This variety of ray is the most common that I have seen in the shallow waters in front of the diving center. The other variety is the feather-tail stingray but so far I have not been able to get close enough for a decent photo.
They are fairly relaxed rays and will allow you to approach them as long as you give them room to move away. They actually do not have ‘stings’ on the base of their tails like the normal stingray. Instead they rely on their tough thorny skin to defend themselves.
This skin was apparently used by the Japanese as sword-grips. You can use that interesting fact to break the ice when meeting people for the first time.