Dory, a character in Pixar's "Finding Nemo" (2003) and the forthcoming "Finding Dory" (2015), is a blue tang fish. Blue tangs, also known as Paracanthurus hepatus, are a species of Acanthuridae, or surgeonfish. Dory is voiced by Ellen DeGeneres in both "Finding Nemo" and its sequel.
Blue tangs are the only member of the genus Paracanthurus and are also called blue hippo tangs, regal blue tangs, flag tail surgeonfish or royal tangs, among other names. As depicted in the film, blue tangs have a distinctive royal blue body with a yellow tail; however, they are not to be confused with the yellowtail tang, which is a separate species.