The Moleques do Sul guinea pig is known only from a small island off Brazil. It uses a narrow area with grasses and has been reported to breed throughout the year.
Its coarse fur is gray to brown and its body is stocky and cylindrical. It has no external tail and short, hairless ears.
It feeds on grasses in the island's grasslands, and reproduction occurs year-round. Litters are reported to contain one or two young.
An extinction-risk assessment has not been added yet.