THE GENETIC DIVERSITY OF THE 16S rRNA GENE IN THE MITOCHONDRIAL DNA OF THREE WILD POPULATIONS OF EXOPALAEMON CARINICAUDA
脊尾白虾(Exopalaemon carinicauda)3个野生群体mtDNA 16S rRNA序列差异及长臂虾科系统进化关系

Using PCR amplification and sequencing analysis, we examined the 16S rRNA gene in the mitochondrial gene of total 58 individuals that belonged to three wild populations of Exopalaemon carinicauda, which were sampled in the Haizhou, the Xiangshan, and the Laizhou Bays. 16S rRNA fragments that had 509bp were obtained in our study. Through comparing the variation sites, nucleotide diversity and average number of nucleotide differences were calculated to analyze the gene sequence variation and genetic diversity. The results showed that the colonies from the Haizhou and the Laizhou Bays had lower levels of genetic diversity than that from the Xiangshan Bay. Fst values between the Xiangshan and the Laizhou Bays showed significant genetic differences, and Fst values among all the other populations showed no strong genetic differences. The molecular phylogenetic tree was constructed using the NJ method to study molecular phylogeny of several species of Palaemonidae. Our finding indicated that the Phylogenetic tree clustered into two branches: Palaemoninae clustered into one branch, and Pontoniinae clustered into the other. In addition, differentiation time of 12 species of the Palaemonidae was deduced base on the percentage of the 16S rRNA divergence.