Bushrats

The common Bushrat of Mars is similar to the Earth rat: an annoying pest. Despite the sharp beak, a single Bushrat is no threat at all. Too bad that they usually travel in huge packs to overwhelm their prey.

The bushrat is also strange since despite being a plant-animalt, it lives above and below ground. Thsi indicates that it doesn't need sunlight, unlike other plant animals.

Lore
''Here is a curious anomaly -- one of the few plantimals to be found, both above and below ground. How these rat-like scavengers survive without the light of the sun so necessary to other plants is a mystery. Perhaps it is akin to Earth saprophytes -- non-photosynthesizing plants that survive on decaying organic matter. Bushrats can be found everywhere, feeding on the remains of dead worms and the kills of surface-dwelling carnivores. Small, quick and blessed with razor sharp teeth and claws, bushrats are surprisingly dangerous when provoked.''

- from "Mysteries of the Red Planet", Martian Dreams