Dr. Fűköh Levente szerk.: Malakológiai Tájékoztató 12. (Eger, 1993.)

KROLOPP, E.-SÜMEGI, P.: Vertigo modesta (Say), Vertigo geyeri (Lindholm, 1925) and Vertigo genesii (Gredler, 1856) species in Pleistocene formations of Hungary

It is a boreoalpine species, with mostly Northern European distribution (Scandinavia, Finland, Lithuania, Latvia, Denmark, sporadically the NE part of Germany and it occurs also in the Alps and in the Northern Carpathians). Its isolated occurrences are recorded from Ireland, Poland and from the S part of Germany (Kerney, M. P. et al, 1983, Licharev, I. M.-Rammelmeyer, E. Sz. 1962, Pokryszko, B. M. 1986, Waiden, H. 1966). In the Alps it penetrates up to an altitude of 1750 m (Klemm, W. 1974). Vertigo geyeri is a frequently occuring hygrophilous species living in inundation areas rich in carbonates or in swampy-marshy areas. In the litearature it is recorded for the first time in the list of Pleistocene species (Krolopp, E. 1982-83) where it was put into on the basis of the collection material of the Hungarian Geological Institute. From the collections made by P. Sümegi it became known from several places from Upper Pleistocene sediments of the Great Hungarian Plain (Nyilas, I.-Sümegi, P. 1989, Sümegi, P. 1989, Sümegi, P. et al. 1991). During the revision of Vertigo material it became clear that this was one of the characteristic fauna elements of sediments deposited in the Great Hungarian Plain in a humid environment, inundationa areas of high carbonate content (infusion loess). It is rare in typial eolian loesses. Up to the present Vertigo geyeri is known from 65 localities from Pleistocene sediments in Hungary (Krolopp, E.-Sümegi, P. 1992 b). The majority of the localities belongs to the Upper Pleistocene, 6 sites are recorded from the lower Pleistocene and only 2 ones from the Middle Pleistocene, respectively. The Pleistocene occurrences of the species are restricted almost exclusively to the Great Hungarian Plain and it was widespread especially in the Upper Würm and in the Late Glacial Phases. It had disappeared from our region presumably about 10-11 000 BP years ago. (Sümegi, P. 1991). Its mass occurrence was never recorded, it was found in the samples only as represented by a few specimens so far. Its accessory fauna contains mostly cold resistant hygrophilous species (Succinea oblonga, Cloumella edentula, Vertigo substriata, V. parcedentata, Trichia hispida). 3. Vertigo genesii (Gredler, 1856) Fig. l.e-f. Like the above-mentioned species, this one is also a boreoalpine species, living in Scandinavia, Finland, in te N part of Russia, at some spots in Poland and in some places of Germany and Switzerland (Kerney, M. P. et al, 1983, Licharev, I. M.-Rammelmeyer. E. SZ. 1962, Waiden, H. 1966). Recently it is reported from N. England as well (Coles, B-Colwille, B. 1980). According to the above-mentioned data the distribution of Vertigo genesii is similar to that of y geyeri, yet it seems that the latter has a distribution with its centre farther in the North than the previous one, besides, in the Alps it penetrates up to a higher altitude (that is till 2000 m), that the other species (Kerney, M. P. et al. 1983). This difference in the distribution of the two species can be attributed to their somewhat different ecology on the basis of which wo consider V. genesii to be a hygrophilous cold-demanding species while V. geyeri to be a cold- resistant hygrophilous one. A few occurrences of V. genesii were published for the first time by Sods (1955-1959), though part of them later proved to be belonging to V. geyeri. The first authentic specimen of the species was collected by Pál Sümegi from the Upper Pleistocene (Middle Würm) sediment near Jászfelsőszentgyörgy (Sümegi, P. 1991). V. genesii have two Lower Pleistocene and 16 Upper Pleistocene occurrences known so far from Pleistocene formations in Hungary. (Krolopp, E.-Sümegi, P. 1992 b) - See