Shedinja is a Bug, Ghost-type Pokémon from Hoenn region. It doesn't evolve into nor from any other Pokémon, however it is a member of Nincada's family.
Shedinja - Shed Pokémon
Shedinja's hard body doesn't move—not even a twitch. In fact, its body appears to be merely a hollow shell. It is believed that this Pokémon will steal the spirit of anyone peering into its hollow body from its back.