Genetic and morphological characteristics and distribution of the Ryukyuan subspecies of ayu Plecoglossus altivelis.

点击翻译按钮获取中文摘要

Genetic and morphological characteristics and distribution of the Ryukyuan subspecies of ayu Plecoglossus altivelis were examined.A new allele substituion was discovered between the Ryukyuan and Japanese subspecies. Average genetic identity between them was 0.78, suggesting that the two subspecies share in common only 78% of total structural genes in their genome on the average.Ayu in Yaku Island, where is in the north of the Tokara Channel, showed genetic and morphological characteristics of Japanese subspecies. This fact supports the hypothesis that the both subspecies were separated by the Tokara Channel and have evolved independently.The Ryukyuan subspecies was found only in Amami-oshima Island. Populations of this subspecies in Okinawa Island probably be extinct. Remnant populations in Amami-oshima Island should be protected.