From Bulbapedia, the community-driven Pokémon encyclopedia.
Lara Laramie (Japanese: Fūko Laramii) is a one-time character in the Pokémon anime. Her English voice actress is Lisa Ortiz.
Lara's only appearance came in The Flame Pokémon-athon. She and her family own the Laramie Ranch, an area just outside of the Safari Zone. Lara and her Ponyta and Growlithe helped guard the ranch from Pokémon poachers.
Lara was going to enter a race with her Ponyta. But Team Rocket, working for Dario, caused an accident that lead to her breaking her arm. Lara was saddened, but quickly realized that Ash could ride her Ponyta in the race.
Ash and Ponyta entered the race, and they were able to successfully defeat Dario, and all the other trainers, and win the race. In the process, Lara's Ponyta evolved into a Rapidash.
In the manga
The same thing happened in The Electric Tale of Pikachu, only that time, Dario wounded her without Team Rocket's help.
This is a listing of all of Lara Laramie's Pokémon in the anime.