Order Rodentia - Suborder Hystricognathi Author Charles A. Woods text 1993 Smithsonian Institution Press Washington and London Editor Don E. Wilson Editor DeeAnn M. Reeder Mammal Species of the World (2 nd Edition) 771 806 book chapter http://doi.org/10.5281/zenodo.7353083 1-56098-217-9 7353083 Ctenomys knighti Thomas, 1919 . Ann. Mag. Nat. Hist., ser. 9, 3:498 . TYPE LOCALITY: Argentina , Catamarca Prov. , Otro Cerro . DISTRIBUTION: Mountains between Tucumân and La Rioja (W Argentina ), north to Salta . SYNONYMS: viperinus. COMMENTS: Cabrera (1961:550) believed viperinus synonymous with knighti . The chromosome no. is 2n=36.