Application of DNA barcoding to mtDNA COⅠ genes in 12 dung beetle (Onthophagus) species
Author of the article:
Author's Workplace：
Key Words：DNA barcodes, Onthophagus, COⅠ gene, taxonomy
Abstract： The DNA sequences of 12 dung beetle species from the genus Onthophagus were compared using a molecular marker of the 3′end fragment（731 bp） of the mitochondrial DNA COⅠ gene. 213 variable sites and 167 parsimony information sites were identified. Base substitution mainly occurred on the third codon (64 times), accounting for 83.12% of all substitutions. Interspecific divergence spanned from 8.1% to 15.8%, with the exception of the genetic distance between O. fodiens and O. lenzi which was below 2%, and intraspecific variation varied from 0 to 02%. Haplotype diversity (Hd) and nucleotide diversity (Pi) were 0.944±0.030 and 0.10518± 0.0045, respectively. Two sliding windows analyses demonstrated that the frequency of variable sites for all sequences located within 240-290 bp and approximately 675 bp was high. NJ phylogenetic tree revealed that molecular clusters was consistent with the traditional taxonomy based on morphological characteristics. The outgroup lineages separate first from the phylogenetic tree. Interspecific specimens clustered in one branch with intraspecific specimens clustered according to species and that branch. These results indicate that COⅠgene barcoding can reliably identify species of the genus Onthophagus.