Described to science in 1844, it was thought there was only a single species of Asian arowana until 2003, when a team of three ichthyologists determined that there were actually four species. These had previously been considered color phases (like black leopards or jaguars, or white tigers). This classification is controversial. All populations of the Asian arowana are considered endangered, primarily due to habitat destruction. In the past, they were considered threatened by the commercial aquarium trade, but farm-raised specimens, sold micro-chipped, with “birth certificates” now supply the demand for these “Dragon Fishes”, which, in some Asian traditions, are considered to bring luck to businesses where they are kept.
Though the Silver and Black arowanas of South America, and the Asian and Australian arowanas resemble each other, and share the behavior of brooding their eggs and fry in their mouths, they last shared a common ancestor around 170 million years ago, when the great Southern Continent Gondwana began to split apart. This took place in the Jurassic period, when dinosaurs still thrived. Although Asian arowanas are endangered, South American ones are abundant, and are important both to subsistence fishing and the sustainable aquarium trade.