A new species of Amazonian fish, Pyrrhulina punctata, has been discovered in Peru, revealing previously unknown biodiversity ...

Older than dinosaurs, these 8 ancient fish existed millions of years earlier and some still survive today in oceans, rivers and deep waters.

The tiny Amazon molly (Poecilia formosa) has always fascinated researchers because, according to the rules of evolution, it shouldn't have survived as a species, let alone thrive as a species for over ...