The order Paucituberculata contains the six surviving species of shrew opossum. Caenolestes is the main genus, and the group as a whole may be called 'caenolestids'.
They are small, shrew-like marsupials of the Andes mountains of South America.
20 million years ago, there were at least seven genera in South America. Today, just three genera remain. They live in inaccessible forest and grassland regions of the high Andes.