ARAL SEA OSTRACODA AS ENVIRONMENTAL INDICATORS

Fluctuations in the level and chemistry during its history have played a major part in shaping the floral and faunal communities of the Aral Sea. Of the eleven species of Ostracoda (Crustacea) known to have bee n living in the Aral Sea in 1960, only one survives today due to the a nthropogenically induced salinity increase of the past three decades. The origins of a mixed fresh- and brackish-water ostracod fauna are di scussed, and it is concluded that some of the major faunal elements mu st have reached the Aral Sea Basin during a past high water level phas e when connection existed with the Caspian Sea. The taxonomic position of key taxa is clarified, and the major elements of the pre-1960 Aral Sea ostracod fauna are illustrated from Holocene sequences.