| Abstract: The acanthocephalan species Quadrigyrus torquatus Van Cleave, 1920 has been found in different hosts from South America, but recent papers have not focused on its morphology traits. Different species of Astyanax Baird & Girard, 1854 were collected with seine nets between January 2017 and October 2017 in Pintada Island, Lake Guaíba, Porto Alegre city (30º17’11’’S and 51º18’01”W), Rio Grande do Sul State, Brazil. Acanthocephalans found in cysts were processed according to the techniques for the group. Specimens of Q. torquatus were identified based mainly in the morphology of proboscis hooks and trunk spines, and by the measurements made using light microscopy. Supplemental observations on the morphology of Q. torquatus were made for the first... |
