The Samia cynthia ricini (Lepidoptera: Saturniidae) is a commercial silk-producing insect belonging to an insect family Saturniidae in Bombycoidea. The species that has presumably been originated in India, is distributed in India, China, and Japan. Unlikely domestic silkworm the prime host plant for the species is a castor-oil plant (Ricinus communis in Euphorbiaceae). Recently, the eri-silkworm also is reared in Korea and is expected to be utilized for a diverse purpose. In this report, we present the complete mitochondrial genome of the species with the emphasis of a few major characteristics. The 15,384-bp long S. cynthia ricini (Lepidoptera: Saturniidae) mitochondrial genome was amplified into three long overlapping fragments (from COI ~ ND4, ND5 ~ lrRNA, and lrRNA ~ COI) and subsequent several short fragments using the long fragments as temperate. The primers for both long and short fragments were designed solely for lepidopteran genomes, without any species-specific primers. As a usual the genome is composed of 37 genes: 13 protein-coding genes (PCGs), two rRNA genes, and 22 tRNA genes, and one large non-coding region termed the A+T-rich region. Arrangement of the genome is identical to those of other lepidopteran mitochondrial genome, but this differs from the common arrangement found in a diverse insect order, by the movement of tRNAMet to a position 5’- up stream of tRNAIle. Unlikely previous report on the start codon for COI gene in Lepidoptera S. cynthia ricini COI gene starts with typical ATT codon located between tRNATyr and the beginning region of COI gene. The 22 tRNAs that are interspersed throughout the mitogenome ranged in length from 62 to 71 bp. All tRNAs but tRNASer(AGN) were shown to be folded into the expected cloverleaf secondary structures. More detailed structural and phylogenetic analyses among Bombycidae and Saturniidae in connection with other families in the Bombycoidea will be performed soon

The complete nucleotide sequences of the mitochondrial genome (mitogenome) from the white-spotted flower chafer, Protaetia brevitarsis (Coleoptera: Cetoniidae) was determined. The 20,319-bp long circular genome is the longest among the completely sequenced arthropods. This extraordinary length of the genome stemmed from 5,654-bp long A+T-rich region composed of twenty-eight 117-bp tandem repeats, seven 82-bp tandem repeats, and each two 19-bp and 38-bp tandem repeats. The P. brevitarsis contains a typical gene complement, order, and arrangement identical to most common type found in insects. The P. brevitarsis COI gene does not have typical ATN codon. Thus, we also designated it as AAC (asparagine), which is found in the start context of all sequenced Polyphaga within Coleoptera. All tRNAs showed stable canonical clover-leaf structure of other mt tRNAs, except for tRNASer (AGN), DHU arm of which could not form stable stem-loop structure. The 5bp-long motif sequence (TAGTA) that has been suggested to be the possible binding site for the transcription termination peptide for the major-strand also was found betweent RNASer (UCN) and ND1, as have been detected in all sequenced coleopteran insects.

The 15,338-bp long complete mitochondrial genome (mitogenome) of the Japanese oak silkmoth, Antheraeayamamai (Lepidoptera: Saturniidae) was determined. This genome has a gene arrangement identical to those of all other sequenced lepidopteran insects, but differs from the most common type, as the result of the movement of tRNAMet to a position 5’-upstream of tRNAIle. No typical start codon of the A. yamamai COI gene is available. Instead, a tetranucleotide, TTAG, which is found at the beginning context of all sequenced lepidopteran insects was tentatively designated as the start codon for A. yamamai COI gene. Three of the 13 protein-coding genes (PCGs) harbor the incomplete termination codon, T or TA. All tRNAs formed stable stem-and-loop structures, with the exception of tRNASer(AGN), the DHU arm of which formed a simple loop as has been observed in many other metazoan mt tRNASer(AGN). The 334-bp long A+T-rich region is noteworthy in that it harbors tRNA-likestructures, as has also been seen in the A+T-rich regions of other insect mitogenomes. Phylogenetic analyses of the available species of Bombycoidea, Pyraloidea, and Tortricidea bolstered the current morphology-based hypothesis that Bombycoidea and Pyraloidea are monophyletic (Obtectomera). As has been previously suggested, Bombycidae (Bombyxmori and B.mandarina) and Saturniidae (A.yamamai and Caligula boisduvalii) formed a reciprocal monophyletic group.

In this study, we determined the complete mitochondrial genome of the jewel beetle, Chrysochroa fulgidissima (Coleoptera: Buprestidae), from four overlapping fragments. The 15,592-bp long C. fulgidissima mitogenome exhibits a gene arrangement and content identical to the most common type in insects. The start codon of the C. fulgidissima COI gene is unusual, in that no typical ATN codon is available. The 875-bp A+T-rich region is the shortest among the coleopteran mitogenomes that have thus far been sequenced in their entirety. The most unusual feature of the genome is the presence of three tRNA-like sequences within the A+T-rich region: two tRNALeu(UUR)-like sequences and one tRNAAsnlike sequence. These sequence stretches evidence the proper anticodon sequence and the potential to form secondary structures, but also harbor many mismatches in the stems. Phylogenetic analysis using a concatenation of 13 amino acid sequences of protein-coding genes among the available sequenced species of coleopteran superfamilies (Buprestoidea and Elateroidea belonging to the infraorder Elateriformnia, and Chrysomeloidea and Tenebrioroidea belonging to the infraorder Cucujoiformia) by Bayesian inference, maximum-parsimony analyses, and maximum-likelihood analysis unexpectedly revealed a lack of support for monophyletic Elateriformia.

The completely sequenced mitochondrial genome of the brown marmorated stink bug, Halyomorpha halys, is a circular molecule of 16,518 bp with a total A+T content of 76.4%. Nucleotide composition and codon usage of this genome are near the means observed in other 12 hemipteran mitochondrial genomes; however, the initiation codon for CO1 gene appears to be TTG, dissimilar to what has been seen in the 12 mitochondrial genomes. In this genome, the A+T rich region between srRNA and tRNAIle gene includes two extensive repeat regions, in which each region includes 4 and 12 tandem repeats of a 73 bp sequence, respectively. The gene content, order, and structure of the H. halys mitochondrial genome are consistent with that of Triatoma dimidiata, belong to the same suborder Heteroptera, but different from two suborders, Auchenorrhynca and Sternorrhyncha, including various gene rearrangements. Analyzing phylogenetic relationship and comparing gene order and content of the 13 hemipteran mitochondrial genomes of three suborders, Heteroptera, Auchenorrhynca, and Sternorrhyncha, supported the morphology-based current hypothesis that both Auchenorrhynca and Sternorrhyncha are a monophyletic group.