Biochemical phylogenetics and historical biogeography of Hynobius boulengeri and H-stejnegeri (Amphibia : Caudata) from the Kyushu region, Japan

摘要

We examined allozymic variation in Hynobius boulengeri, H. stejnegeri, and an unidentified salamander from Amakusa Island, to elucidate the evolution of these salamanders within Kyushu, southern Japan. We found three genetic groups in Kyushu: (1) H. boulengeri from the Sobo-Katamuki Mountains (2) H. stejnegeri from the Kyushu Central Mountains, and (3) H. boulengeri from the Osumi Peninsula and the salamander from Amakusa Island. Collectively, these three groups formed a clade that was geneticallv very remote from H. boulengeri from Shikoku and Honshu. The salamander from Amakusa Island was genetically verb, close to the southernmost poplations of H. bouleneri from the Osumi Peninsula and was judged to be jnegeri also proved to be genetically very, close a population of the Kylushu group of H. boulengeri. Hynobins stejneri to the Kyushn populations of H. boulengeri, and was assumed to represent one lineage, which attained its unique amber body color in the course of differentiation From the ancestral Kyushu stock of H. boulengeri. The three genetic groups are surmised to have been isolated to then present ranges as a result of geohistoric events within Kyushu Island.