The boa constrictor is a non-poisonous tropical snake belonging to a specialized group of reptiles -- the first vertebrate class completely independent of water. It is found in Central and South America and often reaches lengths of up to 4 m (13 ft.). It belongs to the same family as the python and anaconda, which reach lengths of up to 9 or 10m. The boa constrictor's life span is about 25 to 30 years. Some boas live in underground holes while others live in trees.

The Chaco tortoise is a moderately sized tortoise native to the Chaco regions of Argentina, Paraguay and Bolivia. Despite their species name, they are not found in Chile. Chacos are the smallest of the Geochelone tortoises, the largest of which includes the Galapagos tortoises. Chacos are related to the yellow-footed (G. denticulata) and the red-footed (G. carbonaria) tortoises.
The primary threats facing the Chaco tortoises include the two most common facing other threatened populations: habitat destruction and the pet trade, with the biggest impact on wild populations being from the latter.