Region-exclusive Pokémon

Region-exclusive Pokémon, also known as regional Pokémon, are group of Pokémon that are exclusive for specific regions in the real world and are available for capture only by encountering them in wild—in these specific regions. Currently in game there are six Pokémon that are region-exclusive.

Kanto
There are four region-exclusive Pokémon from the Kanto region:

Johto
There are two region-exclusive Pokémon from the Johto region: