基于COⅠ基因的分子系统发育分析在蚋科昆虫鉴定中的应用

Application of Molecular Phylogeny Based on Mitochondrial COⅠ Gene in Identification of Simuliidae

蚋的种类繁多,其不同发育虫期在形态学上具有高度的相似性,通过形态学特征对虫株进行鉴定具有极大的困难,且目前尚无公认的分类系统。从分子水平结合形态学特征对蚋科类群进行整理,应能使蚋科昆虫鉴定更为准确,分类系统更能反映其生物谱系。以COⅠ基因的特定区段作为"条形码"为生物编码,可实现物种鉴定的便捷、准确及自动化。本研究对15株蚋科昆虫进行了形态学鉴定及基于COⅠ基因序列的系统发育分析。研究中共采集并成功羽化出蚋科虫株15株,其中14株完成形态学鉴定,COⅠ基因序列分析验证了形态学鉴定结果;L1虫株因操作过程中成虫尾器被破坏,未完成完整形态学鉴定,COⅠ基因序列分析提示其可能为一未知新种或未报道过COⅠ基因序列的已知种。研究结果显示,蚋的形态学鉴定极度依赖鉴定者的经验和熟练的技术,严重制约了蚋的鉴定、分类研究的发展,COⅠ基因序列分析能较好建立蚋亚属内种间关系。

There are a lot of Simuliidae species, which have high similarity in morphology of their different devel- opmental phases. It is very difficult to identify the strains by morphological characteristics. Meanwhile, there is no universal approbated classification system of Simuliidae at present. Emending Simuliidae taxa from the molecular level in combination with the morphological characteristics should be able to make more accurate identification of Simuliidae insect and establish a classification system that can better reflect the biological lineage. It can realize the convenient, accurate and automatic species identification with the particular segment of CO I gene as a ＂bar code＂ for the biological encoding. 15 strains of Simuliidae insect were carried out morphological identification and phylogenetic analysis based on CO I sequences in this study, in which 14 strains of Simuliidae insect were fin- ished morphological identification and CO I gene sequence analysis verified the results of morphological identifi- cation. The morphological identification of strain L1 was not completed because the genitalia of strain L1 was de-stroyed in the process of operation, but it might be a new species or a known species that was not reported by CO I gene sequence according to molecular phylogeny based on CO l gene. Research results showed that the morpho- logical identification of Simuliidae insect relied heavily on the experience and expertise of skilled technology, and it had seriously restricted the development of identification and classification of Simuliidae. CO I gene could bet- ter discriminate Simuliidae at the genera and species level.