C. h. haigi Thomas, 1917 C. h. lentulus Thomas, 1919
Haig's tuco-tuco (Ctenomys haigi), known regionally as the Patagonian tuco-tuco, is a hystricognath rodent.[2] Like other tuco-tucos it is subterranean and thus not often observed, although the "tuc-tuc" call of the males can be heard near burrow sites, especially in the early morning. Like most species in the genusCtenomys, C. haigi are solitary, with one adult per burrow.