Poloniproductus varians Biernat (1966) brachiopod fossil found in Holy Cross Mountains of Skaly, Poland. This fossil is from the Eifelian (Devonian) Period.
Learn more at this paper GENUS POLONIPRODUCTUS NOV. (BRACHIOPODA, DEVONIAN) by Gertruda Biernat and Stanislas S. Lazarev in Palaeontologica (1988) at this web link.