Powelliphanta is a genus of large, air-breathing land snails, pulmonate gastropods in the family Rhytididae, found only in New Zealand.

Often restricted to very small areas of moist forest, they are prey to introduced mammalian predators, and many species are threatened or endangered.

They were named "in recognition of the great service rendered to the study of the family by Mr A. W. B. Powell", and from their similarity to Paryphanta.

Some species have an extremely restricted distribution, such as Powelliphanta gilliesi brunnea, which is only found in a 1 hectare (2.5 acres) remnant of coastal forest.

[6] Powelliphanta require a moist environment because, unlike other land snails, they cannot seal off their shells with a protective mucous membrane.

[7] The striking delicately patterned shells of Powelliphanta come in an array of shades, from brown or red to yellow or black.

Powelliphanta uses a rudimentary radula to devour their prey: a tongue-like belt of teeth, which scrapes chunks of flesh into the oesophagus.

[citation needed] Habitat modification and trampling by introduced animals like goats, deer, and cows is also a threat.

[5] Controlling predatory mammals is now critical to the survival of Powelliphanta, and many recovery plans are being undertaken by the Department of Conservation.

[citation needed] Between 1994 and 2010, a series of three aerial 1080 operations over 3430 ha of the Ruahine Forest Park resulted in significant increases in Powelliphanta marchanti.