Thirteen species, one subspecies and five varieties of the brachiopod genus Schizophoria have been studied from parts of the Devonian and Carboniferous of Western Europe. One Carboniferous species and the Devonian subspecies of S. pygmaea are new, and will be formally named in due course. All taxa are shown to be both externally and internally distinct. In the Devonian, Schizophoria is most abundant in the Middle Devonian of the Eifel region (Germany), and in the Lower to Upper Devonian of the Dinant basin (Belgium). In the Carboniferous, Schizophoria is most abundant in the Dinantian of the Dinant basin, and in the C-D zone reef facies of the British Isles. Species of Schizophoria from the Carboniferous are shown to be statistically distinct, when appropriate characters are selected. A detailed knowledge of morphology is necessary before accurate statistical work is undertaken. Insufficient material prevented similar work on Devonian species. Certain Carboniferous species are apparently restricted to particular areas of reef limestone, and more than one species can in some cases be collected from the same stratigraphical and geographical position. Most of the species are long ranging forms, except Schizophoria provulvaria (Maurer) and S. strigosa (Sowerby) of the Siegenian to Lower Emsian, S. vulvaria (Quenstedt), of the Lower Emsian to Lower Eifelian, and S. pygmaea Struve, of the Eifelian. Schizophoria pygmaea is a dwarf form occurring in two horizons within the Eifelian of the Eifel region. Schizophoria woodi Bond is restricted to the Visean. Phylogenetically the species were probably derived from two root stocks in the Lower Devonian, S. provulvaria and S.strigosa. An earlier ancestor is unknown. Four main lines are recognised in the Carboniferous. Lines of evolution are based externally on outline and ornament, and internally on muscle fields and the form of the brachiophore plates.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:703946 |
| Date | January 1965 |
| Creators | Pocock, Yvonne Patricia |
| Publisher | Royal Holloway, University of London |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://repository.royalholloway.ac.uk/items/93ee0a11-3938-4761-b0a6-a0f3b9e3fb51/1/ |
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