The Pira-nu, “black fish”, is born in old timber canoes lost in the rapids. This Argentinian fish is of great size, with a horse-like head and big eyes. It swims at the surface of the water to capsize canoes, and it quickly devours humans and livestock that have fallen into the water.
Ambrosetti, J. B. (1917) Supersticiones y Leyendas. La Cultura Argentina, Buenos Aires.