Solenaia is a genus of freshwater mussels in the family Unionidae. They have a very elongated shell that lacks dentition.
There is only one recognized extant species:
There is also one species only known from the fossil record:
Many other species have been recognized before. Chinese literature sources have records of at least five different species.[1] However, recent taxonomic work has moved most former Solenaia species to other genera, including Sinosolenaia, Parvasolenaia, and Koreosolenaia.
The only extant species, Solenaia emarginata (synonym: Solenaia khwaenoiensis) is found in Thailand in Chao Phraya and Mae Klong drainages.