Fish were caught by local fishermen in the coast of the State of Rio de Janeiro (21-23°S, 42-45°W), Brazil. Hosts were mostly fresh, but some specimens were kept frozen at –20°C, until examination.

These 201 species comprise 3 Flagellata, 3 Myxozoa, 50 Monogenea, 43 Digenea, 40 Cestoda, 41 Nematoda, 8 Acanthocephala ... gills. Gussevia sp. - Astronotus crassipinnis (Heckel, 1840), gills.