1901417-626690030713671-1953872431-n-139
 

At half the length of a bus, the gargantuan freshwater stingray (Himantura chaophraya) may well be the largest freshwater fish on Earth. Growing to over 16 feet long and weighing a staggering 1,300 pounds, it faces few contenders for the prize. But despite its mega dimensions, this fascinating species is still cloaked in mystery.

 
Incredibly, H. chaophraya wasn't described by scientists until 1990, and although they are believed to have changed very little over many millions of years, no one is entirely sure which habitats they prefer to inhabit or even how many are left. This mystery is largely due to the fact that they spend most of their time in hiding, burying themselves in sandy or silted river bottoms and breathing through holes on top of their bodies. Like sharks, they locate their preferred food (usually clams and crabs) by detecting their prey’s electrical field.
 
Despite their intimidating size, giant freshwater stingrays are actually quite gentle and inquisitive and do not readily attack humans. But if push comes to shove, they can certainly defend themselves. Each ray is armed with a deadly barb on the base of its tail that can be as much as can be as 40cm long and can easily penetrate bone to inject pain-inducing toxins.
 
Having been unaware of the existence of this gentle giant for so long, Scientists are now desperate to make up for lost time and are racing to study the giant freshwater stingray as, like many large fish species in the Mekong River, it is now endangered.