Thonner was a planet located within the Thonner system of the Outer Rim Territories. Its salty, shallow seas were broken with short chains of sandy islands, such as the Lesser Firagh Peninsula and the Great Zoun Archipelago with freshwater springs discovered 25 BBY. These islands were eventually overgrown with lichen introduced accidentally from Maya Kovel. The planet was home to the tree-dwelling amphibian creatures known as Corsits. The planet served as an Ayrou penal colony and was also settled by Humans and Kian'thar from the Republic, whose descendants were fishermen of cxalas and Thonnerwrot. The planet had .95 standard gravity, 21 standard hours in a local day, and 312 local days in a local year.