Aridius was a planet originally covered by oceans. Due to a stellar incident, its orbit around its suns left turned the planet into a desert over 1,000 years. The only remaining species were the amphibious Aridians and the octopus-like Mire Beasts.
The First Doctor visited Aridius, but was tracked by the Daleks. (DW: The Chase) Many years later, the Daleks more thoroughly attacked the planet with gravity weapons. (DWBIT: Dalek Wars)