The Phylogeny Of Genus Scylla And Population Genetic Structure Of Mud Crabs Along Coast Of China

Although the identification of Mud Crabs has been studied by a number of scientists, the phylogeny of Genus Scylla and population genetic structure of Mud Crabs along coast of China is still a problem need to be figured out. This paper mainly contains two parts of study: (1)Sequence Analysis of Mitochondrial 12S rRNA,16S rRNA and COI Gene of Mud Crabs along coast of China and the phylogeny of Genus Scylla; (2) Population genetic structure of S. paramamosain collected from the coast of the Southeastern China based on mtDNA COI sequences. Genetic distance and phylogenetic analysis suggested that the samples should be S. paramamosain.The NJ,BAYES and ML trees show that S. olivacea is far from the other three species and S. tranquebarica is closely related to S. paramamosain. A total of 130 crabs from 10 representative localities along the coast of Southeastern China were collected and anglicized at the mtDNA level in this study. By using a Mantel test, we found no significant correlation between pairwise population FST values (estimated by haplotypic frequencies) and geographic distances, suggesting that a simple model of isolation by distance is not appropriate for our data. Tests of neutral evolution (Tajima's D and Fu's Fs) revealed the D statistic was negative with a significant deviation from mutation-drift equilibrium, and result of Fu's Fs-test, which was devised specifically to detect population expansion is more sensitive to the presence of singletons in a sample, showed a highly significant value.