Alphacoronaviruses and betacoronaviruses may all originate from bat viruses, but the subgenus Embecovirus contains many viruses infecting rats (in addition to mouse coronavirus, there are also the Lucheng Rn rat coronavirus, China Rattus coronavirus HKU24 and Myodes coronavirus 2JL14, with a large number of related virus strains found since 2015), and no bat virus has been found.
Alphacoronaviruses and betacoronaviruses are thought to have originated from bats, but the subgenus Embecovirus contains many viruses that infect rats (including mouse coronavirus, Lucheng Rn rat coronavirus, China Rattus coronavirus HKU24, and Myodes coronavirus 2JL14), while no bat virus has been found within this group.