The Proximans were a rodent-like species from Proxima 2.
They were white, stubby-haired creatures. They were semi-intelligent, and were an empathic telepathic species of social animals, with a type of primitive group mind described by the Eighth Doctor as a co-ordination. They lived in nests.
When the the Face-Eater was destroyed, the Proximans ceased to be telepathic or part of a gestalt, thus dooming them to extinction. (PROSE: The Face-Eater)
The second generation human inhabitants of Proxima II were known as Proximans. (PROSE: The Infinity Race)