| Microtheriomys Temporal range:   | |
|---|---|
|  Scientific classification   | |
| Kingdom: | Animalia | 
| Phylum: | Chordata | 
| Class: | Mammalia | 
| Order: | Rodentia | 
| Family: | Castoridae | 
| Subfamily: | † Agnotocastorinae | 
| Tribe: | † Anchitheriomyini | 
| Genus: | † Microtheriomys | 
| Species: | †M. brevirhinus  | 
| Binomial name | |
| †Microtheriomys brevirhinus Korth & Samuels, 2015  | |
Microtheriomys is an extinct genus of anchitheriomyine castorid that lived during the Arikareean.
Microtheriomys brevirhinus is known from the John Day Formation of Oregon. [1]