Despite the diversity and economic and ecological value of freshwater mussels, relatively little is known about their biology (especially for species outside of Europe and North America). Solenaiacarinata is an endangered freshwater mussel, is endemic to China and is now only distributed in Poyang Lake basin. However, its conservation status is not clear. Thus, for this study, surveys were conducted at 41 sites along the lower reaches of the Ganjiang River to study the conservation status of S.carinatus. The results showed that S.carinata had a restricted distribution and extremely low density. In addition, the habitat sediments where S.carinata was located were mainly composed of silt (particle size <0.0625 mm). RDA analysis showed that the density of S.carinata was correlated to dissolved oxygen, temperature, turbidity and chlorophyll-a. Microsatellite analysis showed that S.carinata had a low genetic diversity (mean HO: 0.419; mean HE: 0.484; mean PIC: 0.430). At the same time, we firstly report the glochidia of S.carinata and describe its morphological characteristic. Surprisingly, its reproduction period and morphological characteristics were different from that of others freshwater mussels. Therefore, this study clarified the resource conditions, endangered status and threat factors for S.carinata and it provided a theoretical basis for the conservation and management of its resources.