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

Vertigo modesta (Say), Vertigo geyeri (Lindholm, 1925) and Vertigo genesii (Gredler, 1856) species in Pleistocene formations of Hungary* E. Krolopp-P. Sümegi Abstract: As one of the results of a revision made on the Pleistocene Vertigo material of Hungarian Pleistocene formations this paper presents the survey of 3 species, so far umpublished or questionable. Vertigo modesta (Say) had come to light in 1992 from an Upper Würm loess in the Great Hungarian Plain. So far only one locality of it is known. Vertigo geyeri (Lindholm) is proved to be a characteristic fauna element of those sediments in the Great Hungarian Plain which had been deposited in a humid environment, in inundation areas of high carbonate content („infusion loess"). Vertigo genesii Gredler is a rare species, its separation from small specimens of Vertigo parcedentata (Braun) onthe basis of morphological criteria of the shell is uncertain, therefore it needs further investigations. During a revision of the Hungarian Pleistocene Vertigo material and of a study of the material of collections recently made (Krolopp, E.-Sümegi, P. 1992 a, 1992 b) we found three species which up to now have not been published from our Pleistocene formations or the correctness of data on them were questionable because of taxonomic problems. Since these species today do not occur in the territory of Hungary (Pintér, L. et al. 1979) their Pleistocene occurrence is important both from statigraphic and of paleoecological viewpoints. 1. Vertigo modesta (Say, 1824) Fig. 1. a-b. The species has a holarctic, circumpolar, in Europe arctic-alpine distribution (Kerney, M.P. et al., 1983, Waiden, H. 1966). Its occurence nearest to our region is in the Tátra Mts., where it lives at an altitude of 1900-2150 m (Lozek, V. 1964). In European literature it (recorded by the name Vertigo arctica) {Wallenberg, 1858); its identification with the American species described earler is more recent. The form V. tatrica, too described by Hazay presumably be longs to here. It is a hygrophilous species, living in shaded places in limestone mountains, in subarctic woodlands in Scandinavia, below rocks and broken plant fragments. It is recorded from European Quaternary format ons only from a few places (Lozek, V. 1964, Petrbok, J. 1959). From our Pleistocene it name to light up to now only one locality; from the loess outcrop of Öthalom which belongs to the town Szeged. It was found in 1991. Though the detailed investigation of the locality has not finished yet, it already seems to be certain, that this sequence of terrestrial loess had been formed in the Upper part of the Würm, between 25 and 16 000 years. V. modesta occurs in the lower level of the sequence. In its accessory fauna Pupilla triplicata, P. muscorum, Vallonia tenuilabris, V. costata are dominant. It needs further investigations to explain the occurrence of Vertigo modesta in the loess near Szeged. It is highly possible that during the Upper Pleistocene this species had a wider distribution in the Carpathians and along river valleys it had penetrated into the Great Hungarian Plain, too. At any rate it is noteworthy that at Szeged-Öfchalom several *A tanulmány az OTKA T 4259. sz. pályázat támogatásával készült