Molerats are a type of mutated animal mentioned in Fallout: Equestria - Heroes. No physical description is provided in the side story. It is assumed that they resemble mole rats from the Fallout universe.
Appearances in Side Stories
Molerats are mentioned as one of the creatures commonly found in Caneighda. They are never actually physically described in the side story, although April Showers mentions encountering and defeating them while descending through the ruins of a tall building near a raider nest.