Complete mitochondrial genomes of five skippers (Lepidoptera: Hesperiidae) and phylogenetic reconstruction of Lepidoptera

摘要

We sequenced mitogenomes of five skippers (family Hesperiidae, Lepidoptera) to obtain further insight into the characteristics of butterfly mitogenomes and performed phylogenetic reconstruction using all available gene sequences (PCGs, rRNAs, and tRNAs) from 85 species (20 families in eight superfamilies). The general genomic features found in the butterflies also were found in the five skippers: a high A+T composition (79.3%-80.9%), dominant usage of TAA stop codon, similar skewness pattern in both strands, consistently length intergenic spacer sequence between tRNAGln and ND2 (64-87bp), conserved ATACTAA motif between tRNASer (UCN) and ND1, and characteristic features of the A+T-rich region (the ATAGA motif, varying length of poly-T stretch, and poly-A stretch). The start codon for COI was CGA in four skippers as typical, but Lobocla bifasciatus evidently possessed canonical ATG as start codon. All species had the ancestral arrangement tRNAAsn/tRNASer (AGN), instead of the rearrangement tRNASer (AGN)/tRNAAsn, found in another skipper species (Erynnis). Phylogenetic analyses using all available genes (PCGs, rRNAS, and tRNAs) yielded the consensus superfamilial relationships ((((((Bombycoidea+Noctuoidea+Geometroidea)+Pyraloidea)+Papilionoidea)+Tortricoidea)+Yponomeutoidea)+Hepialoidea), confirming the validity of Macroheterocera (Bombycoidea, Noctuoidea, and Geometroidea in this study) and its sister relationship to Pyraloidea. Within Rhopalocera (butterflies and skippers) the familial relationships (Papilionidae+(Hesperiidae+(Pieridae+((Lycaenidae+Riodinidae)+Nymphalidae)))) were strongly supported in all analyses (0.98-1 by BI and 96-100 by ML methods), rendering invalid the superfamily status for Hesperioidea. On the other hand, current mitogenome-based phylogeny did not find consistent superfamilial relationships among Noctuoidea, Geometroidea, and Bombycoidea and the familial relationships within Bombycoidea between analyses, requiring further taxon sampling in future studies.