Michel Roggo / Matrincha (Brycon sp.) on surface of Rio Negro tributary, Amazon Basin, Brazil. Photographed for The Freshwater Project

Michel Roggo / Piraputanga (Brycon hilarii) and small Tetra fish (Hyphessobrycon sp.) Rio Olhio d'Agua, tributary of Rio da Prata, Serra da Bodoquena (Bodoquena Mountain Range), Mato Grosso do Sul, Brazil Novemb...

Michel Roggo / Piraputanga (Brycon hilarii) Aquario Natural, Rio Baja Bonito, Serra da Bodoquena (Bodoquena Mountain Range), Mato Grosso del Sul, Brazil. Photographed for The Freshwater Project

Michel Roggo / Matrincha (Brycon sp.) in the flooded forest of the Amazon Rio Negro tributary, Amazon, Brazil, February 2011. Photographed for The Freshwater Project

Michel Roggo / Pacu (Piaractus mesopotamicus) and Piraputanga (Brycon hilarii) and Tetra (Hyphessobrycon sp.) Rio Olhio d'Agua, tributary of Rio da Prata, Serra da Bodoquena (Bodoquena Mountain Range), Mato Grosso d...

Michel Roggo / Piraputanga (Brycon hilarii) Rio Olhio d'Agua, tributary of Rio da Prata, Bonito area, Serra da Bodoquena (Bodoquena Mountain Range), Mato Grosso del Sul, Brazil. Photographed for The Freshwater Proje...