Complete Mitochondrial Genomes of Three Skippers in the Tribe Aeromachini (Lepidoptera: Hesperiidae: Hesperiinae) and Their Phylogenetic Implications
Xiangyu Hao 1, Jiaqi Liu 2, Hideyuki Chiba3 Jintian Xiao 2 and Xiangqun Yuan2,*
1 College of Life Sciences, Northwest A&F University, Yangling, Shaanxi 712100, China;xyhao@nwsuaf.edu.cn
2Key Laboratory of Plant Protection Resources and Pest Management, Ministry of Education, Entomological Museum, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi 712100, China;jiaq_work@163.com (J.L.);xjt0629@nwafu.edu.cn (J.X.)
3B.P. Bishop Museum, Honolulu, Hawaii 96817-0916, USA;chiba.zootaxa@gmail.com
* Correspondence:yuanxq@nwsuaf.edu.cn; Tel.: +86-1375-998-5152
Received: date; Accepted: date; Published: date
Abstract: The mitochondrial genome is now widely used in the study of the phylogenetics and molecular evolution due to its maternal inheritance, fast evolutionary rate and highly conserved gene content. To explore the phylogenetic relationships of the tribe Aeromachini within the subfamily Hesperiinae at the mitochondrial genomics level, we sequenced and annotated the complete mitogenomes of 3 skippers:Amipittia virgata , Halpe nephele and Onryza maga.All of these mitogenomes are double-stranded and have circular molecules with a total length of 15,333 bp, 15,291 bp and 15,381 bp, respectively. The mitogenomes all contain 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and a non-coding AT-rich region, and are consistent with other lepidopterans in gene order and type. In addition, we reconstruted the phylogenetic trees of Hesperiinae using maximum likelihood (ML) and Bayesian inference (BI) methods based on mitogenomic data. Results show that the 3 Aeromachini species in this study robustly constitute a monophyletic group in the subfamily Hesperiinae, with the relationships Coeliadinae + (Euschemoninae + ((Pyrginae + (Eudaminae + Tagiadinae)) + (Heteropterinae + (Barcinae + Hesperiinae)))). Moreover, our study supports the view that Apostictopterus fuliginosus andBarca bicolor should be placed out of the subfamily Hesperiinae.
Keywords: Aeromachini; mitogenome; mitochondrial DNA; phylogeny
1. Introduction
The family Hesperiidae (skippers) is one of the speciose families in butterflies and consists of about 567 genera and more than 4000 species around the world (Warren, Ogawa, & Brower, 2008), accounting for one-fifth of the world’s butterfly species, though the number is far underestimated. The higher classification of the family had mainly followed Evans (Evans, 1943, 1949, 1951) until Warren et al. inferred the phylogenetic relationship from molecular (three loci) and morphological data of 196 genera (Warren et al., 2008; Warren, Ogawa, & Brower, 2009). And the latest molecular study of 250 hesperiid species from all over the world (W. Li et al., 2019) and its supplementary study (Jing Zhang, Cong, Shen, Brockmann, & Grishin, 2019) showed that the family Hesperiidae should be classified into 12 subfamilies, with the relationship of (Coeliadinae + (Euschemoninae + ((Eudaminae + (Tagiadinae + (Pyrrhopyginae + Pyrginae))) + (Katreinae + (Chamundinae + (Heteropterinae + (Barcinae +Trapezitinae) + Hesperiinae))))))), but this higher classification as well as the phylogeny has not been approved generally. Hesperiinae, the largest subfamily, has been proved to be a distinctly monophyletic group by the previous studies (W. Li et al., 2019; Sahoo et al., 2016; Toussaint et al., 2018; Warren et al., 2009; Jing Zhang et al., 2019), we have provided more comprehensive data support for the phylogenetic research of the groups.
Aeromachini is a large and diversed tribe of the subfamily Hesperiinae and currently contains approximately 130 species in 12 genera, distributed in the Oriental Region, the Paearctic Region, and the Afrotropical Region (Cock & Congdon, 2012; Devyatkin, 1996; Evans, 1949; Huang et al., 2019; Warren et al., 2009; Yuan, Yuan, & Xue, 2015). Most of the genera, except for the genus Halpe , of Aeromachini are distributed in the Sino-Himalayan Subregion. In the previous phylogenetic studies, the tribe is always retrieved as a clade sister to the rest of the Hesperiinae. Two molecular studies within the tribe are known (Y. Li et al., 2019).
The insect mitogenome is a double strand molecule about 15~16Kb in size, typically containing 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), 2 ribosomal RNAs (rRNAs) and a non-coding AT-rich region. In the past few decades, due to its maternal inheritance, fast evolutionary rate and highly conserved gene content compared to nuclear genes, it has been widely utilized to investigate insect taxonomy, phylogenetic relationships, evolution and biogeography (Cameron, 2014; Galtier, Nabholz, Glémin, & Hurst, 2009). In this study we determine the complete mitochondrial genome sequences of 3 skipper species of the tribe Aeromachini and reconstruct the phylogenetic relationships of the family Hesperiidae, combined with other available sequence data in GenBank, and using maximum likelihood and Bayesian inference methods, aiming to provide new horizons and genomics data support for the phylogenetic research of the Aeromachini.
2. Materials and Methods