Specifically, it is found in:
* Brazil: The Amazon River and its tributaries, as well as some lakes and flooded forests.
* Peru: The Amazon River and its tributaries, including the Ucayali and Marañón rivers.
* Guyana: The Essequibo River.
* Venezuela: The Orinoco River.
* Colombia: The Amazon River and its tributaries.
It's important to note that Arapaima populations are declining due to overfishing and habitat loss. Conservation efforts are underway to protect this remarkable fish.