A variety of fish species have proven instrumental in the investigation of evolution, behavior, ecology, and physiology, among many other fields. Many model systems (e.g., zebrafish, guppies, and ...

Peer into any stream in a South American rainforest and you may well see a small shoal of similar-looking miniature catfish. But don't be fooled into thinking that they are all the same species.

Researchers found a new species of armored catfish from streams in northeastern Brazil, according to a new study. Photo by Tencatt LFC, Couto OLP, Santos SA, Sousa LM via Neotropical Ichthyology and ...

An “iridescent” catfish torpedoed through a rushing blackwater river in Brazil, navigating dead leaves and wood. Little did it know it was soon to be discovered as a new species. Once the “large” fish ...