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

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

Viña del Mar

Simposio; VIII Internacional Symposium of Fish Parasites (ISFP); 2011

Helicolenus lahillei Norman, 1937 (rubio) is a benthopelagic deep-water fish that inhabitsthe continental shelf edge and upper slope, occurring off Uruguay, north Argentina andsouth Brazil. A total of 139 specimens of H. lahillei (LT: 17.7 ± 2.5) obtained from aresearch cruise (36.0-37.0°S – 53.5-54.5°W) carried out during February, 2008 wereexamined 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 parasitespecies recorded: 2 monogeneans (Microcotyle sp. and Neodiplectanotrema helicoleni); 1copepoda (Acanthochondria helicoleni); 1 acanthocephalan (Corynosoma australe); 4 cestodes (Grillotia sp1 and sp2, Hepatoxylon sp. and an undifferentiated larvae); 3digeneans (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 2myxozoan (Myxidium sp. and Ceratomyxa sp.). We collected 737 macroparasite individuals(total mean abundance = 5.7 ± 4.3); being H. aduncum the most abundant species thatdominated 53.4% of infracommunities. The values of infracommunity diversity descriptorswere: 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 washigh at component community level, the low values of infracommunity descriptors andespecially of abundance, when compared with other small benthic fishes of the region,could reflect the influence of the cold water Malvinas Current.