Although traditionally arranged as a species of Akodon (Cabrera, 1961; Musser and Carleton, 1993), subgenus Chalcomys according to Thomas (1916c), urichi is here assigned to Necromys following those molecular studies that disclose its close relationship to amoenus and lasiurus apart from representative species of Akodon proper (D’Elía, 2003; D’Elía et al., 2003; Smith and Patton, 1993, 1999). Formerly included aerosus as a subspecies (Cabrera, 1961), but karyotypic (Gardner and Patton, 1976) and gene sequence (D’Elía et al., 2003; Smith and Patton, 1993, 1999) data demonstrate their distant relationship (see account of Akodon aerosus).
Morphometric variation of Venezuelan populations studied by Ventura et al. (2000), who recognized meridensis, saturatus, and venezuelensis as subspecies along with the nominate form. Linares (1998) arranged the populations in S Venezuela as a species (saturatus) distinct from those in the Andes (urichi). To date, craniodental morphometrics (Ventura et al., 2000) and cytochrome b comparisons (Smith and Patton, 1999) provide no compelling evidence for doing so, but the biogeographic plausibility of such a divergence merits further attention.