Ergasilus sp. (Copepoda: Ergasilidae), parasito de Genidens barbus (Lacepède, 1803) provenientes do Canal de Bertioga, São Paulo

Abstract

ABSTRACT Species of Ergasilus Nordman, 1832 are copepod parasites found worldwide in aquatic environments, and are considered to be major causes of disease in fish farming. One of its important hosts, Genidens barbus, occurs on the east coast of Brazil, in coastal waters, estuaries and the lower reaches of rivers, from Rio de Janeiro to Rio de la Plata, and is considered the most abundant sea catfish in the South and southeast of Brazil. The presence of unknown parasite species is still very large, so there is a need to know more about respect for existing parasitic biodiversity to help species that base new descriptions and even re-descriptions. Thus, the present study aimed to study the biodiversity of G. barbus ectoparasites collected in the Bertioga Channel - SP. We collected seven examples of this hosted by a local fisherman and brought to the Ichthyoparasitology laboratory in the city of Bauru, where they were necropsied. At necropsy, the gills were analyzed for ectoparasites. This organ was passed through the 75µm aperture screen and rinsed in running water and the contents were analyzed under the stereomicroscope for parasites. A total of 111 specimens of crowns parasitizing as gills were found, 40 specimens belonging to the species Ergasilus sp. (Copepoda: Ergasilidae) and the other 71 examples have not yet been identified. The species analyzed in the present study presented average intensity = 13.3 ± 2.44; average abundance = 5.71 ± 0.82 and prevalence = 42.9%. Thus, the study on parasitic biodiversity has presented as an important resource for a more specific knowledge of fish parasites not yet analyzed, as is the case of several species shown in the Bertioga Channel, one of the main Brazilian stages.

KEYWORDS: Ergasilus, Biodiversity, Bertioga Chnanel.