The Urar mouse-like hamster or Azerbaijani mouse-like hamster (Calomyscus urartensis) is a medium-sized mouse-like hamster from Nakhichevan, Azerbaijan and northwestern Azarbaijan Province, Iran. It is among the better studied representatives of this poorly known genus. The initial species description was based on a unique chromosome number (2n=32; FNa=42) called a karyotype. The species status has been confirmed with other chromosomal studies and morphometric studies. The species description by Vorontsov et al.[1] and subsequent prompted elevation of several subspecies of Calomyscus bailwardi to species status.