Book excerpt: The Middle Paraná river is one of the largest in the world. Exceptionally rich in fauna and flora, it provides researchers with a glimpse into an ecosystem yet undisturbed by human civilization. This fascinating book covers all the key aspects of the Paraná’s fluvial limnology and ecology, arranged in discrete and easily navigable sections. First, the physical and chemical environment is explained, then the river’s plant life, followed by its invertebrate life, and finally the vertebrates that inhabit the river.