Misty's Starmie is a character from Pokémon Adventures.
Staryu and Misty fight against Gyarados; Gyarados knocks out Staryu with Hydro Pump. Red interferes at that moment, giving Staryu time to use Recover and then team up with Red's Bulbasaur to defeat Gyarados.
In the next chapter, it is revealed that Staryu has evolved into Starmie. Misty uses Starmie to attack Red when he refuses to believe that she is Cerulean's gym leader. Red sends out his Bulbasaur, using Vine Whip, which Starmie counters with BubbleBeam. The gym battle is not concluded.