Tag Archives: Rhytididae

Powelliphanta augusta Walker, Trewick & Barker

Mount Augustus Predatory Snail (Powelliphanta augusta)

This species was described in 2008, it was until then known under the tag name Powelliphanta “Augustus”. [1]

The Mount Augustus Predatory Snail was discovered in 1996 at the ridgeline of Mt. Augustus northeast of Westport.

This locality was subsequently destroyed by mining operations, and about 6000 snails were taken from the locality in 2007 to protect them from the mine development. The ca. 4000 snails that were released to nearby sites showed an alarmingly high mortality rate, and 800 were even killed accidently by the Department of Conservation in a fridge during a captive program in 2011.



[1] Steven A. Trewick; Kath J. Walker; Corina J. Jordan: Taxonomic and conservation status of a newly discovered giant landsnail from Mount Augustus, New Zealand. Conservation Genetics 9(6): 1563-1575. 2008


Photo: K. J. Walker

(under creative commons license (4.0))

Powelliphanta spedeni (Powell)

Speden’s Predatory Snail (Powelliphanta spedeni)

This species, described in 1932, is endemic to the South Island of New Zealand.

The shell reaches a size of about 4 cm in diameter.

This species is thought to contain two subspecies, the nominate, Powelliphanta spedeni ssp. spedeni (Powell), and Powelliphanta spedeni ssp. lateumbilicata (Powell).


Powelliphanta spedeni ssp. lateumbilicata

Photo: D. Coetzee

(public domain)

Powelliphanta marchanti (Powell)

Marchant’s Predatory Snail (Powelliphanta marchanti)

This species is restricted to the western Ruahine Ranges on the North Island of New Zealand, where it can be found amongst leaf litter in native forest.

Like its congeners, also this is a carnivorous species that feeds upon invertebrates, preferably on earthworms.


Marchant’s Predatory Snail is in decline and highly endangered.


Photo: V. Vercoe

(under creative commons license (4.0))