Uniquely preserved specimen of a large heteromorph ammonite Diplomoceras maximum Olivero et Zinsmeister, 1989 from the Maastroichtian (Late Cretaceous) Lopez de bertodano Formation of Seymour Island, Antarctica. Top picture showing portion og the shell and infilling concretionary material. Parts of the shaft that were not filled with sediment are missing. Photo below shows the ammonites with reconstructed parts of the shaft made from plaster. Bottom illustration is a reconstructed drawing of the Diplomoceras maximum shell made by A. E. Oleinik. Notice the beginning of the living chamber of the ammonite, marked by black suture line also visible on the photographs of the specimen.