You found a Charmander!
Charmander, known as Hitokage (ヒトカゲ?) in Japan, is a Pokémon species in Nintendo and Game Freak’s Pokémonfranchise. Created by Ken Sugimori, Charmander first appeared in the video games Pokémon Red and Blue and subsequent sequels, later appearing in various merchandise, spinoff titles and animated and printed adaptations of the franchise. The end of a Charmander’s tail is alight with a flame, and the flame’s size reflects both the physical health and the emotions of the individual.
Charmander was created as one of the first Pokémon and is a starter Pokémon the player can choose from at the beginning of Pokémon Red and Blue, and their remakes, Pokémon FireRed and LeafGreen. In the anime, Ash acquires a Charmander early in the series, and it became one of his most used Pokémon. In the Pokémon Adventures manga, Blue receives a Charmander from his grandfather Professor Oak. Since it appeared in the Pokémon series, Charmander has received generally positive reception.
Charmander evolves into Charmeleon who then evolves into Charizard, which was originally its last form. Since the release of Pokémon X and Y, Charizard can mega evolve into Mega Charizard for the duration of a battle.