Abstract
In South America, particularly in the Amazon region, two endemic species of the Osteoglossiformes order are found, the silver arowana (Osteoglossum bicirrhossum) and the black arowana (O. ferrerai), which diverged about 6 million years ago. While the silver arowana, occurs with a wide distribution in the Amazon and Orinoco basins, and the Rupununie and Oiapoque rivers (clear waters), the …