大分県大分川水系から得られたシマドジョウとその生物地理学的起源
2004 年 51 巻 2 号 p. 117-122
詳細
2004 年 51 巻 2 号 p. 117-122
The distribution range of the Japanese spined loach Cobitis biwae is in the middle stretches of rivers in most of Honshu and Shikoku Islands. In Kyushu Island, its close relative, the yamato complex sensu Saitoh et al.(2000), is distributed, but C. biwae is thought to be absent there. Comparison of the morphological characters and erythrocytic size revealed that the specimens of Cobitis collected from the Oita River system in Kyushu Island are the tetraploid form of C. biwae. Subsequent mitochondrial DNA analyses also supported this finding. Taking the connection pattern of drainages during glacial periods into consideration, it is suggested that C. biwae from the Oita R. s. is native.
