Holochilus chacarius Thomas, 1906, Ann. Mag. Nat. Hist., ser. 7, 18:446.

TYPE LOCALITY: Paraguay, Chaco, one league N.W. of Concepcion .

DISTRIBUTION: Paraguay; N.E. Argentina.

COMMENT: Formerly included in brasiliensis by Hershkovitz, 1955, Fieldiana Zool., 37:665; includes balnearum; see Massoia, 1976, in Vidal et al., Physis, 35(90):76, and Massoia, 1980, Ameghiniana, 17:280- 287. Karyology reviewed by Riva et al., 1977, Physis, 36(92):215-218. OAR considers balnearum a distinct species.