Species of rodent
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The ash-colored Oldfield mouse (Thomasomys cinereus) is a species of rodent in the genus "Thomasomys". It is found in montane forests of the Department of Cajamarca in northern Peru, at elevations of . Until 2023, it was thought to be more widely distributed, ranging into southern Ecuador, but these populations are now identified as three separate, closely related species, "T. lojapiuranus", "T. pagaibambensis", and "T. shallqukucha".
With a head-body length of , "Thomasomys cinereus" is a medium-sized species for the genus. Distinguishing characteristics compared to its close relatives include, among others:
References.
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