| The mitochondrial DNA (mtDNA), which is typically a single circular duplex molecule with size ranging from approximately 15.4—16.3 kilobases, exists in almost all eukaryotic cells with highly copy numbers. Because of small size, compositional and nucleotide sequence conservation, maternal inheritance, and relatively rapid evolutionary rate, lack of intermolecular genetic recombination, excluding intron and intergenic spacer sequence, being easy to amplification and analysis, mtDNA has been extensively used for studying population structures and phylogenetic relationships at various taxonomic levels.We determined the complete mitochondrial DNA sequence of Arcyptera coreana (Insecta: Orthoptera: Arcypteridae) and compare it with the other two orthopteran species, Locusta migratoria and Gryllotalpa orientalis. The concatenated nucleotide sequences of the 13 protein-coding genes from 8 polyneoptera insects and an outgroup taxon was analyzed for reconstruction their phylogenetic relationship. From the study we obtained the following conclusion:1. Composition and gene order of A. coreana mitochondrial genomeA.coreana genome (15,783bp) contained the same 37 genes (two rRNAs, 22 tRNAs, and 13 proteins) plus the putative control region (894bp) as found in other arthropods, and share the identical gene order with Locusta migratoria. A total of 36 bp overlap regions among A.coreana mt genes are found in eight locations with size varied from 1-8 bp. A total of 114 bp of intergenic spacer sequence is spread over in 20 locations with size varied from 2-21 bp. The A+T-rich region known for the initiation of replication in vertebrates and invertebrates is located between the srRNA and tRNAIle genes, and contains the highest A+T content (86.0%) and spans 894 bp, which is shorter compared with that from other insects.2. Protein-coding genes and codon usageThe total number of codons in the A.coreana protein coding genes was 3718, excluding termination codons in each gene, the number is close to L.migratoria (3713). The A+T content of the 13 A.coreana protein-coding genes is 75.8 %, which is a little higher than that of L. migratoria (77.5%). Four genes (COII> ND5, ND4 和 ND1) have...
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