游蛇科4种的核型比较

COMPARATIVE STUDY ON THE KARYOTYPES OF FOUR SPECIES IN COLUBRIDAE

以骨髓细胞直接制备染色体标本，分析了游蛇属（Ｎａｏｔｒｉｘ）３种和链蛇属（Ｄｉｎｏｄｏｎ）１种蛇的核型．草游蛇（Ｎ．ｓｔｏｌａｔａ）２ｎ＝３６，１８（１５Ｍ＋１ＳＴ＋２Ｔ）·１８ｍ（♀）．渔游蛇（Ｎ．Ｐｉｓｃａｔｏｒ）２ｎ＝４０，１６（１０Ｍ＋１ＳＭ＋３ＳＴ＋２Ｔ）·２４ｍ（♀）．乌游蛇（Ｎ．ｐ．ｐｅｒｃａｒｉｎａｔａ）２ｎ＝４０，１８（８Ｍ十２ＳＭ＋８Ｔ）·２２ｍ（♂）．赤链蛇（Ｄ．ｒｕｆｏｚｏｎａｔｕｍ）２ｎ＝４６，２０（１Ｍ＋３ＳＭ＋１６Ｔ）·２６ｍ（♀）．草游蛇和渔游蛇的Ｎｏｓ，赤链蛇的Ｎｏ３为ＺＺ／ＺＷ型性染色体．草游蛇Ｚ染色体为Ｍ型，Ｗ染色体为ＳＴ型；渔游蛇Ｚ为ＳＭ型，Ｗ也是ＳＴ型；赤链蛇Ｚ为Ｍ型，Ｗ为ＳＭ型．三者Ｚ均略大于Ｗ．草游蛇和渔游蛇Ｎｏ４长臂末端有时可见随体．对游蛇属、链蛇属以及游蛇亚科（Ｃｏｌｕｂｒｉｎａｅ）已知各属种的核型进行了比较和讨论．

The karyotypes of four species in Colubridae from Fuzhou were studied by using the method of directly prepering chromosome with marrow cells, and they were found as: Natrrix stolata had 2n= 36, 18 (15M+1ST + 2T)' 18m(♀) ;N. piscator 2n= 40, 16(10M+ 1SM+3ST+2T)' 24m(♀) ;N. percarinata percarinata 2n= 40, 18 (8M + 2SM+ 8T)' 22m (♂ )and Dinodon rufozonatum 2n =46, 20 (1M+ 3SM+ 16T)' 26m (♀). Sexual dimorphism of the chromosomes was represented by No 5 (N. stolata and N. piscator)or NO. 3 (D. rufozonatum) with the ZZ/ZW mechanism,showing female heterogamety. The Z was metacentric, while the W subtelocentric in N. stolata. In N. piscator the Z was submetacentric,while the W subtelocentric too. In D.rufozonatum the Z was also metacentric,while the W submetacentric. All Z was longer than W. The karyotypes of Natrix.Dinodon and other known genera in Colubrinae were also comparatively studied in this paper.