Favio found this little opossum at the edge of the trail on the Alisos Path. He says it was quiet and then got into the grassland. The size in this position would be 5 cm (without the tail). This opossum is in fact very small and its prehensile tail is longer than its head and body together. It is arboreal and nocturnal. Females lack a pouch.
Up until recently it was known as Gracilinanus agilis chacoensis and now its name has changed to Cryptonanus chacoensis.