Complete mitochondrial genome of Palpita hypohomalia (Lepidoptera: Pyraloidea: Crambidae) and its phylogenetic implications

The complete mitochondrial genome of a pyraloid species, Palpita hypohomalia, was sequenced and analyzed. This mitochondrial genome is circular, 15,280 bp long, and includes 37 typical metazoan mitochondrial genes (13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes) and an A+T-rich region. Nucleotide composition is highly biased toward A+T nucleotides (81.6%). All 13 protein-coding genes (PCGs) initiate with the canonical start codon ATN, except for cox/ which is CGA. The typical stop codon TAA occurs in most PCGs, while nad2 and cox2 show TAG and an incomplete termination codon T, respectively. All tRNAs have a typical clover-leaf structure, except for trnS1 (AGN) which lacks the dihydrouridine (DHU) arm. Comparative mitochondrial genome analysis showed that the motif "ATGATAA" between atp8 and atp6, and the motif "ATACTAA" between tmS2 and nad1 were commonly present in lepidopteran mitogenomes. Furthermore, the "ATAG" and subsequent poly-T structure, and the A-rich 3' end were conserved in the A+T-rich regions of lepidopteran mitogenomes. Phylogenetic analyses based on our dataset of 37 mitochondrial genes yielded identical topology for the Pyraloidea, and is generally identical with that recovered by a previous study based on multiple nuclear genes. In a previous study of the Crambidae, the Evergestinae was synonymized with Glaphyriinae; the present study is the first to clarify their close relationship with mitogenome data.