关键词: 鞘翅目, 象甲科, 枣食芽象甲, 近缘种, 线粒体基因组, 蛋白质编码基因, 系统发育

Abstract: 【Aim】 To explore the phylogenetic relationship between Scythropus yasumatsui and related species at the mitochondrial genome level. 【Methods】 Using Illumina MiSeq platform, the mitochondrial genome of S. yasumatsui was sequenced, and the genome sequences were assembled, annotated and characterized. Based on the nucleotide sequences of 13 protein-coding genes in the mitochondrial genome, the Bayesian and ML phylogenetic trees of 13 species of the family Curculionidae were constructed. 【Results】 The results showed that the sequence length of the mitochondrial genome of S. yasumatsui is 16 472 bp (GenBank accession no.: MF807224), including 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes and 2 non-coding regions, and the order of genes is consistent with that of the ancestral insect mitochondrial genes. All of the 13 PCGs use ATN as the start codon, and except that cob and nad1 use TAG as the termination codon, other 11 PCGs use TA(A) as the termination codon. All of the 22 tRNA genes were predicted to contain typical cloverleaf secondary structures except the gene trnS1 lacking DHU arm and changing anticodon from GCT to TCT. Phylogenetic tree based on the nucleotide sequences of 13 PCGs showed that the phylogenetic relationship among eight subfamilies of the family Curculionidae was: (((Cryptorhynchinae+(Curculioninae+Molytinae))+Platypodinae)+(Entiminae+Cyclominae))+Dryophthorinae+Scolytinae). 【Conclusion】 The phylogenetic tree based on the mitochondrial genome showed that among the 13 species of the family Curculionidae, S. yasumatsui and Naupactus xanthographus belonging to the subfamily Entiminae clustered together in the same branch of phylogenetic tree, and this result is consistent with that of traditional morphological classification.

Key words: Coloptera, Curculionidae, Scythropus yasumatsui; related species, mitochondrial genome, protein-coding gene, phylogeny