Class [Mammalia] Linnaeus, 1758 - mammals Order Rodentia Bowdich, 1821 - rodents Family Chinchillidae Bennett, 1833 - viscachas and chinchillas 1 Genus Lagostomus Brookes, 1828 - plains viscacha 2 Genus Lagidium Meyen, 1833 - mountain viscachas 3 Genus Chinchilla Bennett, 1829 - chinchillas