Bioacoustics supports genus identification in piranhas

In different teleost species, sound production can utilize specific coding schemes to avoid confusion between species during communication. Piranhas are vocal Neotropical fishes, and both Pygocentrus and Serrasalmus produce similar pulsed sounds using the same sound-producing mechanism. In this study, we analysed the sounds of three Pygocentrus and nine Serrasalmus species to determine whether sounds can be used to discriminate piranha species at both the species and genus levels. Our analysis of temporal and frequency data supports the idea that the sounds of Serrasalmus and Pygocentrus species are species specific, and that different acoustic features can be used to differentiate taxa at the genus level. Specifically, the sounds of Serrasalmus species are shorter, louder, and have a shorter pulse period (as determined after correction for standard length). This suggests that sounds can be used to support taxonomy at the genus level as well as the species level.