The giant freshwater stingray may be the world’s largest freshwater fish. It’s also cloaked in mystery. No one is sure how many giant stingrays are left, which habitats they prefer, or even if they ever venture into the ocean, where their more commonly known relatives live.

These ancient fish, little changed over many millions of years, can reach 16.5 feet long, including the tail. There are reports of giant stingrays weighing up to 1,300 pounds, though such accounts are not verified because weighing the enormous and awkward animals is very difficult.

Brown to gray in color, the giant stingrays are wide and flat in form, and they sport long, whip-like tails. They are known to prowl river systems in