Li Ran, Ying Xiaoli, Deng Weian, Rong Wantao, Li Xiaodong
College of Life Sciences, Nanjing Normal University, Nanjing, China.
School of Chemistry and Bioengineering, Hechi University, Yizhou, China.
PeerJ. 2021 Feb 2;9:e10523. doi: 10.7717/peerj.10523. eCollection 2021.
Scelimeninae is a key member of the pygmy grasshopper community, and an important ecological indicator. No mitochondrial genomes of Scelimeninae have been reported to date, and the monophyly of Scelimeninae and its phylogenetic relationship within Tetrigidae is still unclear. We sequenced and analyzed eight nearly complete mitochondrial genomes representing eight genera of Scelimeninae. These mitogenomes ranged in size from 13,112 to 16,380 bp and the order of tRNA genes between COII and ATP8 was reversed compared with the ancestral order of insects. The protein-coding genes (PCGs) of tetrigid species mainly with the typical ATN codons and most terminated with complete (TAA or TAG) stop codons. Analyses of pairwise genetic distances showed that ATP8 was the least conserved gene within Tetrigidae, while COI was the most conserved. The longest intergenic spacer (IGS) region in the mitogenomes was always found between tRNA and ND1. Additionally, tandem repeat units were identified in the longest IGS of three mitogenomes. Maximum likelihood (ML) and Bayesian Inference (BI) analyses based on the two datasets supported the monophyly of Tetriginae. Scelimeninae was classified as a non-monophyletic subfamily.
棱蝗亚科是矮蝗群落的关键成员，也是重要的生态指示物种。迄今为止，尚未有棱蝗亚科线粒体基因组的报道，棱蝗亚科的单系性及其在癞蝗科中的系统发育关系仍不明确。我们对代表棱蝗亚科8个属的8个近乎完整的线粒体基因组进行了测序和分析。这些线粒体基因组大小在13,112至16,380 bp之间，与昆虫的祖先顺序相比，COII和ATP8之间的tRNA基因顺序发生了反转。癞蝗科物种的蛋白质编码基因（PCGs）主要以典型的ATN密码子起始，大多数以完整的（TAA或TAG）终止密码子结束。成对遗传距离分析表明，ATP8是癞蝗科中最不保守的基因，而COI是最保守的。线粒体基因组中最长的基因间隔区（IGS）总是位于tRNA和ND1之间。此外，在三个线粒体基因组的最长IGS中鉴定出了串联重复单元。基于这两个数据集的最大似然（ML）和贝叶斯推断（BI）分析支持癞蝗亚科的单系性。棱蝗亚科被归类为一个非单系亚科。
