H. Bathó Edit – Kertész Róbert – Tolnay Gábor – Vadász István szerk.: Tisicum - A Jász-Nagykun-Szolnok Megyei Múzeumok Évkönyve 12. (2001)

Palaeophytogeography of the Carpathian Pannonian Region in the Lower Jurassic

ZOLTÁN CZIER PALAEOPHYTOGEOGRAPHY OF THE CARPATHIAN - PANNONIAN REGION IN THE LOWER JURASSIC Tárii Crisurilor Museum, Oradea, Románia MM ' ' Considering the régiónál palaeogeography, the lower Jurassic macrofiora localíties from the Carpathian • Pannonian region are in the warm and wet palaeoclimatic beit that is parallel with the northern margins of the Tethys (Fig. 1). The palaeogeographical position of the localíties indicates that this flóra belongs to the European province of the Indo-European palaeophytogeographic territory (Fig. 2). As not all species from the lower Jurassic of the Carpathian - Pannonian region are characteristic to what classically a European flóra means, a new palaeophytogeographic distribution pattern is proposed. The flóra from the European Province comprises two major groups: aboriginal species and allochtonous species. The aboriginal species may be of local distribution, régiónál distribution, European distribution, and of expansion. The allochtonous species may be of eastern origin, western origin, and of expansion. The aboriginal elements originate from the inside of the European palaeophytogeographic province, and accordingly confer the dominant European character of the flóra. Two drawings (Pl. 1) show the numerical and percentage distribution for these elements. The aboriginal species of local distribution are present in a single locality of the European province, or in several localíties of this province, however in the same geological-structural unit from a European country. Endemic species represent the majority in this group. The aboriginal species of régiónál distribution are present in several localíties of the European province, in several major geologicalstructural units from a European country. The aboriginal species of European distribution are species known from several localíties of the European province, in several major geological-structural units, on the territories of several European countries. The aboriginal species of expansion migrated subsequentiy from Europe towards other provinces and continents. The allochtonous elements originate from the outside of the European province, and migrated subsequentiy in Europe. Their regions of origin may be very diverse, other palaeophytogeographic provinces, or other continents. Two drawings (Pl. 2) show the numerical and percentage distributions of these species. The allochtonous species of eastern origin came in Europe from the Middle-Asiatic or from the East-Asiatic province. They do not migrated farther from here. The allochtonous species of western origin spread in the Carpathian - Pannonian area during the early Jurassic. They originate from the Triassic of North America, and do not migrated farther from Europe. The allochtonous species of expansion migrated in Europe from other provinces. However, they migrated farther from here. All the 155 macrofiora species from the lower Jurassic of the Carpathian • Pannonian region are assigned to these palaeophytogeographic units (Tab. 1). The numeric and percentage distribution of the species (Pl. 3), indicate a heterogeneous flóra of mixed origin, in that the aboriginal species dominate (three quarters from the totál number of species). However, mainly because of the neighbour Middle-Asiatic province, as well as of the large migration possibilities, the presence of the allochtonous species alsó is important (a quarter from the totál number of species). 25