The superb giant land-snail lives only in the north-western part of the South Island, and can often be seen along the Heaphy Track. They feed at night on earthworms, are predominantly nocturnal, lay large calcified eggs (similar to those of birds), grow as large as 90 mm (and can weigh as much as a tui), and they can live for at least 20 years.
Powelliphanta is a genus of about 15 large land-snail species unique to New Zealand. They range throughout the South Island and southern North Island. Most Powelliphanta species and populations are highly endangered due to a mixture of habitat loss, drying conditions, and predators (rats, possums, weka, thrushes, pigs), including P. superba.
Powelliphanta species are protected under the Wildlife Act, but despite this and ongoing conservation efforts, many of these unique NZ land-snails are threatened by mining, logging and other direct human activities. These populations could stand to benefit considerably from some improved funding and public interest, as they are currently dependent on conservation actions for their long-term survival.
Check these links for more info on the Superb Giant Snail in NZ
Wikipedia: Information on the Superb Giant Snail
Department of Conservation: Powelliphanta Snail
Click on the image to visit the official iNaturalist.nz observation.