The second way taxonomists discover new species is through fieldwork at places unexplored or poorly sampled. These images are from expeditions to the Xingu River, Brazil, an Amazonian tributary that was poorly sampled until recently. Funded by the National Science Foundation (NSF DEB-1257813), the so-called iXingu Project was jointly led by Mark Sabaj Perez, interim curator of fishes at the Academy of Natural Sciences of Drexel University; Lúcia Rapp Py-Daniel of the Instituto Nacional de Pesquisas da Amazônia, Brazil, and Leandro Sousa at Universidade Federal do Pará, Campus de Altamira, Brazil. In addition to yielding valuable new museum specimens to study, the fieldwork documented the natural aquatic diversity of the Xingu River prior to its disruption by Belo Monte, the world’s third largest dam complex.