Analysis of genetic differentiation and population structure of the Korean-peninsula-endemic genus, Semisulcospira, using mitochondrial markers

The genus Semisulcospira is an economically and ecologically valuable freshwater resource. Among the species, Semisulcospira coreana , Semisulcospira forticosta and Semisulcospira tegulata are endemic to the Korean peninsula and Semisulcospira gottschei is widespread in Asia. Therefore, maintenance and conservation of wild populations of these snails are important. We investigat-ed the genetic diversity and population structure of Semisulcospira based on the mitochondrial cytochrome c oxidase subunit I (COI), NADH dehydrogenase subunit 4 (ND4), and combined mitochondrial DNA (COI + ND4) sequences. All four species and various genetic makers showed a high level of haplotype diversity and a low level of nucleotide diversity. In addition, Fu’s F s and Tajima’s D neutrality tests were performed to assess the variation in size among populations. Neutrality tests of the four species yielded negative Fu’s F s and Tajima’s D values, except for populations with one haplotype. The minimum spanning network indicated a common haplotype for populations of S. coreana , S. tegulata and S. gottschei , whereas S. forticosta had a rare haplotype. Also, genetic differences and gene flows between populations were assessed by analysis of molecular variance and using the pairwise fixation index. Our findings provided insight into the degree of preservation of the species’ genetic diversity and could be utilized to enhance the management of endemic species.