New Electric Knifefish Species Discovered (IMAGE) University of Massachusetts Amherst Caption This image shows Procerusternarchus pixuna, the new species collected in shallow tributaries of the upper Negro river, a tributary of in Amazon River in Brazil. Credit University of Massachusetts at Amherst Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.