Abstract Detail



Fossil plants at the intersection of evo-devo and phylogeny: celebrating the contributions of Gar W. Rothwell to biodiversity and evolution

Dunn, Michael [1].

Gymnosperms of Exposure A, Oxroad Bay (Tournaisian) East Lothian, Scotland.

The Tournaisian flora from the classic Cliff Section of Oxroad Bay at East Lothian, Scotland was discovered in 1930 by Gordon and that discovery prompted a number of papers that solidified the section as an extremely important Mississippian flora. In 1984, Gar Rothwell, Richard Bateman, Andrew Scott and other collaborators began a reinvestigation of the section. The goals of the reinvestigation included interpreting the paleoecology of the site and an attempt to reconstruct whole plants from the organ-taxa in the flora. The paleoecological studies were quite successful; however, to date no whole plants have been fully reconstructed. Of the six plant bearing exposures at Oxroad Bay, Exposure A is arguably the most well studied, and this paper reports on the status of the gymnosperms from Exposure A. Currently, five or possibly six stems have been identified; Bilignea and Eristophyton are relatively large stems at up to 100mm in diameter with  pycnoxylic wood.  Tetrastichia, Buteoxylon and Triradioxylon are considerably smaller and produce manoxylic wood. Oxroadopteris is a single small enigmatic specimen. Several variations of the problematic petiole genus Lyginorachis are present, some of which are found in organic connection to  Bilignea, Eristophyton, Tetrastichia and Oxroadopteris. A single root taxon, Amyelon is found throughout Exposure A but is only reported in organic connection to Tetrastichia. Reproductive structures include the cupules Calathospermum and Pullaritheca, the pollen organs Telangium and Melissiotheca, and five ovules; Salpingostoma, Tantallosperma Hydrasperma, Stamnostoma, and Eosperma. However, none of the reproductive structures have yet been found in connection to any of the stems.


1 - Cameron University, Biological Sciences, 2800 Gore Blvd, Lawton, OK, 73505, United States

Keywords:
gymnosperm
Mississippian
Oxroad Bay
Tournaisian
Whole plant reconstruction.

Presentation Type: Colloquium Presentations
Number:
Abstract ID:152
Candidate for Awards:None


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