Chinchillidae

The family Chinchillidae is in the order Rodentia and consists of the chinchillas, the viscachas, and their fossil relatives. This family is restricted to southern and western South America, mostly living in mountainous regions of the Andes, except one species living on plains. They are medium to large-sized rodents, weighing from to , with strong hind legs and large ears and a bushy tail. All species have thick, soft fur, which is considered valuable in some cultures.

==Characteristics== Members of the family Chinchillidae are somewhat rabbit or squirrel-like rodents varying in weight from . They have large eyes, medium-sized ears, soft dense fur and short bushy tails. The forelegs are shorter than the hind legs. The forefeet have four toes while the hind feet have four small-clawed toes in Lagidium and Chinchilla but three large-clawed toes in Lagostomus, a digging species. Their dental formula is and their incisors grow continually throughout their lives. Chinchillids are generally brownish-grey or grey on the dorsal (upper) surface and pale on the ventral (under) surface. Plains viscachas have distinctive black and white markings on their faces.