Quigley worked with the Umbrella hit-maker in several of her live performances and danced backup in her music video for 'S. Friends say she was acting strangely before she vanished.
Missy Elliott also tweeted out the dancers image and asked anyone with information to come forward.
Quigley was located on Tuesday and is receiving medical treatment at an undisclosed location.
Shirlene Quigley, 32, of North Bergen, New Jersey, a backup dancer for Rihanna and Beyonce, has been found alive.
On Monday night, Rihanna sent out a plea to fans asking for help finding her.
A friend of the 28-year-old pop singer filmed her cooking up a feast of sweet plantain, bacon, egg whites and toast on app Snapchat.