Gold3

Her name was Lemon Zest in the reveal and every other PR release regarding her. She's only called Lemon Tart in the movie credits for some reason

Never really paid attention to the credits, due to my copy being a TVRip from Discovery Family in the U.S, which seemed to just use the same credits as the show, but I'm sure her name was Lemon Zest, and I did notice the addition of more human counterparts to the ponies in Equestria.

Might check the credits once I get the DVD in December, though