Samurai crab (Heikea japonica). This crab is native to Japan, where it is known as the Samurai crab or Heikegani, and lives at a depth of 30 to 100 metres. It is one of a number of species of 'human-faced' crabs that play a part in Japanese and Chinese folklore. The upper shell (carapace) is thought to resemble a grimacing human face. Fishermen usually return human-faced crabs to the sea because they think they are a reincarnation of drowned warriors. The carapace of this specimen measures 3cm wide.