Genetic Studies On The Roughskin Soulpin Trachidermus Fasciatus In Weihai Based On MtDNA

The Roughskin soulpin(Trachidermus fasciatus Heckel) is a rare fish that lives in warm temperate zones in East Asia.It is a small species with a bottom-dwelling habit.The Roughskin soulpin is only found in China,Korea and Japan.In Korea,it is found on the northwestern coast of the Korean peninsula.In Japan,the Roughskin soulpin is found only in Ariake Sound and Isahaya Bay along with the rivers pouring into them.In China,the species distribute along the eastern coast,in the Bohai Sea,the Yellow Sea and the East China Sea,as well as in the rivers that pour into them.Its main areas of distribution are in seven provinces and two municipalities.The seven provinces are Liaoning,Hebei,Shandong,Jiangsu, Zhejiang,Fujian and Taiwan.The two municipalities are Shanghai and Tianjin.Historically,the Roughskin soulpin has distributed widely in the East Asia area. In China,it is found mostly in the southeast coastal waters and the rivers pouring into these areas.Recently,owing to a combination of natural and human activities,its population in the wild has gradually declined to the point where it is now considered to be an endangered species.During the past several decades,the economy in the same areas has experienced a period of rapid development.Due to this rapid economic development and the pollution of aquatic habitats,the survival of the Roughskin soulpin is increasingly threatened.Furthermore,the traditional migratory routes have been seriously blocked because of the considerable barriers appeared in the upper reaches and the construction in the river.As a result,the Roughskin soulpin is almost extinct in their original habitats,especially in Songjiang.So it has been listed in the Second Order of Protected Animals in China.The critical importance for the effective conservation and management is to understand the population genetic status,because it is the basic of the survival and prosperity for a species.However,in previous work,the research is mainly focused on the environmental factors' effect on the growth,reproducibility,annual cycle of GSI, embryonic developmenf,chromosome analysis,annual cycle of thyroid gland, histological analysis of the digestive organ,but rarely on conservation genetics based on molecular analysis.Therefore,in the present study,the genetic diversity based on mtDNA control region sequence is used to investigate the genetic status of the population.It is anticipated that the basic genetic data of mtDNA sequence could also be valuable for the future conservation and management to maintain the species as sustainable resources while ensuring that they remain as functional elements of their ecosystem.The termination associated sequence domain(TAS),the central conserved domain(CD) and the conserved sequence block domain(CSB),were identified in the mtDNA control region of Roughskin soulpin.Three conserved blocks(CSB-F,CSB-E,CSB-D) in the CD domain and three conserved sequence blocks(CSB1,CSB2,CSB3) in the CSB domain were identified as well.Sequence data are obtained from 54 Roughskin soulpins in the coastal waters of Weihai,describing 25 haplotypes.The haplotype and nucleotide diversity is 0.997 +/-0.012 and 0.01324 +/-0.00084,respectively,showing a high level of genetic diversity in this species.The possible reason could be that the local people in Weihai have not realized the value of the Roughskin soulpin,and there is no demands in the market.Since the Roughskin soulpin is facing with serious threat widely in China,the Roughskin soulpin in Weihai undoubtedly becomes a precious resource.So we should play great importance on its conservation and sustainability to prevent the loss of the genetic diversity.