Biostratigraphic study of Late Miocene (Pannonian and Pontian) endemic molluscs from
east Hungarian part of the Pannonian Basin revealed the relative persistence of the
deep water association during the Late Pannonian and Pontian. Consequently, the earlier
interpretation of these forms as Pontian or Lower Pontian ones, and definition of
the Early and Late Pontian substages by them, should be revised. The occurrences of
the sublittoral association can be divided into two stratigraphic units. In the littoral
facies zone 3 stratigraphic units were identified. Evolution from L. decorum to Prosodacnomya
took place between 7.7 and 7.0 million years, according to magnetostratigraphic and
seismic data. Basinward progradation is demonstrated by the geographic distribution
of molluscs. -from Author
