Chumeria

Chumeria, the Garden Planet of the Universe, is the homeworld of the Chimerons. Sometime in the future, it was attacked by the Bannermen and all Chimerions except their Queen, Delta, escaped, with the planet being left barren and rocky.

After defeating the Bannermen on 1959 Earth with the help of the Doctor, she and Billy, a Chimeron converted from a Human, traveled with her daughter to the brood planet to breed a new race of Chimerons. Afterwards they returned to their own time and rebuilt their race on Chumeria. (DW: Delta and the Bannermen)