Brachiopods from the Silberberg Formation (Late Eocene to Early Oligocene) of Atzendorf, Central Germany

摘要

Six brachiopod species, i.e., Discradisca sp., Cryptopora sp., Pliothyrina sp. cf. P. grandis (Blumenbach, 1803), Terebratulina tenuistriata (Leymerie, 1846), Rhynchonellopsis nysti (Bosquet, 1862), and Orthothyris pectinoides (von Koenen, 1894), have been identified in the Late Eocene to Early Oligocene Silberberg Formation of Atzendorf, Central Germany. The species R. nysti and O. pectinoides dominate the studied assemblage. Rhynchonellopsis is here transferred from the family Cancellothyrididae to Chlidonophoridae because it has a loop without united crural processes. Orthothyris pectinoides has a brachial skeleton of chlidonophorid type, but its transverse band is incomplete. In species composition, the assemblage from Atzendorf differs from other Paleogene and Neogene European assemblages by the absence of megathyridids and dominance of chlidonophorids, indicating a relatively deep environment.