Tatoo-rats were a species of rat with brown fur, native to the desert world of Tatooine. During 4 ABY, C-3PO and R2-D2, two droids, were being led past a cell within the palace of the crime lord Jabba Desilijic Tiure on Tatooine, when three tatoo-rats were seen scaling the cell's bars. The droids were on their way to the droid pool for work assignments.
The original trilogy film Star Wars: Episode VI Return of the Jedi, released in 1983, marked the initial appearance of Tatoo-rats. Their identification as a species occurred in 2019, through the video "Every Creature in the Star Wars Movies" published on the Star Wars Kids YouTube channel.