Morphologic and molecular diversity of the foraminiferal genus Globocassidulinain Admiralty Bay, King George Island

Abstract Four distinctive morphological types can be found among living Globocassidulina in surface sediments of Admiralty Bay (King George Island, South Shetland Islands). The molecular analysis of the SSU and ITS rDNA indicates that they are monospecific and belong to Globocassidulina biora , exce...

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Bibliographic Details
Published in:Antarctic Science
Main Authors: Majewski, Wojciech, Pawlowski, Jan
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 2010
Subjects:
Online Access:http://dx.doi.org/10.1017/s0954102010000106
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0954102010000106
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Summary:Abstract Four distinctive morphological types can be found among living Globocassidulina in surface sediments of Admiralty Bay (King George Island, South Shetland Islands). The molecular analysis of the SSU and ITS rDNA indicates that they are monospecific and belong to Globocassidulina biora , except for minute forms from deeper than 200 m water depth which probably represent G. subglobosa . The morphological types of G. biora that show doubled or branched apertures, varied test size and shape as well as colour of cytoplasm, represent populations at different stages of ontogenetic development. However, the variability among large G. biora from the same locations is difficult to comprehend. It seems probable that G. biora is the only recent, large, shallow water Globocassidulina represented throughout the Antarctica, while G. crassa is typical for the Magellan region.