The Syr Darya sturgeon (Pseudoscaphirhynchus fedtschenkoi) is a species of fish in the Acipenseridae family. It is found in Kazakhstan, Tajikistan and Uzbekistan, where it is endemic to the Syr Darya River and, before its drainage, the Aral Sea. Due to the loss of its breeding site and damming projects over the length of the river, it is currently considered Critically Endangered and likely extinct, as no sightings have been reported since 1960.