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Materials and methods, age dating, spore descriptions, and discussion of trilete spore affinities are available as supporting material on Science Online.
P.S. is a National Fund for Scientific Research Research Associate. Saudi Aramco provided material for study and publication. Work was undertaken as part of the Commission Internationale de Microflora du Paléozoïque/Saudi Aramco joint project "Understanding the Palaeozoic palynology of Saudi Arabia."
