Chaco patagonica is a species of mygalomorph spiders of Argentina, named after its type locality in Patagonia, specifically Chubut Province, Argentina.

[2] The species can be distinguished from C. tecka by not having a patterned cephalothorax and legs, by possessing less maxillary cuspules and by the absence of false preening combs.

[2] The spiders of this species make a small burrow closed with a thin, flaplike door.

The door is made from the silk layer lining the interior of the burrow, covered by grains of sand.

The burrows are about 5 millimetres (0.20 in) in diameter, and 10 centimetres (3.9 in) deep; its walls consist of a silk tube which prevents the sand from collapsing.