Little knowledge of the diseases, parasites and pathogens presented by fish of the genus Epinephelus (Roumbedakis et al., 2013) is available. Parasites serves as keystones for understanding the history of biotas because of their critical value as phylogenetic, ecological and biogeographic indicators of their host groups (Hoberg and Klassen, 2002).

The Goliath grouper, Epinephelus itajara (Lichtenstein, 1822) is the largest species of the Epinephelinea, reaching 400kg and measuring more than 3m in length, found in tropical and subtropical waters of the Atlantic Ocean, inhabiting estuarine and coastal areas (Bullock et al., 1992). Due the decadence of the Goliath grouper population in several regions in Brazil, the Ministry of Fisheries and Aquaculture prohibited until the year 2023 the capture of this species in Brazilian jurisdictional waters (Sanches et al., 2015).

Therefore, the objective of this study was to identify the parasite isopods found in the Goliath grouper and thus contribute to the formation of a database related to the parasitology of the species.

Two specimens of Goliath grouper, a male of total length 1.73m and a female of total length 1.0m were captured during research expedition (SISBIO 15080-2 and 31719-1), using line and hook (non-destructive sampling), in southern Atlantic Ocean, on the coast of Parana (Brazil), between 25[degrees] and 27[degrees] south latitude.

During this sampling and identification fishes were examined, observing the presence of three ectoparasites of the order Isopoda in the pectoral fin and in operculum of the Goliath grouper. After the procedures, the specimens were returned alive to the same capture site.

The isopods were carefully removed with the aid of tweezers and was placed in test tube for preservation in 70% alcohol. To identify the species the ectoparasites were...