For 10 points, name this Gorgon slaughtered by Perseus, whose gaze turned people to stone.
One of this woman's sons married Callirhoe and fathered the shepherd Geryon. Droplets of this figure's blood created the poisonous Saharan vipers and the corals of the Red Sea. This "fair-cheeked" sister of Stheno and Euryale was raped by Poseidon in the temple of a certain goddess. After this figure's death, Pegasus came into being and her head was mounted onto the aegis by Athena. This mortal figure was beheaded by a hero who was given a helmet of invisibility and winged sandals. For 10 points, name this Gorgon slaughtered by Perseus, whose gaze turned people to stone.
One of this woman's sons married Callirhoe and fathered the shepherd Geryon.
Medusa