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Eckart Håkansson, Institute of Geography and Geology (Denmark)
Marcin Machalski, Polish Academy of Sciences (Poland)
Claus Heinberg, Roskilde University (Denmark)
John W.M. Jagt, Natuurhistorisch Museum Maastricht (Netherlands)
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Rare finds of ammonites from the Cerithium Limestone in the basal part of the type Danian succession at Stevns Klint, Denmark have been reported ever since the exact boundary level was finally established by Rosenkrantz in 1924. In view of the generally accepted extinction of ammonites at the K-T boundary, these findings have routinely been interpreted to be remanié material.
Over the years more than fifteen ammonite specimens have been collected from the Cerithium Limestone all along Stevns Klint. Phragmocone infill of a number of these specimens from has been investigated without providing conclusive results as to whether they were reworked or rare survivors. However, recent investigations of the infill of one of the best-preserved specimens have now established positive evidence of actual survival, both on the basis of the general composition of the infill and of the presence of a calcareous dinocyst typical of the Danian at high latitudes (Machalski & Heinberg 2005). In consequence two species of ammonite, Baculites vertebralis and Hoploscaphites constrictus, therefore survived the K-T boundary event in the type Danian sea of the Danish Basin. In the last few years the presence of surviving ammonites has also been established in other parts of this basin, i.e. in the Maastricht area by J.W.M. Jagt. These findings are currently being written up
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