Greater guinea pig

Cavia magna, commonly known as the greater guinea pig, is a species of rodent in the family Caviidae, native to South America. It is found primarily in the coastal regions of southern Brazil and Uruguay, inhabiting grasslands, marshes, and other wetland environments. Cavia magna is closely related to the domesticated guinea pig (Cavia porcellus) but is distinct in its larger size and semi-aquatic habitat preferences.

This species exhibits adaptations to its wetland habitats, including a preference for dense vegetation near water. Greater guinea pigs are herbivorous, feeding on grasses, sedges, and other vegetation, and play a role in maintaining the ecological balance of their native habitats. Unlike their domesticated relatives, they are not kept as pets and are primarily studied in the context of their ecological and evolutionary significance.