J. Knox Jones, Comments on the Taxonomic Status of Apodemus peninsulae…
“ Three general groups of the genus Apodemus are presently known to occur on the mainland of northeast Asia. One is the distinctive Apodemus agrarius, lone representative of the subgenus Apodemus. The others, both in the subgenus Sylvaemus and closely resembling each other, are represented by a small animal that is currently regarded as conspecific with Apodemus sylvaticus and a larger animal of which the Korean mouse, peninsulae, is representative. ”
