Falsilunatia patagonica is a species of predatory sea snail, a marine gastropod mollusc in the family Naticidae, the moon snails.
This marine species occurs off the Falklands, Argentina, Tierra del Fuego, the Strait of Magellan, Chile and South Georgia .
The size of an adult shell varies between 12 mm and 30 mm.
Minimum recorded depth is 18 m. Maximum recorded depth is 1886 m.