From the family of cartilaginous fishes which includes sharks, stingrays have electrical sensors called ampullae of Lorenzini, used to sense electrical charges given off by potential victims.
When courting a female, the male will chase her, and continually bite her pectoral disc.
Rays have been known to keep sperm stored in order to delay birth until the time is right.
In London zoo two female stingrays delivered 7 pups amazingly neither of them had been anywhere near a male for 2 years!