Unique Duplication of trnN in Odontoptilum angulatum (Lepidoptera: Pyrginae) and Phylogeny within Hesperiidae

SIMPLE SUMMARY: Pyrginae is one of the major groups of the Hesperiidae, and has some particular characteristics. The annotated complete mitogenome from this subfamily is reported here. The gene order of the new mitogenome with the duplication of trnN differs from the typical Lepidoptera-specific arrangement and is unique to Hesperiidae. The presence of a pseudo gene in the mt genome of Odontoptilum angulatum supports the duplication of trnN, following the TDRL model. Comparison of the newly generated mitogenome of Odontoptilum angulatum to all available mitochondrial genomes of other rearranged Pyrginae species revealed that the condition of Odontoptilum angulatum is of independent origin. Therefore, we hypothesize that the gene block trnN–trnS1–trnE is the hot spot of gene rearrangement in the Tagiadini of Pyrginae. Phylogenetic analyses based on 13 protein-coding genes and entire RNA genes of mitogenomes show the monophyly of Pyrginae. ABSTRACT: To explore the variation and relationship between gene rearrangement and phylogenetic effectiveness of mitogenomes among lineages of the diversification of the tribe Tagiadini in the subfamily Pyrginae, we sequenced the complete mitogenome of Odontoptilum angulatum. The genome is 15,361 bp with the typical 37 genes, a large AT-rich region and an additional trnN (trnN2), which is completely identical to trnN (sequence similarity: 100%). The gene order differs from the typical Lepidoptera-specific arrangement and is unique to Hesperiidae. The presence of a “pseudo-trnS1” in the non-coding region between trnN1 and trnN2 supports the hypothesis that the presence of an extra trnN can be explained by the tandem duplication-random loss (TDRL) model. Regarding the phylogenetic analyses, we found that the dataset comprising all 37 genes produced the highest node support, as well as a monophyly of Pyrginae, indicating that the inclusion of RNAs improves the phylogenetic signal. Relationships among the subfamilies in Hesperiidae were also in general agreement with the results of previous studies. The monophyly of Tagiadini is strongly supported. Our study provides a new orientation for application of compositional and mutational biases of mitogenomes in phylogenetic analysis of Tagiadini and even all Hesperiidae based on larger taxon sampling in the future.