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Journal of Micropalaeontology An open-access journal of The Micropalaeontological Society
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Volume 30, issue 1
J. Micropalaeontol., 30, 75–89, 2011
https://doi.org/10.1144/0262-821X10-021
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 4.0 License.
J. Micropalaeontol., 30, 75–89, 2011
https://doi.org/10.1144/0262-821X10-021
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 4.0 License.

  01 May 2011

01 May 2011

Early Permian glacio-marine thecamoebian assemblages from the northwest Himalayas, India

Arun Kumar1, Anjum Farooqui2, and Neerja Jha2 Arun Kumar et al.
  • 1Center for Petroleum and Minerals, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
  • 2Birbal Sahni Institute of Palaeobotany 53 University Road, Lucknow 226007, India

Keywords: Permian, glaciomarine, thecamoebians, Himalayas, India

Abstract. Diverse assemblages of thecamoebians are reported here from the Early Permian Manjir Formation of the northwest Himalaya in India. These thecamoebian tests were found in palynological preparations and are assigned an Early Permian age based on co-occurrence of age-diagnostic palynomorphs. Several of them show very close morphological affinity with extant thecamoebian genera, such as Amphitrema, Arcella, Centropyxis, Cyclopyxis, Cucurbitella, Difflugia and Trinema. This fauna lived in shallow-marine environments during the Early Permian deglacial phase of the widespread Late Carboniferous–Early Permian glaciation of Gondwana. The extant forms used for morphological comparison with the fossil forms were recorded from lakes and ponds in various parts of India. This study supports the current hypothesis of minimal evolution in thecamoebian lineages through geological time, and this group of protists has survived through long geological time and several mass extinction events without any significant morphological change. Stratigraphical and palaeontological evidence indicates that this fauna lived in the shallow-marine environments along the northwestern margin of Indian Gondwana during the deglacial phase of Late Carboniferous–Early Permian glaciation.

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