Wurstkammer specimens of the planktic foraminifer Neogloboquadrina pachyderma (sinistral): A new morphotype from the Arctic Ocean and the Weddell Sea

• Main Author: Hommers, Harald
• Other Authors: Hass, H. Christian, Kaminski, Michael A.
• Format: Book Part
• Language: English
• Published: Grzybowski Foundation 1997
• Subjects: Antarctic; Arctic; Arctic Ocean; Southern Ocean; The Antarctic; Weddell; Weddell Sea; Antarc*; Neogloboquadrina pachyderma
• Online Access: https://oceanrep.geomar.de/id/eprint/31044/; https://oceanrep.geomar.de/id/eprint/31044/1/Hommers1997.pdf

From two cores of the central Arctic Ocean and the Southern Ocean (Weddell Sea) a new morphotype of the planktic foraminifer Neogloboquadrina pachyderma (sinistral) (Ehrenberg) with "sausage" shaped final chambers (i.e. "Wurstkammer") is described. A comparison of these morphotypes in the two polar regions shows significant differences in shape and frequency during the last 70,000 years in the central Arctic Ocean and during the last 140,000 years in the Weddell Sea. In the central Arctic Ocean the frequency of wurstkammer specinlens call be correlated to that of the so-called kummerform specimens during the last 70,000 years; this correlation cannot be seen in a core from the Weddell Sea. The wurstkammer and kummerform specimens are interpreted as being end-members of a morphological progressional line. The abnormal chamber growth is probably an adaption to various environmental stress conditions found in the two polar regions during the last 70,000 in the Arctic and 140,000 years in the Antarctic, but the reasons for this abnormality are not yet fully understood.