It was in the Med, off the North Coast of Sardinia. Just saw the reaction of the diver when he put his hand on it (looked like a mini epileptic fit - no 'zap' visible from the ray). Painfull but not too dangerous. Before the dive he was mouthing off about how great a diver he was - this shut him up.
The real 'nasty' though is the stone fish, which you get in the Red Sea. Stand on one of those and you can be dead within 30 minutes from herat failure.
Incidentally, the electric ray is not that big - sort of like a small 'squarish' sting ray and with a speckled pattern on its back. Quite distinctive.
As for stingrays, we sometimes get them off the UK coast and they seem to be prolific in the warm water at the outlets of nuclear power stations on the SE coast !