Isolation and characterization of polymorphic microsatellite loci from pale-edged stingray,Telatrygon zugei(Elasmobranchii,Dasyatidae)

INTRODUCTION Sharks,skates and rays originated 400 Ma,with a further radiation throughout every ocean,and play a vi­tal role in maintaining the balance of marine ecosys­tems as top predators(Weigmann 2016).There are more than 1000 species of sharks,skates,rays and chimae­ras in the world,244 of which are distributed in Chinese seas.That is,Chinese chondrichthyan fauna make up at least one-fifth of the world’s extant species.Recent habitat degradation and overexploitation have caused sharp declines in many populations of elasmobranchs(White 2007;Dulvy et al.2017).Environmental chang­es and loss of oceanic apex predators due to overfishing could affect the migration routes and distribution of ba­toids(rays),resulting in community restructuring in the coastal ecosystem(Yamaguchi et al.2005;Myers et al.2007).Despite the combination of known high biodi­versity and heavy exploitation of elasmobranchs in Chi­na,there is little reliable information on the population genetics of many shark and ray species.Consequent­ly,clarification of the population structure is crucial for conservation and management,especially for endan­gered elasmobranchs.