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We determined the complete nucleotide sequence of the mitochondrial genome for the rabbitfish Siganus fuscescens (Perciformes, Siganidae). This mitochondrial genome, consisting of 16,491 base pairs (bp), included 13 protein-coding genes, 2 ribosomal RNAs, 22 transfer RNAs, and a noncoding control region similar those found in other vertebrates; the gene order was identical to that of typical vertebrates. Most of the genes of S. fuscescens were encoded on the H-strand, while the ND6 and eight tRNA (Gln, Ala, Asn, Cys, Tyr, Ser [UCN], Glu, and Pro) genes were encoded on the L-strand. The reading frames of ATPase 8 and 6 and those of ND4L and ND4 overlapped by ten and seven nucleotides, respectively. All mitochondrial protein-coding genes began with an ATG start codon, except for CO1, which started with GTG. Open reading frames of S. fuscescens ended with TAA (ND1, CO1, ATPase 8, ND4L, ND5 and ND6), and the remainder had incomplete stop codons, either TA (ATPase 6 and CO3) or T (ND2, CO2, ND3, ND4, and Cytb). The origin of L-strand replication in S. fuscescens was located in a cluster of five tRNA genes (WANCY) and was 34 nucleotides in length. A major noncoding region between the tRNA-Pro and tRNA-Phe genes (828 bp) was considered to be the control region (D-loop). Within this sequence, we identified a conserved sequence block characteristic of this region. The rabbitfish was grouped with Siganus canaliculatus in most parsimony analyses, which showed 100% bootstrap support for their divergence. These findings are useful for inferring phylogenetic relationships and identification within the suborder Acanthuroidei.

We obtained the complete mitochondrial genome of the Ussuri white-toothed shrew Crocidura lasiura (Insectivora, Soricidae) at 17 362 base pairs (bp) containing 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a non-coding control region. Its gene order is identical to that of other vertebrates. Several repeat elements were identified in the non-coding control region (D-loop). Phylogenetic tree using mt protein-coding gene sequences showed that C. lasiura was closely related to C. attenuata. The reports of mt genome sequences of Crocidura were not enough to study phylogenetic relationships in genome levels. However, this report may help us to understand the phylogenetic relationships and evolutionary history of Crocidura.

The taxonomic relationship between two Korean field mice species, Apodemus agrarius coreae and A. a. chejuensis, as well as their possible historic migration routes, was examined by molecular genetic analysis of the complete mitochondrial cytochrome b gene of 73 mice collected from the Korean Peninsula and Jeju Island. Our findings suggest that A. a. coreae and A. a. chejuensis populations expanded and dispersed rapidly. Bayesian and network analysis showed that A. a. chejuensis is a clearly distinct population, and that A. a. chejuensis originated from the ancestral lineage of A. a. coreae. Based on our data, we hypothesize that the A. a. coreae population originated from eastern China or elsewhere. After the last glacial epoch, the lineage isolated from A. a. coreae had adapted to the new environment of Jeju Island, and with the reproductive isolation caused by the geographic barrier, this lineage eventually became a distinct population.