Devario malabaricus the "giant" Danio has been a popular aquarium fish for a very long time. What we've come to realize however is that it is not a single species but rather represents a species-complex that spans from almost Afghanistan to China and as of 2017 there are 37 species. Many people familiar with fish in these areas are quick to point out there are still perhaps dozens of undescribed species in the fast flowing rivers there.
