I heard that africa has some native freshwater sting rays. How come i never see them in the aquarium Biz...are they too big? I also hear the same about asia
The ray to which you are refering is from Cross River , It is brown and nonedescript for the effort and the price it is not commercialy viable.
It does look like a himantura from Asia .
I will find the photo I have of it from my workplace .