Helminths of Steindachnerina insculpta in two distinct stretches of the Taquari River, state of Sao Paulo, Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Processo FAPESP: 10/19543-6

The purpose of this study was to evaluate the helminth fauna of Steindachnerina insculpta in the Taquari River, a tributary of the Jurumirim reservoir in the state of Sao Paulo, and to investigate whether some helminth species may act as a bioindicator of environmental impact. The host fish sample was composed of 60 specimens, with 30 individuals sampled in a lotic stretch and 30 in a lentic stretch. The following were found: the monogeneans Anacanthoroides mizelli, Diaphorocleidus kabatai, Urocleidoides sp. and Euryhaliotrema chaoi; the digenean Sphincterodiplostomum musculosum and unidentified metacercariae; the nematode Travnema travnema and unidentified larvae; and the acanthocephalan Gorytocephalus plecostomorum. The total prevalence of monogeneans (z = 3.14; p = 0.002) and A. mizelli (z = 3.879; p = 0.001), as well as the mean abundance of total monogeneans (U = 642.0; p <= 0.001) and A. mizelli (U = 623.5; p = 0.001), were higher in the lentic stretch. Steindachnerina insculpta and its monogeneans comprise a potential group that could be used to investigate environmental impact, as demonstrated in this study.