Heikegani, sometimes called the "samurai crab," is a species often considered a youkai (creature from Japanese folklore) due to its shell, resembling a human face.
Local belief holds that they are reincarnated spirits of warriors, deceased during the naval battle of Dan-no-ura in 1185. These warriors, called Taira or Heike, gave their name to the crab, Heikegani meaning literally "Heike crab" or "Heike's crab."
Although they are edible, most inhabitants do not eat them. If they're accidentally caught in fishnets, they are usually released.