Gut contents of 304 individuals of the silverside Odontesthes humensis de Buen, 1953 were analyzed using frequency of occurrence (FO%) and gravimetric (P%) methods. A total of 207 individuals (68.1%) had some food itens in the gut, while 97 individuals (31.9%) had empty guts. The silverside Odontesthes humensis has presented a benthic carnivorous diet, preying mainly on molluscs and arthropods. The molluscs Heleobia sp. (FO = 61.35%) and Corbicula fluminea (Müller, 1774) (FO = 57.97%) were the most frequent itens, followed by Neocorbicula limosa (Maton, 1811) (FO = 17.39%). Among the arthropods, the coleoptera insects (FO= 18.84%) were dominant followed by, insect larvae (FO = 6.76%), the crustacean Palaemonetes argentinus Nobili, 1901 (FO = 1.93%) and... |