Stomach content analysis was performed to 20 individuals of D. formosum (nine collected at night and 11 during the day); 30 of D. radiale (three collected at night and 27 during the day); 30 of E. marginatus (20 collected during the evening twilight, six during the day, and four at night);
and 30 of M. acutirostris (28 collected during the night and two at the beginning of the evening twilight). The collected specimens were weighted (0.1 g of precision) and fixed in 10% formalin on capture. Voucher specimens are deposited in the fish collection of the Laboratório de Ictiologia de Ribeirão Preto (LIRP), Departamento de Biologia (FFCLRP),Universidade de São Paulo, in Ribeirão Preto, Brazil (D.formosum LIRP 4297-4304; D. radiale LIRP 4305-4315; E. marginatus LIRP 4316-4324 and M. acutirostris LIRP 4325-4332).