Trilobites from the Ludlow and Přídolí of England and Wales are described. A total of 15 families; 36 genera and 53 species are documented herein, including a new genus and seventeen new species; fourteen of which remain under open nomenclature. Most of the trilobites in the British late Silurian are restricted to the shelf, and predominantly occur in the Elton, Bringewood, Leintwardine, and Whitcliffe groups of Wales and the Welsh Borderland. The Elton to Whitcliffe groups represent a shallowing upwards sequence overall; each is characterised by a distinct lithofacies and fauna. The trilobites and brachiopods of the Coldwell Formation of the Lake District Basin are documented, and are comparable with faunas in the Swedish Colonus Shale and the Mottled Mudstones of North Wales. Ludlow trilobite associations, containing commonly co-occurring trilobite taxa, are defined for each palaeoenvironment. Trilobites in the British Přídolí are too rare and sporadic to systematize them into distinct associations. A preliminary study on the global diversity of Silurian trilobites is presented also. A total of six trilobite bioevents are recognised for the Silurian occurring in the argenteus-leptotheca, sedgwickii, centrifugus-murchisoni, nilssoni, formosus, and bouceki-transgrediens graptolite biozones, characterised by elevated extinction rates.
Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:566086 |
Date | January 2012 |
Creators | Storey, Andrew James |
Publisher | University of Birmingham |
Source Sets | Ethos UK |
Detected Language | English |
Type | Electronic Thesis or Dissertation |
Source | http://etheses.bham.ac.uk//id/eprint/3888/ |
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