Csuzdi Csaba, Koo Jachoon, Hong Yong
Department of Zoology, Eszterházy Károly Catholic University, Eger, Hungary.
Division of Science Education and Institute of Fusion Science, College of Education, Jeonbuk National University, Jeonju 54896, Republic of Korea.
Zookeys. 2022 Apr 29;1097:167-181. doi: 10.3897/zookeys.1097.80216. eCollection 2022.
Composting earthworms of the genus play an important role in soil ecosystems. However, taxonomic classification of this genus, especially the sibling species and , is complicated because of their morphological similarity. In this study, we assessed the utility of the complete mitochondrial genome (mitogenome) for identification and differentiation of the two species. The complete mitogenomes of and were 15,714 and 16,560 bp, respectively. They contained 37 genes, comprising 13 protein-coding genes (PCGs), two rRNA genes, 22 tRNA genes, and a putative non-coding region, as observed in other earthworms. Sequence comparisons based on the complete nucleotide sequences excluding the non-coding region showed 85.8% similarity, whereas the predicted amino acid sequences of the 13 PCGs were 92.7% similar between the two species. In particular, distinct features were found in the non-coding regions of the mitogenomes. They include a control region associated with putative mitogenome replication and an extended sequence. The extended sequence showed significant differences between the two species and other known earthworm species, suggesting its potential as a feasible molecular marker for species identification. Phylogenetic analysis of the 36 mitogenomes of earthworm species corroborated the monophyly of the genus and the taxonomic distinctness of the sibling species pair, and .
属的堆肥蚯蚓在土壤生态系统中发挥着重要作用。然而，由于该属的形态相似性，其分类，尤其是姊妹种和的分类很复杂。在本研究中，我们评估了完整线粒体基因组（线粒体基因组）在这两个物种鉴定和区分中的效用。和的完整线粒体基因组分别为15,714和16,560 bp。它们包含37个基因，包括13个蛋白质编码基因（PCG）、2个rRNA基因、22个tRNA基因和一个推定的非编码区，这与其他蚯蚓中观察到的情况一致。基于排除非编码区的完整核苷酸序列的序列比较显示相似性为85.8%，而两个物种之间13个PCG的预测氨基酸序列相似性为92.7%。特别是，在线粒体基因组的非编码区发现了明显特征。它们包括一个与推定的线粒体基因组复制相关的控制区和一个延伸序列。该延伸序列在两个物种和其他已知蚯蚓物种之间显示出显著差异，表明其作为物种鉴定可行分子标记的潜力。对36个蚯蚓物种线粒体基因组的系统发育分析证实了属的单系性以及姊妹种对和的分类独特性。
