Aspectos ecológicos dos ectoparasitos branquiais de <em>Satanoperca pappaterra</em> (Heckel, 1840) (Cichlidae) da planície de inundação do alto rio Paraná, Brasil

Abstract

The gills of 34 specimens of Satanoperca pappaterra (Heckel, 1840) were analyzed, all of which had been collected from the upper Paran・river floodplain in Brazil, between March 2004 to June 2005. Five species of parasites were found: two digenean (metacercariae), only one monogenean, one cestode (plerocercoid) and one copepod. The monogenean Sciadicleithrum sp. was the most abundant and prevalent, followed by the metacercariae Ascocotyle sp. The results did not show any significant difference in relation to host sex with regard to the prevalence and abundance of parasites between males and females. Only Sciadicleithrum sp. presented a significant positive correlation between standard host length and the abundance and prevalence of parasitism. The metacercariae Ascocotyle sp. presented a significant positive relation only between standard host length and abundance. Through the results, a great abundance was observed for Sciadicleithrum sp. and the metacercariae Ascocotyle sp. in connected lagoons. These differences suggest this type of environment can favor parasitism, especially in the case of monoxenic cycle ectoparasites, such as the monogenean. According to the importance value, only the Sciadicleithrum sp. and the metacercariae Ascocotyle sp. were considered secondary, while the others were considered satellites. The typical pattern of overdispersion or aggregation from the parasite system was observed for Sciadicleithrum sp., the metacercariae Ascocotyle sp. and the metacercariae Diplostomum sp.