Woprat

Gallifreyan Woprats were a species long extinct from Gallifrey. The Second Doctor was surprised to fund one in a Type-one TARDIS,and wished to investigate, before Victoria screamed and scared it off. (PDA: Heart of TARDIS)

Appearance
Gallifreyan Woprats were built like small dogs, and appeared like a rat, except it had fifteen long, Multi-jointed limbs arranged similar to that of a spider. Older ones had grey hair that was thin. (PDA: Heart of TARDIS)