Holochilus magnus Hershkovitz, 1955 . Fieldiana Zool., 37:657.

TYPE LOCALITY: Uruguay, about 40 km south Treinta y Très, Rio Cebollati, Paso de Averias .

DISTRIBUTION: Uruguay and southernmost Brazil; not recorded from Argentina (Olrog and Lucero, 1981).

COMMENTS: Massoia (1980a) referred Winge's (1887) Hesperomys molitor to Holochilus and noted its close resemblance to H. magnus; their relationship and status warrant additional study (also see Voss and Myers, 1991). Banded karyotypic comparisons of H. magnus and H. brasiliensis presented by Freitas et al. (1983).