Mol Biol Rep. 2013 Oct;40(10):5943-52. doi: 10.1007/s11033-013-2701-5.
Lac insects are commercial scale insects with high economic value. The combined molecular phylogeny of 20 lac insect populations was generated using elongation factor 1 alpha, mitochondrial cytochrome c oxidase subunit I and the small subunit ribosomal RNA gene loci. The 20 populations of lac insects clustered into four distinct clades supported by high bootstrap values in maximum parsimony, maximum likelihood and Bayesian analyses. Clade A at the base of the dendrogram comprises Kerria ruralis and two populations of Kerria lacca and is the branch with most primitive species. Clade B includes K. lacca, Kerria sindica and the three populations P, V and Z from India. They clustered with high bootstrap support and have evolved later than those in Clade A. The three unidentified populations P, V and Z exhibited a close relationship with K. lacca and are the same species. In Clade C, three populations of Kerria yunnanensis (Ym, Yj and Yl), population Ys from Thailand and population H from India clustered as a group, in which population H clustered with Ym with 100 % bootstrap in all three analysis methods. In Clade D, Kerria chinensis, Kerria pusana and three populations of K. yunnanensis clustered together with strong support, and are located in the upper branches of the dendrogram and are recently evolved taxa. The majority of populations from the Indian subcontinent clade are more closely related to outgroup taxa from the primitive family Pseudococcidae, as compared to the Eurasian populations. Phylogenetic analysis reveals that the Indian subcontinent is the centre of original of lac insects which have translocated to the Eurasian Continent. Based on the theory of continental drift and existing fossil records, it is suggested that lac insect evolved from ancient scale insects during the late Cretaceous period when the Indian subcontinent drifted towards the Eurasian Continent. Changes in the global environment have impacted on the distribution and evolution of lac insects during the mid-Cretaceous and early Cenozoic. With increasing temperatures lac insects are likely to translocate to subtropical areas.
紫胶虫是一种具有高经济价值的商业性昆虫。采用延伸因子 1α、线粒体细胞色素氧化酶亚基 I 和小亚基核糖体 RNA 基因座对 20 个紫胶虫种群的综合分子系统发育进行了研究。在最大简约法、最大似然法和贝叶斯分析中，20 个紫胶虫种群聚集成 4 个不同的分支，支持率很高。在系统发育树的底部，分支 A 包含了角倍蚜和两个角倍蚜种群，是最原始的物种分支。分支 B 包括了 K. lacca、K. sindica 和来自印度的三个种群 P、V 和 Z。它们与高支持率聚类，比分支 A 进化得晚。三个未识别的种群 P、V 和 Z 与 K. lacca 密切相关，是同一物种。在分支 C 中，三个云南紫胶虫种群（Ym、Yj 和 Yl）、泰国的 Ys 种群和印度的 H 种群聚集成一组，其中 H 种群在所有三种分析方法中都与 Ym 聚类，支持率为 100%。在分支 D 中，K. chinensis、K. pusana 和三个云南紫胶虫种群聚类在一起，支持率很强，位于系统发育树的上枝，是最近进化的分类群。与欧亚种群相比，来自印度次大陆的大多数种群与原始科伪叶螨科的外群分类群更为密切相关。系统发育分析表明，印度次大陆是紫胶虫的起源中心，它们已经迁移到欧亚大陆。根据大陆漂移理论和现有的化石记录，紫胶虫是在白垩纪晚期，当印度次大陆向欧亚大陆漂移时，从古代的介壳虫进化而来的。中生代中期和新生代早期，全球环境的变化影响了紫胶虫的分布和进化。随着温度的升高，紫胶虫可能会迁移到亚热带地区。
