新疆产捷蜥蜴(Lacerta agilis)染色体的研究

Study of the Karyotype of Sand Lizard Lacerta agilis From Xinjiang

采用常规骨髓细胞制片法，对分布在新疆哈巴河地区捷蜥蜴（Lacerta agilis）种群的染色体组型进行了研究。结果表明，捷蜥蜴的二倍体染色体数为38条，性别决定机制为ZW型，存在异型的性染色体，其中，雄性性染色体为ZZ型，染色体组型为2n=34I＋2m＋ZZ；雌性性染色体为ZW型，染色体组型为2n=34I＋2m＋ZW。捷蜥蜴的染色体除第18对和w染色体呈点状外，其余全部为端着丝点染色体。按照染色体的相对长度将18对常染色体分成3组，第1组包括第1、2、3对染色体（相对长度〉7．5％），第2组包括第4—17对染色体和性染色体（7．5％〉相对长度〉2．0％），第3组只有第18对染色体（相对长度〈2．O％）。除Z和w性染色体不同外，其余染色体的大小和类型均无两性差异。从组型特征来看，为蜥蜴目较原始的类型。

The karyotype of sand lizard Lacerta agilis from Xinjiang Habahe was studied by using medulla cells and the colchicine-hypotonic air-drying technique. The number of diploid chromo- somes of males Was 38（2n =341 ＋2m ＋ZZ）, and sex chromosomes were of the type ZZ. In fe- males there were 38 chromosomes（2n = 341 ＋ 2m ＋ ZW） and sex chromosomes were of the ZW type. The sex determination mechanism depends on sex chromosomes. All chromosomes of males and females were telocentric except for pair number 18 and the W sex chromosomes were spot chromosomes. The chromosomes were matched by shape into 18 pairs and classified by length into 3 groups. The first group（ pairs number 1 to 3, relative length 〉 7. 5% ）, the second group（pairs number 4 to 17, 7. 5% 〉 relative length 〉2.0%）, and the third group（pair number 18, relative length 〈 2. 0% ）. Except for the Z and W chromosomes, the size and type of the re- maining chromosomes did not differ between the sexes. According to karyotypic characteristics, they are all primitive species within Lacertiformes.