Late miocene brackish-water mollusks and the history of the Aegean basin

Brackish-water mollusks are studied from several sections in northern Greec e (Macedonia, the Serres basin) and the Aegina Island. Six of the 22 specie s of bivalve mollusks and one subgenus of cardiids are identified as new ta xa: Cerastoderma macedonicum, Lymnocardium (Euxinicardium) prominens, L. (E .) serresense, L. (Hellenicardium) hellenicum subgen. et sp. nov., L. (H.) strimonense, and Pseudocatillus submedius. Ten species and almost all gener a and subgenera (except Cerastoderma, L. (Hellenicardium), and Mactra) are identical to the Pontian taxa of the Eastern Paratethys. Three species, one subspecies and all genera and subgenera (except the new taxa) were reporte d from the Messinian of Italy and Spain. In the Serres basin, deposits of t he underlying Dafni Formation enclose abundant assemblages of marine mollus ks, while the overlying sediments contain the marine microfauna and oysters . According to mollusks, the brackish-water deposits of the section stand i n direct correlation with Pontian strata the Paratethys, at least with a pa rt of them, on the one hand, and probably corresponds to the upper Messinia n of the Mediterranean, on the other. According to the paleogeographic data , the Aegean basin was not a gulf of the Paratethys, but either a part of t he Messinian basin, or an intermediate basin, where the Pontian fauna was f ormed.