Institution: | aForschungsstelle für Paläobotanik, Geologisch-Paläontologisches Institut, Westfälische Wilhelms-Universität Münster, Hindenburgplatz 57, 48143 Münster, Germany bDepartment of Environmental and Applied Geology, The University of Amman, Amman 11942, Jordan cGeologisches-Paläontologisches Institut, Universität Hamburg, Bundesstrasse 55, 20146 Hamburg, Germany |
Abstract: | Three new species of Dicroidium, D. irnensis, D. jordanensis and D. robustum, are described from the Um Irna Formation (Upper Permian) of the Dead Sea region, Jordan. The plant remains are preserved as compressions with excellent cuticles. These are the earliest unequivocal records of Dicroidium, a genus that is typical for the Triassic of Gondwana. It is also the northernmost occurrence of this genus that apparently originated in the Permian in the palaeotropics. Middle and Late Permian floras from the Arabian Peninsula and adjacent regions show a remarkable mixture of elements from different floral provinces, i.e. Euramerica, Cathaysia and Gondwana. The climatic amelioration in the Early Triassic apparently enabled Dicroidium to migrate southward and eventually colonise the entire Gondwana region. Dicroidium is one of the very few megaplant genera not affected by the end-Permian biotic crisis, the largest Phanerozoic extinction event. |