Assessment of the genetic diversity of Chinese freshwater mussels and refuge areas in the Yangtze River floodplain

Abstract

Abstract Freshwater mussels are one of the most diverse and endangered faunas worldwide. Owing to the continuing global biodiversity loss, it is essential to identify and protect populations that are not severely affected by human disturbances and ensure that natural genetic diversity is not inevitably lost. The generation of baseline genetic diversity data will help guide species conservation and restoration plans in the Yangtze River Basin where freshwater mussels are facing multiple threats and where strong declines have been observed. The genetic diversity of freshwater mussels was assessed using 818 mtDNA cytochrome c oxidase subunit 1 (COI), 565 28S rRNA and 509 COI + 28S datasets, and refuge areas in the Yangtze River floodplain were predicted using a Maxent habitat suitability model. The results showed that the genetic diversity of Aculamprotula spp., Sinosolenaia carinata, Cuneopsis rufescens, Lamprotula cornuumlunae, Lanceolaria lanceolata, Ptychorhynchus pfisteri, Schistodesmus spp. and Sinohyriopsis cumingii was lower than that of other freshwater mussels, which indicated that the conservation status of these species should be prioritized. The habitat suitability modelling showed that Poyang Lake and Dongting Lake basins (lakes and tributary rivers connected to the Yangtze River mainstem) present the most suitable habitats for freshwater mussels, indicating that lateral hydrological connectivity may be the most important factor in maintaining the genetic diversity of Chinese freshwater mussels. Consequently, Poyang Lake and Dongting Lake basins should be established as protected areas. This study provides valuable information for the conservation and management of freshwater mussel biodiversity in the Yangtze River basin, which will not only help conserve this vulnerable group but will also provide wider benefits to freshwater ecosystems.