Comparative Analysis of Mitogenomes among Five Species of Filchnerella (Orthoptera: Acridoidea: Pamphagidae) and Their Phylogenetic and Taxonomic Implications

Simple Summary Filchnerella belongs to Insecta, Orthoptera and Pamphagidae, of which there are 19 recorded species. The wings of Filchnerella are diverse, including three grasshopper wing types: longipennate, short wings and small wings. The previous studies of Filchnerella are more about the description of species morphology, and few about exploring the phylogenetic relationships with limited number of species and DNA fragments, which are insufficient to study the phylogeny of the entire genus, especially in order to understand the evolution of wing types in Filchnerella. To better understand the mitogenomic characteristics of Filchnerella and reveal its internal phylogenetic relationships, the complete mitochondrial genomes of Filchnerella sunanensis, Filchnerella amplivertica, Filchnerella dingxiensis, Filchnerella pamphagoides and Filchnerella nigritibia were sequenced and comparatively analyzed in this study. The mitogenomes of these five Filchnerella species were found to be highly conserved. Phylogenetic analyses, based on mitogenome data of 16 species of Pamphagidae, using both the maximum likelihood (ML) and Bayesian inference (BI) methods, supported the monophyly of Filchnerella and produced valuable data for the phylogenetic study of the genus. Mitogenomes have been widely used for exploring phylogenetic analysis and taxonomic diagnosis. In this study, the complete mitogenomes of five species of Filchnerella were sequenced, annotated and analyzed. Then, combined with other seven mitogenomes of Filchnerella and four of Pamphagidae, the phylogenetic relationships were reconstructed by maximum likelihood (ML) and Bayesian (BI) methods based on PCGs+rRNAs. The sizes of the five complete mitogenomes are Filchnerella sunanensis 15,656 bp, Filchnerella amplivertica 15,657 bp, Filchnerella nigritibia 15,661 bp, Filchnerella pamphagoides 15,661 bp and Filchnerella dingxiensis 15,666 bp. The nucleotide composition of mitogenomes is biased toward A+T. All tRNAs could be folded into the typical clover-leaf structure, except that tRNA Ser (AGN) lacked a dihydrouridine (DHU) arm. The phylogenetic relationships of Filchnerella species based on mitogenome data revealed a general pattern of wing evolution from long wing to increasingly shortened wing.