Folia Historico-Naturalia Musei Matraensis - A Mátra Múzeum Természetrajzi Közleményei 16. (1991)

Fűköh, L.: Examinations on faunal-history of the Hungarian holocene Mollusc fauna (Characterization of the succession phase)

The most significant change of the faunal succession can be observed at the time of Boreal phase, the increase in number of species was 29,9 4. Its reason is, that the faunistic effect of climate changing passed off between the Pleistocene - Holocene periods can be perceptibled at that time, at first. Further increases in number of species were: the Atlantic 15,8 '-., the Sub-Boreal 2,8 H, the Sub-Atlantic 7,3 \. This form of faunal development made it possible that malacologists could improve dismembering of the Holocene Age by setting up malaco - zones with help of the appearance of new species in certain phases of this period (HORACEK - LOZEK 1988). Beside climate marker species have great importance of faunal examination results - like in case of dismembering of the Hungarian Holocene fauna - forming the basis of relative frequency values. As a result of these examinations we known the evolution of the Czech and Slovakian Holocene fauna. According to LOZEK (1982) the process of this evolutionary progress is the next: . According to LOZEK's opinion this phase in the richest in species. We can find the species of the previous group at that time, but the forest elements become core and more frequent, like Acicula poli ta

, Acanthinula aculeata

, Ena montana

, Ruthenica filograna

, Isognomostoma isognomostoma

, Orcula doliolum

, Euomphalia strigella

, Bradybaena fruticum

. This phase is the maximum of Vallonia costata . (It have to be mentioned here, that the faunal evolution divided into two phases by LQZEK is equal with the first succession phase of faunas of the Hungarian medium high mountain ranges). 3. This phase is can be characterized by partly the maximal development of forest associations partly forging ahead the fauna preferring open-area. The phase can be divided into two sub-phases. 3/a. The most characterizing attribute of the first sub-phase is the entière decrease of relative frequency of Vallonia costata

. Which is more this species disappears in certain cases. Other characteristic feature is the increasing of the frequency of Laciniaria biplicata

, and high percentage of Carychium tridentatum

. 3/b. This, sub-phase is the secondary appearance of open-area preferring species. The frequency of Chondrula tridens

, Granaria frumentum

, Truncatellina cylindrica

, Vallonia sp

. increases on limestone territories. This secondary steppe-formation is,in close connection with the people of Neolithic Age. These two sub-phases of LOZEK's third phase can be paralleled with the second succession period of the Atlantic, and with formation of the closed forest fauna, according to the ?;xaminations of the Hungarian medium high mountain ranges 4. The main events of this phase are the improverishment of the forest fauna and the development of fauna liable to anthropogeneous effects on the culture areas. The number of species preffering open areas increases in the natural associations (

Granaria frumentum

, Vallonia pulchslla

, Chondrina clienta

, Aegopinella minor

). Appeares firstly the Zebrina detrina then the Monacha cartusiana

, and the Helicella obvia in the culture areas. The stratigraphical ranging of the above mentioned faunal phases are next: first phase - Pre-Boreal and Boreal, second phase - Atlantic, third phase - Epi-Atlantic

, fourth phase - SubBoreal, Sub-Atlantic. The previously mentioned divergences must be solved by canceling L02E«'S Epi-Atlantic phase. Poland Similar faunal assemblages are mentioned from different territories of Poland by ALEXANOROWICZ) ALEXANDROWICZ - NADACHOWSKI - RYDLEWSKY - VALDE-NOVAK WOLOSZYN 1985). Characterizing the certain Holocene climatic periods he refers to his observation that the individual frequency of Vallonia costata is constant in the Early Holocene sediments. According to him this is equal with the Boreal phase

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