What is the 1,000th Pokémon in National Pokédex order?

Gholdengo is the 1,000th Pokémon in National Pokédex order.

Gholdengo is a Steel/Ghost-type Pokémon introduced in Pokémon Scarlet and Violet. Its Pokédex number, #1000, was reached during Generation IX, making the species a notable milestone in the franchise’s catalog. It evolves from Gimmighoul after the player collects 999 Gimmighoul Coins.

The design is associated with a humanoid figure made of gold coins, reflecting the coin-collecting evolution requirement. Gimmighoul has two forms: Chest Form and Roaming Form, but Gholdengo is the evolved Pokémon that occupies number 1000.

The milestone is easy to mix up with the number of Pokémon species available at the time. National Pokédex numbering continued beyond 1,000, and later entries include Pokémon such as Pecharunt. The question asks for the specific numbered species, not the total currently known or the number of Pokémon in one regional Pokédex.