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This study is the first to sequence the complete mitochondrial genome (mitogenome) of Perforatus perforatus Bruguière, 1789 (Balanomorpha: Balanidae). The 15,536-bp long P. perforatus mitogenome contained a typical set of animal mitochondrial genes, along with one control region. The P. perforatus mitogenome had an inverted gene block (trnP-ND4L-ND4-trnH-ND5-trnF) between trnS(gct) and trnT. This inverted gene block had been detected six species in three subfamilies of the Balanidae family (Balaninae, Acastinae and Megabalaninae), but our results show that it is also present in Concavinae, in which P. perforatus is included. The phylogenetic tree based on the concatenated sequences of the 13 protein-coding genes and two rRNA genes showed that P. perforatus is closely associated with Acasta sulcate and Balanus trigonus within Balanidae. [ABSTRACT FROM AUTHOR]

The pear pest, Cacopsylla jukyungi (Hemiptera: Psyllidae), is the most damaging insect to commercial pears in South Korea. An assessment of the population genetic characteristics of the species will raise the potential of effective control. In the present study, we developed eight microsatellite markers specific to C. jukyungi and genotyped 132 individuals collected from 11 localities throughout South Korea. Populations showed lower observed heterozygosity than expected heterozygosity and slightly or highly positive values of inbreeding coefficients, suggesting that C. jukyungi is subjected to inbreeding. A strong dependence on commercial pear trees throughout the whole life cycle, even during overwintering, and a nationwide targeting of the overwintered adults are likely contributors to such heterozygosity deficiency. On the other hand, population analyses consistently indicated strong gene flow among populations, implying the presence of persistent factors that have facilitated this process. The nationwide expansion of pear orchards and the replacement with a popular new cultivar during the last 50 years, which may have accompanied the spread of C. jukyungi-bearing pear grafts and scions, are likely causes of such facilitated dispersal. Thus, a management strategy against unintended anthropogenic dispersal of the pear psyllid will be required for better control of C. jukyungi. [ABSTRACT FROM AUTHOR]

We sequenced the complete mitochondrial (mt) genome of Camponotus atrox (Hymenoptera: Formicidae), which is only distributed in Korea. The genome was 16 540 bp in size and contained typical sets of genes (13 protein-coding genes, 22 tRNAs, and 2 rRNAs). The C. atrox A+T-rich region, at 1402 bp, was the longest of all sequenced ant genomes and was composed of an identical tandem repeat consisting of six 100-bp copies and one 96-bp copy. A total of 315 bp of intergenic spacer sequence was spread over 23 regions. An alignment of the spacer sequences in ants was largely feasible among congeneric species, and there was substantial sequence divergence, indicating their potential use as molecular markers for congeneric species. The A/T contents at the first and second codon positions of protein-coding genes (PCGs) were similar for ant species, including C. atrox (73.9% vs. 72.3%, on average). With increased taxon sampling among hymenopteran superfamilies, differences in the divergence rates (i.e., the non-synonymous substitution rates) between the suborders Symphyta and Apocrita were detected, consistent with previous results. The C. atrox mt genome had a unique gene arrangement, trnl-trnM-trnQ, at the A+T-rich region and ND2 junction (underline indicates inverted gene). This may have originated from a tandem duplication of trnM-trnl, resulting in trnM-trnl-trnM-trnl-trnQ, and the subsequent loss of the first trnM and second trnl, resulting in trnl-trnM-trnQ. Keywords: mitochondrial DNA, mitochondrial genome, Hymenoptera, ants, Camponotus atrox, gene rearrangement. Les auteurs ont sequence le genome mitochondrial (mt) entier du Camponotus atrox (Hymenoptera : Formicidae), une espece presente uniquement en Coree. Le genome compte 16 540 pb et l'ensemble typique de genes (13 codant pour des proteines, 22 pour des ARNt et 2 pour des ARNr). La region riche en A+T chez le C. atrox, a 1402 pb, est la plus longue parmi les genomes sequences chez les fourmis et elle est composee de repetitions identiques en tandem formees de six copies a 100 pb et d'une copie de 96 pb. Au total, 315 pb d'espaceurs intergeniques sont repartis dans 23 regions. Il etait possible d'aligner les sequences de ces espaceurs chez les fourmis congeneriques meme s'il y a une divergence nucleotidique considerable, une propriete qui suggere la possibilite d'employer ces sequences comme marqueurs moleculaires au sein de ces especes. Le contenu et A/T aux premiere et deuxieme positions des codons des genes codant pour des proteines (PCG) etait semblable chez les especes de fourmis, incluant le C. atrox (73,9 % vs 72,3 % en moyenne). Avec l'accroissement du nombre de taxons echantillonnes au sein des superfamilles d'hymenopteres, il a ete possible de detecter des differences dans les taux de divergence (i.e. le taux de substitutions non-synonymes) entre les sous-ordres Symphyta et Apocrita, conformement aux resultats rapportes anterieurement. Le genome mt chez le C. atrox presente un arrangement genique unique, trnl-trnM-trnQ, a la jonction des regions riche en A+T et ND2 (inversion genique soulignee). Ceci pourrait etre survenu suite a une duplication de trnM-trnl, pour produire un arrangement trnM-trnl-trnM-trnl-trnQ, suivie de la deletion du premier trnM et du second trnl, pour produire trnl-trnM-trnQ. [Traduit par la Redaction] Mots-cles : ADN mitochondrial, genome mitochondrial, Hymenoptera, Camponotus atrox, fourmis, rearrangement genique., Introduction Insect mitochondrial (mt) genome sequences have been compiled for more than 500 species covering all insect orders (Feijao et al. 2006). One of the most species-rich orders, Hymenoptera, is [...]