Comunidades parasitárias de quatro espécies de peixes anostomídeos do Reservatório de Três Marias, Alto Rio São Francisco, Minas Gerais

Abstract

Two hundred and sixty-six foraging fishes being 69 specimens of Leporinus obtusidens (Valenciennes, 1837), 66 of Leporinus piau Fowler, 1941, 62 of Leporinus reinhardti Lütken, 1875 and 69 of Schizodon knerii (Steindachner, 1875) (Actinopterygii, Anostomidae) were collected in the Três Marias reservoir, upper São Francisco river, along the influence of Borrachudo River (18°12'59"S and 45°17'34"W), during periods of dry, July 2007, 2008 e 2009, and rain, January 2008, 2009 e 2010. Were found 28 species of metazoan parasites: adult specimens of Jainus sp., Rhinoxenus arietinus, Rhinoxenus nyttus, Tereancistrum sp., Urocleidoides sp., unidentified species of Dactylogyridae, Prosthenhystera obesa, Goezia brasiliensis, Paracapillaria piscicola, Procamallanus amarali, Procamallanus sp.1, Procamallanus sp.2, Neoechinorhynchus sp., Argulus multicolor, Ergasilus sp. and Gamispatulus schizodontis; one young specimen of Braga fluviatilis; larval specimens of Henneguya sp., Acanthostomum sp., Austrodiplostomum sp., Metacestóides, Contracaecum sp. Tipo 2, Cystidicoloides sp., Procamallanus sp.3, Rhabdochona acuminata and Spiroxys sp.; beyond adults and larval of Procamallanus inopinatus and Pracamallanus saofranciscencis. Nine species were common in the four hosts: Acanthostomum sp., Ergasilus sp., G. schizodontis, R. arietinus and R. nyttus, Metacestóides, P. piscicola, P. inopinatus and Procamallanus sp1. The species more prevalent, in four species of anostomid hosts, were P. inopinatus and metacestóides. The parasite infracommunities had higher qualitative similarity in the hosts L. obtusidens and L. piau and higher quantitative similarity in S. knerii and L. piau. The structure of parasite communities of L. obtusidens, L. piau, L. reinhardti and S. knerii were similar, due of few core species, limited number of secondary species and the presence of numerous satellite species, low number of significant interspecific associations, beyond the absence of dominance. The species found in the anostomids, except for Ergasilus sp., Contracaecum sp. and P. inopinatus, expanded the list of known hosts in the São Francisco river basin while R. arietinus, R. nyttus, Urocleidoides sp., unidentified species of Dactylogyridae, G. brasiliensis, P. amarali, Procamallanus sp.1, Procamallanus sp.2, Procamallanus sp.3 and G. schizodontis had expanded its geographical distribution for this basin.