Although Garcia was previously rumored to be playing the part, TV Line has confirmed the news with an ABC source. Earlier episodes of the show have alluded to her character, and Ariel's upcoming appearance was first confirmed in a Comic-Con teaser for season 3.
Garcia's TV resume includes key roles on The CW's "Reba" and "Privileged," the ABC sitcom "Better with You" and appearances on numerous shows including "How I Met Your Mother." On the big screen, she was recently seen in the comedy "The Internship."
"Once Upon a Time" returns Sunday, September 29.