The evolution and distribution of normapolles pollen during the cenophytic

Abstract

Long-term palaeopalynological studies of the Upper Cretaceous freshwater and marine sediments of the Bohemian Massif and of other European areas have yielded the following results. The first recorded Normapolles pollen are of middle Cenomanian Age and are associated with the first triporate forms; thus, the Normapolles did not necessarily arise from the triporates. Changes in both the vegetation and pollen morphology that occurred at this time were in response to changing palaeoecological, palaeogeographical and palaeoclimatological conditions. The discovery of Normapolles on the Indian subcontinent changes the hitherto maintained views on the phytogeographic distribution of the Normapolles, and suggests that their geographic occurrences might be significant with respect to plate tectonic reconstructions. In Europe there are differences between the Upper Cretaceous palynospectra of the Mediterranean and boreal areas, with the Upper Cretaceous sediments of the South Bohemian basins representing a transitional flora. The progressive evolution of the Normapolles group has provided a basis for the biostratigraphic subdivision of the Upper Cretaceous. Without the Normapolles we would have no idea of the explosive evolution of flowering plants during this period.