Pagurus novizealandiae, or the New Zealand hermit crab is a hermit crab of the family Paguridae, endemic to New Zealand. Its body is up to wide. Description Hermit crabs are usually easy to identify because of the colouration of their antenna and their antennules (a small structure resembling antennae which sits in front of the actual antennae). The hermit crab is approximately about the size of a coin and on average about 56mm in length, but this is slightly limited by the size of the shells available. The crab abdomen is spiral shaped, and can twist and is flexible, so they can fit easily and comfortably into the different shells they take on throughout their life. The crab protects and shields itself from predators and potential danger by contracting rapidly back into its shell out of reach, it uses its large chela as a door which protects it once it has retreated back into the safety of its shell. Throughout their lifetime hermit crabs use and adopt empty mollusk and gastropod shells, such as cats eyes, snails and periwinkles to protect their soft and vulnerable abdomens. The crabs carry their shells around on their backs with small legs which are modified so that their back end can grip into the shell, they use their abdominal muscles to hold the themselves securely in place. Over time, as hermit crabs grow they must switch shells to accommodate their expanding bodies as they need to find larger shells for protection. Distribution Natural global range The Pagurus novizealandiae has not been identified to naturally occur anywhere else in the world as the species is endemic to New Zealand. New Zealand range In New Zealand there are more than 60 known species of hermit crab, predominantly found along the coastline in tidal rock pools and estuaries. Pagurus novizealandiae is mainly found in the intertidal zones right throughout both the North and South Island, however this species is mostly found in the South Island, or on the Auckland Islands 465 km south-east of New Zealand. Habitat preferences The Pagurus novizealandiae is found only in marine environments, around rocky intertidal shorelines or rocky sub tidal reefs. This species of hermit crab cannot tolerate high dilution of seawater at all, therefore cannot survive in freshwater habitats. They are generally restricted to areas, usually the estuary where strong tidal activity takes place and the salinity of the water remains