Kuvangkadilok Chaliow, Boonkemtong Chainarong, Phayuhasena Suwannee, Baimai Visut
Department of Biology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand.
Genetica. 2003 May;118(1):69-81. doi: 10.1023/a:1022909018987.
Larval polytene chromosome maps of Simulium (G.) asakoae and S. (G.) sp. g in the ceylonicum-group and S. (G.) angulistylum, S. (G.) decuplum and S. (G.) siamense in the batoense-group of the subgenus Gomphostilbia from Thailand are presented. These species have three pairs of chromosomes (2n = 6). Light stained centromeric bands were observed in the chromosomes of S. (G.) asakoae, S. (G.) sp. g, S. (G.) decuplum and S. (G.) siamense, whereas heavy dark centromeric bands were present in S. (G.) angulistylum. The best distinguishing character of Simulium species in the subgenus Gomphostilbia is the position of the nucleolar organizer in the short arm of chromosome I. The Ring of Balbiani and the double bubble are located in chromosome arm IIS in all species except for S. (G.) angulistylum, which showed these cytological markers in chromosome arm IIIS. A low chromosomal polymorphism was recorded in all species except for S. (G.) sp. g, which exhibited a standard polytene chromosome. Inversion polymorphisms found in this study conformed to Hardy-Weinberg equilibrium and were not associated with sex. These species have different specific markers and banding patterns although homologous banding sequences were found in chromosome arm IIS in S. (G.) asakoae, S. (G.) sp. g, S. (G.) decuplum and S. (G.) siamense and chromosome arm IIIS in S. (G.) angulistylum. Our results showed no evidence of a sibling species complex within any taxon.
本文展示了来自泰国的戈姆弗斯提尔比亚亚属ceylonicum组的浅黄阿萨蚋和戈姆弗斯提尔比亚属sp. g，以及batoense组的具角蚋、十重蚋和暹罗蚋的幼虫多线染色体图谱。这些物种有三对染色体（2n = 6）。在浅黄阿萨蚋、戈姆弗斯提尔比亚属sp. g、十重蚋和暹罗蚋的染色体中观察到浅染的着丝粒带，而具角蚋的染色体中存在深染的着丝粒带。戈姆弗斯提尔比亚亚属蚋类物种的最佳鉴别特征是核仁组织区在第一号染色体短臂上的位置。除具角蚋外，所有物种的巴尔比亚尼环和双泡都位于第二号染色体臂上，具角蚋的这些细胞学标记位于第三号染色体臂上。除戈姆弗斯提尔比亚属sp. g表现出标准的多线染色体外，所有物种的染色体多态性都较低。本研究中发现的倒位多态性符合哈迪 - 温伯格平衡，且与性别无关。尽管在浅黄阿萨蚋、戈姆弗斯提尔比亚属sp. g、十重蚋和暹罗蚋的第二号染色体臂以及具角蚋的第三号染色体臂中发现了同源带纹序列，但这些物种具有不同的特异性标记和带纹模式。我们的结果表明，在任何分类单元内都没有同胞物种复合体的证据。
