The late Oligocene macroflora of Zsámbék, central Hungary

Abstract

Fossil plants were discovered by geologists in the dolomite quarry on Strázsa Hill, west of Zsámbék, central Hungary, during December, 2020. The analysis of the plant remains and subsequent field studies suggest that the fossil plants are preserved in sediments of the Mány Member of the Törökbálint Formation and the sandy-clayey layers overlying Mesozoic dolomites were formed during the Oligocene. The fossil plant assemblage includes a small number of taxa with a relatively high frequency of gymnosperms. Among the gymnosperms taxodiaceous twigs, assigned to ?Taxodium, are dominant. Angiosperms are represented by the family Lauraceae (Daphnogene and Laurophyllum), Betulaceae (cf. Alnus), Ulmaceae (cf. Ulmaceae gen. et sp.), and “Rhamnus” warthae, a taxon with unknown systematic relations and a putative endemic element of the Intra-Carpathian area of the Central Paratethyan region. The flora is dominated by gymnosperms and “Rhamnus” warthae, other taxa are present but at lower frequency. Although the plant fossils of Zsámbék represent wetland vegetation types, less suitable for climate reconstruction, the relatively high ratio of lauraceous elements suggests a frostfree, warm climate. The floristic composition of the Zsámbék flora is clearly comparable to other late Oligocene floras of Hungary, therefore earlier climate estimates based on other similar-aged floras may also be considered for Zsámbék.