Mesomys is a genus of rodents belonging to the family Echimyidae, commonly known as spiny rats. These animals are primarily found in the tropical forests of South America, particularly in countries like Brazil and Colombia. Mesomys species are characterized by their dense fur and spiny quills, which provide protection from predators. These rodents are typically nocturnal and arboreal, meaning they are active at night and spend much of their time in trees. Mesomys primarily feeds on fruits, seeds, and other plant materials, playing a vital role in their ecosystem as seed dispersers.