云南南部3产地泽蛙核型比较研究

对采自云南个旧、绿春、江城3地的泽蛙进行染色体核型分析。结果表明，3地的泽蛙核型均为2n=26（5L＋0M＋8S），NF=52，染色体次缢痕均出现在6p上。个旧大屯泽蛙的No．3为SM染色体，其余染色体均为M染色体；绿春大黑山的泽蛙No．2、6、7为SM染色体，其余均为M染色体；江城康平的泽蛙No．2、9均为SM染色体，其余为M染色体，显示出不同地区泽蛙核型的差异性。比较了滇南3地和国内外不同地区泽蛙染色体核型变化，结果显示，染色体核型模式及其大型染色体组比较稳定，但次缢痕位置不稳定，小型染色体组变异较大。根据泽蛙次缢痕的地理演化趋势，推测次缢痕位于7p上是一种原始类型，位于6p上是一种较为进化的类型，位于9p上是一种特化的类型。泽蛙的分布及核型分化与第三纪欧亚大陆边缘断裂形成日本海有关，也与第四纪冰期气候变化和随之产生的泽蛙南迁北移有关。

Karyotypic Comparisons Rana limnocharis among Three Regions in Southern of Yunnan

The karyotype of Rana limnocharis is analyzed by samples collected from Gejiu,Luchun and Jiangcheng.The results demonstrate that different samples have the same karyotype,2n=26(5L+0M+8S),NF=52,and the secondary constriction locates on 6p.The chromosome No.3 of Rana limnocharis from Datun of Gejiu is SM,while the rest chromosomes are M.The chromosome No.2,6 and 7 from Daheishan of Luchun are SM and the rest are M.The chromosome No.2 and 9 from Kangping of Jiangcheng are SM,and the rest are M.The frog karyotypes from different localities show diversities.A change trend of karyotypes of Rana limnocharis is compared among the three regions of Yunnan and other regions of China and abroad.The results indicate that the model of karyotype and macro-chromosome group are more stable,the location of the secondary constrictions is unstable and micro-chromosome group varies greatly.Finally,based on geographic evolutionary trend of the secondary constriction,the authors inferr that the secondary constriction located on 7p is the original type,the one located on 6p is an evolutionary type,and the one located on 9p is a special type.The distribution of Rana limnocharis and differentiation of its karyotype involved the formation of Japan Sea caused by Japan disconnected from Eurasia in Tertiary as well as the changes of climate effected by the ice age in Quaternary,which caused the migration of Rana limnocharis south and north.