Powelliphanta augusta or the Mount Augustus snail, previously provisionally known as Powelliphanta Augustus, is a species of large, carnivorous land snail, a terrestrial pulmonate gastropod mollusc in the family Rhytididae. Naturally occurring only on Mount Augustus near Westport on New Zealand's South Island, their entire habitat was destroyed by coal mining. The world population was taken into captivity, in theory until their habitat was restored and they could be released. The mining company concerned went bankrupt and habitat restoration has been unsuccessful, so the species' future is uncertain.