Matskási István (szerk.): A Magyar Természettudományi Múzeum évkönyve 90. (Budapest 1998)

Bajzáth, J.: Plant macrofossils from the Hungarian Pleistocene III. Palaeobotanical study of Győrújfalu, Western Hungary

Picea, Abies, Carpinus, Tsuga and Pinus were found to become dominant in the later part of the interglacial cycle (mesocratic C and oligocratic phase). The occurrence of Azolla filiculoides in great abundance is noteworthy. There are differences between the faunal and vegetational subdivision of the Pleistocene. The Győrújfalu locality is assigned to the Lower Pleistocene based on the vertebrate biostratigraphy, whereas it belongs to the Middle Pleistocene based on the vegetational history. However, the exact stratigraphical subdi vision of the Cromer interglacialcomplex has not yet been accomplished in Hungary hy the vegetational history. Therefore the vertebrate biostratigraphical results are applied to assess the age of the locality. Consequently, the Lower Pleistocene is used in the sense of vertebrate biostratigraphy in this publication. THE FLORA OF GYŐRÚJFALU The interglacial flora including the Characeae seems to be very similar to the younger interglacial (Holsteinian) and to the modern floras of the present temperate zone. (Table 1) However, some characteristic Tertiary relics or exotic elements (comprising 6% of the total flora) were also found in the assemblage (Salvinia natans, Azolla filiculoides, Picea ornoricoides, Ostrya carpinifola, Caldesia parnassifolia. Najas tenuissima, Carex paucifloraides, Ca rex elongatoides). Azolla filiculoides was considered a guide fossil of younger, Mindel-Riss or Holsteinian interglacial by previous palaeobotanical studies. According to European researchers (WILSON 1973, WEST 1980, LANG 1994), Azolla filiculoides and Najas tenuissima are characteristic of the Cromer interglacial complex in Europe. The occurrence of Salvinia natans together with Azolla filiculoides shows an interglacial stage in the Lower Pleistocene in Hungary (SiMONCSICS & SZÉLES 1979, MIHÁLTZNÉ-FARAGÓ 1982). These fossils indicate a eutrophic freshwater environment during the interglacial stage. Azolla is regarded as an extinct species from the modern European floras. The present distribution of this species is restricted to the western subtropical region of North America. Najas tenuissima and Salvinia natans exist in Europe today although in a very restricted area. Caldesia parnassifolia is a unique Mediterranean element in the modern Hungarian flora. It is a relic species from the warm periods. Picea ornoricoides, Carex paucifloroides and Carex elongatoides are now extinct but they were characteristic elements of the interglacial floras in Europe, Belarus and Russia until the Riss (Saalian) glacial. They are probably closely related to the modern Picea omorica, Carex pauciflora and Carex elongata. Macroremains of real terrestrial elements of angiospermatophyta, trees and shrubs are absent or underrepresented in the macrofossil assemblage such as Carpinus betulus and Ostrya carpinifolia. Considering the ecological requirements of these plants, almost all of them are aquatic or mire (telmatic) herbaceous species. The presence of conifers both in the macrofossil and in the pollen assemblage is significant. This shows a borealtype of woodland, while a relatively great number of termophylus taxa are present among the aquatic and mire assemblage. In addition, the association of severe! herbaceous