Vortis

Vortis was a planet in the Isop Galaxy, which was home to various native insectoid species, including the Menoptera, the Optera, the Zarbi and the Venom Grubs.

History
Originally a world of flower forests, the Doctor had visited there in his first incarnation. The native species of the world lived in harmony.

After the invasion of the Animus, the planet had changed into a world with a thin atmosphere, low oxygen, natural crag-like rock formations and pools of acid. With the destruction of the Animus, the Doctor hoped that Vortis could once more regain its verdant beauty. (DW: The Web Planet)

The Doctor visited twice more during his first incarnation. On his second visit he returned to Vortis after the planet had been engineered by the Zarbi Supremo to travel through space and was near the orbit of Jupiter. There he confronted the Zarbi Supremo with the aid of Gordon Hamilton and returned control of the planet to the Menoptera. (DWA: The Lair of Zarbi Supremo)

Many years later, Vortis drifted into the neighboring Rhumos system and became disputed territory for the Rhumons, who were in the midst of a civil war. The Animus, also, had not been completely destroyed, and a seed of it survived. With the destruction of this seed yet again with the help of the Doctor, Vortis eventually was left to regain its beauty and the Rhumons declared Vortis neutral territory and hoped the other Rhumons would learn of this, ending the war and bringing the Rhumos system to peace. (MA: Twilight of the Gods)