From Bulbapedia, the community-driven Pokémon encyclopedia.
This is a list of Pokémon in the order dictated by the Alola regional Pokédex, meaning that the starter Pokémon from Alola will appear first, followed by Pokémon native to the Alola region.
The Alola Pokédex listing for Pokémon Ultra Sun and Ultra Moon mainly follows the concept of the original Alola Pokédex from Pokémon Sun and Moon; with the exception of the Murkrow and Misdreavus lines, the 302 Pokémon from Sun and Moon remain in the same order as in Sun and Moon. However, unlike the Platinum expansion of the Sinnoh Pokédex, where the additional Pokémon were merely appended to the existing list, the 101 additional Pokémon in Ultra Sun and Ultra Moon are interspersed throughout the Pokédex. While the new Alola Pokédex listing follows the original listing up to #023 (Ariados), it diverges starting at #024 (Buneary).
In addition to the overall order, the Alola Pokédex splits Pokémon into four sub-listings: the Melemele Pokédex (Japanese: メレメレ図鑑 Melemele encyclopedia), with 150 Pokémon; the Akala Pokédex (Japanese: アーカラ図鑑 ʻĀkala encyclopedia), with 160 Pokémon; the Ula'ula Pokédex (Japanese: ウラウラ図鑑 ʻUlaʻula encyclopedia), with 160 Pokémon; and the Poni Pokédex (Japanese: ポニ図鑑 Poni encyclopedia), with 130 Pokémon. In-game, the Pokémon in each island's listing retain their general Alola Pokédex number, such as Pikipek's number being #010 in all of the island listings even though it is the first Pokémon in all but Melemele's list.
List of Pokémon by Alola Pokédex number