Frost Lepus was a rabbit-like animal from Calufrax Major.
They had white fur, black eyes and pink nose. A Frost Lepus sitting on its haunches was a tall as a human. They moved by leaps and could hear high frequencies inaudible for humans. They ate carrots.
The Thirteenth Doctor, Graham, Ryan and Yasmin tethered four Frost Lepuses to two sledges to get from the TARDIS to the Galactic Seed Vault. (PROSE: The Secret in Vault 13)