The herbicide trifluralin is one of the most widely herbicides used in weed control. This study aims to evaluate the genotoxic potential of the trifluralin herbicide on the Colossoma macropomum (tambaqui) using a multi-biomarker approach. The C. macropomum is highly adapted and predominant species in a variety of water bodies in the delta region of the São Francisco River and other river systems in Brazil. The mutagenic and the genotoxic effects of different trifluralin concentrations (0.25, 0.5, 0.75, 1.0 mg L-1) in peripheral erythrocytes of C. macropomum were investigated using micronucleus (MN), comet assay and apoptosis test. After an exposure period of 96 h, the results showed a significant rate of micronuclei and nuclear abnormalities in erythrocytes of C. macropomum exposed to 0.5, 0.75, 1.0 mg L-1 of trifluralin. Compared to controls, the genetic damage index (GDI) showed significant variations (**p < 0.01 and ***p < 0.001) for all the trifluralin concentrations tested. The genotoxicity of trifluralin herbicide on C. macropomum was confirmed by the micronucleus test and comet assay.

This note presents the first documented record of Least Nighthawk, Chordeiles pusillus (Gould, 1861), in S&atilde;o Paulo state, Brazil. The species was observed on four occasions (January 31, April 25, and July 27, 2016; April 27, 2017) in a sandy-rocky habitat on the left bank of Grande river, Mira Estrela municipality. This record is at least 300 km from the previously known occurrences of the species.