Amu Darya
The Amu Darya sturgeon once occurred throughout the Amu Darya river basin, including its delta in the Aral Sea, but today it is restricted to the middle Amu Darya River (between Chardzhou and Kerki) and the Vakhsh River (an Amu Darya tributary). It has declined because of habitat loss, pollution and poaching, and is rated as critically endangered by the IUCN. Despite its threatened status, strong decline and range contraction, it can be locally fairly common and overall it is the least rare species of "Pseudoscaphirhynchus" ("P. fedtschenkoi" is possibly extinct and "P. hermanni" only survives in very small numbers).