Rhipidopsis in the upper Permian of the Dead Sea region, Jordan – Another clade of Mesozoic gymnosperms in the Permian?

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In recent years, the upper Permian of the Dead Sea region (Jordan) has yielded a rich and varied flora. This flora is of special interest because: (1) it is one of the very few rich and diverse late Permian floras, (2) of its superb preservation with excellent cuticles which enable whole-plant reconstructions, (3) it consists of a mixture of elements from different floral provinces, i.e. Euramerica, Cathaysia and Gondwana, and (4) of the precocious occurrences of major plant clades so far only known from the Mesozoic. Funds are requested for fieldwork in two newly discovered, hardly exploited localities in the Umm Irna Formation and for studying this material. Rhipidopsis foliage is particularly common in these localities and found in close association with a peculiar type of fructification that is so far unknown. Rhipidopsis is commonly regarded as an early ginkgophyte. However, a first screening shows that the stomata are very different from those of ginkgophytes and that the associated fructification looks very Caytonia-like. The Caytoniales are a small Mesozoic group of seed-ferns that is often regarded as ancestral to the flowering plants. The aim of this small project is to collect new material in order to test the hypothesis that Rhipidopsis is of caytonialean affinity.