Rill

Rills were a peaceful and advanced telepathic race. They required ammonia to breathe and were considered hideous in appearance by many humanoid races.

One Rill ship was attacked by a Drahvin ship and the two crashlanded on an uninhabited, doomed planet. The Rills sent out their robot Chumblies to contact the Doctor, who had also arrived on the planet, and convinced him to help them escape the planet. (DW: Galaxy 4)

The Rills had a political system in which the uglier one was, the more power one attained. (NA: Lucifer Rising)

Rills visited Kirith and were taken to Kandasi Island, where they were presumably killed. (NA: Timewyrm: Apocalypse)