The blue corydoras or Natterer's catfish, Corydoras nattereri, is a tropical freshwater fish belonging to the Corydoradinae sub-family of the Callichthyidae family. It originates in coastal rivers in South America, and is found in the Brazil from Espírito Santo to Paraná. It was originally described by Franz Steindachner in 1876. It is named for Johann Natterrer, its discoverer. The blue corydoras is of commercial importance in the aquarium trade industry.