunity diversity descriptors were: species richness = 3.0 } 0.9 (2-5); diversity (Brillouin) = 0.5 } 0.2; dominance (Berger-Parker) = 0.6 } 0.2 and evenness = 0.8 } 0.2. Although the species richness was high at component community level, the low values of infracommunity descriptors and especially of abundance, when compared with other small benthic fishes of the region, could reflect the influence of the cold water Malvinas Current.Norman, 1937 (rubio) is a benthopelagic deep-water fish that inhabits the continental shelf edge and upper slope, occurring off Uruguay, north Argentina and south Brazil. A total of 139 specimens of H. lahillei (LT: 17.7 ・} 2.5) obtained from a research cruise (36.0-37.0°S – 53.5-54.5°W) carried out during February, 2008 were examined for parasite in order to describe its parasite infracommunities for the first time. From the total sample, 94.2% fish were parasitized with at least one of the 18 parasite species recorded: 2 monogeneans (Microcotyle sp. and Neodiplectanotrema helicoleni); 1 copepoda (Acanthochondria helicoleni); 1 acanthocephalan (Corynosoma australe); 4 cestodes (Grillotia sp1 and sp2, Hepatoxylon sp. and an undifferentiated larvae); 3 digeneans (Derogenes varicus, Elytrophaloides oatesi and Psettarium sp.); 5 nematodes (Contracecum sp., Anisakis simplex s.l. and Hysterothylacium sp. –all as larvae-, Hysterothylacium aduncum adult and larvae, and Cucullanus incertus adult); and 2 myxozoan (Myxidium sp. and Ceratomyxa sp.). We collected 737 macroparasite individuals (total mean abundance = 5.7 } 4.3); being H. aduncum the most abundant species that dominated 53.4% of infracommunities. The values of infracommunity diversity descriptors were: species richness = 3.0 } 0.9 (2-5); diversity (Brillouin) = 0.5 } 0.2; dominance (Berger-Parker) = 0.6 } 0.2 and evenness = 0.8 } 0.2. Although the species richness was high at component community level, the low values of infracommunity descriptors and especially of abundance, when compared with other small benthic fishes of the region, could reflect the influence of the cold water Malvinas Current.