Bryozoans from the lower Silurian (Wenlock) Steinsfjorden Formation of Ringerike, southern Norway


Authors: Ernst A, Nakrem HA

Published in: Bulletin of Geosciences, volume 90, issue 1; pages: 65 - 87; Received 5 June 2014; Accepted in revised form 11 September 2014; Online 3 December 2014

Keywords: lower Silurian, Bryozoa, Norway, taxonomy,

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A stenolaemate bryozoan fauna from the lower Silurian (Wenlock) Steinsfjorden Formation of the Ringerike district, southern Norway contains 10 species (2 cystoporates, 6 trepostomes, and 2 cryptostomes). Six species are new: Heterotrypa ringerikensis sp. nov., Trematopora maculata sp. nov., Amplexopora crassiparietum sp. nov., A. evae sp. nov., Orthopora worsleyi sp. nov., and Mediaporina kiaeri sp. nov. One species is described in open nomenclature: Eridotrypella sp. Trepostome bryozoans dominate this assemblage, both by diversity and abundance. The bryozoans occur in carbonates associated with evaporite minerals and sedimentary structures indicating very shallow depositional settings.


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