Malleon

Malleon was the home planet of the Calaxi.

Driven from their breeding grounds, the Spherions were drawn to the biology of Calaxi, colonizing them. When Malleon was made worthless to them, the Calaxi fled their planet. (COMIC: Music of the Spherions)

According to the Ninth Doctor, the Cyber-Empire eventually annexed the planet "a decade or two" before the 5320s. (COMIC: The Bidding War)