I know a lot of people here prefer to ignore the EU, but just for kicks . . .
From the Wookiepedia article on the Auqualish:
In one of A New Hope's best known continuity errors, Ponda Baba's arm has fin-like hands when still attached, but is hairy and clawed in the close-up shots of the severed arm on the floor. This inspired the writers at West End Games to develop the Aquala and Quara types of Aqualish. Star Wars: The Complete Visual Dictionary retconned the error by creating a new character, Teak Sidbam, said to be sometimes mistaken for Baba.