Comparative Morphology of the Male Genitalia of Japanese Muroidea Species

We examined the morphology of male genitalia six Muridae and five Cricetidae in Muroidea focusing on medial lateral bacular mounds, as well their ossification patterns to discuss diversity movement mechanism trident structure. All species possessed a mound two which collectively formed In species, was ossified or consisted cartilage, while mounds were composed soft tissue. By contrast, both species. Among developed, small Mus Micromys highly developed Apodemus speciosus. Different combinations developmental characteristics produced variation glans penis morphology. Histological examination A. speciosus Craseomys rufocanus suggested that driven by blood flowing into cavernous space, increases cross-sectional area penis.