L. Hably szerk.: Studia Botanica Hungarica 21. 1989 (Budapest, 1989)

Mészáros, Sándor: Comparison and relations of the Hungarian and the Mongolian flora

lb get a better impression on the actual connection of Mongolian and Hungarian species, the migration of Continental floristical Elements, the last part of this paper is devoted to the floristic history of the Crépis species in both countries. The genus Crepis was chosen because we have an up-to-date monography on the subject (BABCOCK 1947), and the author placed the origin of the genus to the region of the Altai-Tiensan Mts., the number of recent species present in the two countries are equal (11-11 species), and the ratio of the species common in both countries (2 species, 18.2%) is fairly near to that of all common species (17.3%), therefore this genus can be considered justly as representative. CONNECTION OF THE SPECIES OF THE GENUS CREPIS According to BABCOCK (1947), the genus Crepis possibly originated from the genus Dubyaea by the middle of the Tertiary period [at the earliest, in the Late Oligocène, at the latest, the Early Miocene*]. This latter genus is currently not represented in Mongolia, but there are 3 species of the genus Youngia known there which is closely related to Crepis. On the basis of a thorough morphological, genetical and cytological study, BABCOCK classified the sections and the species into three groups within the genus: group I. ancient, perennial species (with rhysome), group II. fairly primitive species, bulk of them perennial, group III. more evolved species, bulk of them annual or biannual ones. About half of the recent 11 species of Crepis belong to group I, the rest to group II (one species, namely C. czuensis Serg. is missing from the monography), that is, youngest species representing group III cannot be found there at all. In Hungary, representatives of all the three groups can be found but mostly those of group III (see Table 3). From the gene centre of the Altai-Tiensan region, the species of Crepis migrated towards four directions: - towards the West, to Europe - towards the South-West, to the Mediterranean and Africa - towards the North-East, to Northern America - towards the South-East, to tropical regions of Asia. Among the species belonging to the ancient group I, Crepis sibirica, C. pahidosa, C. mollis and C. praemorsa did reach, during their route towards the West, Northern Europe** during the Miocene as yet, when the southern part of the of the Ural Mts. and the more elevated parts of the recent Kirgizian steppe were emerging from the Ob-sea and, migrating from there towards the South reached our territories somewhen during the Pliocene or the Pleistocene. Among these four species, the C. mollis is already extinct from Hungary, and C. sibirica reached as far as the Carpathes only. Among these four species, we find the species C. sibirica and C. praemorsa currently living in Mongolia. From the other species in group I, C. multicaulis reached only as far as Scandinavia (where, as a nunatak species, it survived the Ice Age), while C. polytrichia and C. chrysantha remained as species with Central and Eastern Asian distribution (that is, we can witness essential differences in the adaptation capacities and agressrvity of the species). *Most of the species originated, however, during the Pliocene and the Pleistocenea lready. * *A fossil fruit of C. mollis was found in Great Britain from Upper Pliocene beds