Parasites of a marine benthic fish in the Southwester Atlantic: searching for recurrent geographical patterns of community structure

VALES DAMIÁN GUILLERMO; GARCÍA NÉSTOR ANÍBAL; CRESPO ENRIQUE ALBERTO; TIMI, JUAN TOMÁS

MELBOURNE

Congreso; The XIIth International Congress of Parasitology (ICOPA; 2010

THE AUSTRALIAN SOCIETY OF PARASITOLOGIST

Parasite communities of Raneya brasiliensis are described and its parasites used as biologicaltags to discriminate populations in the southern boundary of its distribution. Fish were caught intwo zones of the Argentinean Sea: one sample from the area of San Jorge Gulf (PatagonianRegion) and three samples from off the coast of Buenos Aires (Bonaerense Region). A total of183 specimens of R. brasiliensis were examined for parasites and 11 species were found. Hostbody size and its ecology are pointed out as drivers of the paucity of taxa found. Most parasiteswere unspecific larval stages, with the exception of a cucullanid nematode. Multivariatesimilarity analyses allowed the identification of three stocks: one in the San Jorge Gulf, and twoother one off the coast of Buenos Aires Province. The parasite species that contributed most tothe separation of the samples were generally those identified as biological markers in previousstudies on other fish species. Patterns of distance decay in similarity among communities in R.brasiliensis were found; with dissimilarity values between distant localities (i.e. betweenPatagonian and Bonaerense regions) being higher than between close ones (i.e. localities of theBonaerense region). Whereas the composition and structure of parasite assemblages inBonaerense waters reflect those of other fish species in the areas, being mainly determined by thecomposition of the compound community, no repeatable patterns were found in the compositionof parasites assemblages when R. brasiliensis was compared with other hosts species inPatagonia.