Dear Volker,

I think, your objects are cores of mollusks Rzehakia (Oncophora), possible Rzehakia socialis (Rzehak). I have only fast found the Russian text, but with the quite a good paleontological plate with Oncophora. Look at Plate XVIII (Таблица XVIII) in the attached file. And see another attached paper for stratigraphical connection.

Best regards.

Tetiana

Dear Tetiana,

thank you very much for your fast and the first answer! I think, that you have solved my question very quickly, because Rzehakia partschi looks-  morphometric - very similar to my findings from "Altheim-Breitenlauh" and also have the right lithostratigraphic position (Base of "Grimmelfingen Beds"; Lower Miocene).

Thanks again and best regards;

Volker

Dear Volker, this is not Rzehakia, but very nice specimens of the bivalve Siliqua suevica (Mayer). See the attached description of this species in Schlickum (1970). Best wishes, Bettina

Dear Bettina,

... nice to hear from you! I think you are such an expert on invertebrates, fishes etc. from the Brackish Water Molasse of South Germany, that I have no doubt about your informations. But I will prove your determination (Siliqua suevica) tomorrow :-).

Another question to you Bettina: is this a common bivalve taxa within the "Grimmelfinger Beds" resp. the "Graupensandrinne" or is this taxa very rare to find there?

Thank you very much and all best wishes to Munich;

Volker