This tuco-tuco is recorded from coastal and west-central Chubut, Argentina. The original paper describes a brownish-olive back and a pale underside.
Its fur is dense, fine, and soft. The back ranges from light brownish olive to brownish olive; the underside is pale olive buff with gray hair bases.
The paper says natural history is mostly unknown. Four coastal localities assigned to C. c. contrerasi are in Monte shrub-steppe, dominated by Larrea shrubs with vegetation cover usually below 40%. This is habitat at those collection sites, not a species-wide preference.
An extinction-risk assessment has not been added yet.