In this study we appraised the dental morphology and potential origin of two Neogene cricetodontine-like muroids, Pliotomodon primitivus from sediments in northern California and an undescribed muroid from central Oregon. Dental features of Pliotomodon are similar to those of Eurasian genera such as Byzantinia, Hispanomys and Ruscinomys, but the unusual morphology of M3/m3, with continuous enamel connections across their lingual surfaces closing the hypoflexus and posteroflexid, respectively, plus retention of only three roots on M1,...