Rio Baía is a clearwater spring river located in Mato Grosso do Sul, Brazil, flowing through one of South America's most biologically rich freshwater ecosystems. Fed by natural springs, this river is characterized by exceptional water clarity and an extraordinary abundance of aquatic vegetation. The riverbed varies considerably throughout its course, transitioning between sandy stretches, gravel and pebble substrates, and soft clay-like sediments depending on current speed and local conditions. The dense aquatic plant communities — including species such as Guppy Grass (Najas guadalupensis) — create a lush, layered underwater environment that supports an impressive diversity of fish species and invertebrate life.