2017 Volume 57 Issue 2 Pages 217-220
The Ryukyu long-furred rat is an endemic species to Japan, and recognized on the IUCN Red List as “Endangered”. Little is known of its biology. We fortuitously obtained a male Ryukyu long-furred rat suspected to have been killed via a traffic accident on Tokunoshima Island, Kagoshima, Japan in August, 2016, and observed its genitals via light microscopy and scanning electron microscopy to obtain reproductive information on this species. Morphologically matured sperm were found in the epididymis, although they were very few. Spermatogenesis was observed in the seminiferous tubule of its testes. Therefore, the Ryukyu long-furred rat we observed would have had a morphologically matured testis and epididymis, and would have become reproductively functional in this season. Hereafter, we need to gather more information to know the ecological and reproductive traits of the Ryukyu long-furred rat.
