HELMINTHIC ENDOFAUNA OF FOUR SPECIES OF FISH FROM LOWER JARI RIVER, A TRIBUTARY OF THE AMAZON BASIN IN BRAZIL

Abstract

Studies on parasites of wild fish populations are important for knowledge of biodiversity, since parasites represent a great fraction of the planet's biodiversity. The present study investigated the helminths fauna of Leporinus friderici, Mylossoma duriventre, Hoplerythrinus unitaeniatus and Osteoglossum bicirrhosum collected from the lower Jari River, in the state of Amapá in the eastern Amazon region, Brazil. These fish, which have varying eating habits, were caught using gill nets with different mesh sizes for analysis of helminths, using standard methodologies. The helminths collected from these hosts were: Procamallanus (Spirocamallnus) inopinatus, Guyanema seriei seriei, Contracaecum sp., Eustrongylides sp. (Nematoda), Clinostomum marginatum, Dadaytrema oxycephala, Caballerotrema aruanense, Posthodiplostomum sp. (Digenea), Quadrigyrus nickoli and Neoechinorhynchus sp. (Acanthocephala). Hoplerythrinus unitaeniatus presented the highest prevalence, intensity and mean abundance of C. marginatum, while M. duriventre was the host with lowest level of this parasite. The greatest diversity was of Contracaecum sp., sole helminth found in all species of fish studied. The presence of larvae of endoparasites indicates that these fish are intermediate hosts in the Jari River basin.