Primeiro registro de pentastomídeo Sebekia sp. em Trichomycterus stawiarski (Siluriformes; Trichomycteridae) no Rio Jirau Alto em Dois vizinhos, Paraná

Abstract

Siluriformes are fish that usually inhabit the bottom of the rivers, remaining between rocks and vegetation. Catfish of the genus Trichomycterus occur in the main hydrographic basins of South America. In the basin of the Iguaçu River, there are 10 described species. The fish may harbor both adult worms and larvae, such as digeneas, cestodes, nematoda, acanthocephals and pentastomids, which may be both definitive and intermediate hosts. In this way, this work has the objective of identifying the composition of the endoparasitary fauna of Trychomycterus stawiarski collected in the Jirau Alto River, located in the municipality of Dois Vizinhos, Paraná. The samples were collected in a period of one year, between April 2018 and April 2019. The samples were collected at four sampling points in the deepest areas near the vegetation for one week, with a daily survey in the period in the morning. The organisms collected were identified at the species level and biometrics (weight, total length and standard) were also performed. The screening of the material in search of the parasites was carried out in the Ecology laboratory of the Universidade Tecnológica Federal do Paraná with the aid of stereomicroscopes, tweezers, Petri dishes and water. The parasites were analyzed and slides were assembled in the Ichthyoparasitology laboratory of the Nucleus of Limnology, Ichthyology and Aquaculture (Nupélia), Universidade Estadual de Maringá (UEM). A total of 24 fish were collected, where 23 were parasitized, parasitic fauna composed of a single phylum Pentastomida, which was identified as Sebekia sp. the parasite was found to be encapsulated nymph around the swimming bladder, intestine, liver or fixed in the musculature, a total of 455 parasites of this species were collected, the identification of the parasite was performed with the help of experts in the field, and with the help of literature. The endoparasite of the phylum pentastomide is not considered a parasite of fish, but of reptiles, in fish this parasite occurs in its phase of nymph or larva. Although there are studies on pentastomides, little is known about their association as a fish parasite, most of the published studies are related to their definitive hosts and their taxonomy, so it is necessary to expand research that allows the knowledge of these parasites.