Former USSR and Asia: Endemic to the basin of Amu Dariya and Sir Dariya rivers (Ref. 35930). Considered endangered or extinct by authors (Ref. 6866). Registered in the International trade restricted (CITES II, since 1.4.98; CMS Appendix II); 1984 USSR Red Book; 1985 Turkmen SSR Red Data Book; 1996 IUCN Red List; and, 1997 CITES Lists (Ref. 35930).