**4. Ice age refugia at the interface of windblown sand dunes and floodplains: examples from the Bátorliget marshland, Nyírség region, NE Hungary, and the Ócsa marshland, Danube-Tisza interfluve, Central Hungary**

The highly protected area of the Bátorliget marshland is situated on the NE part of the Great Hungarian Plain (GHP) approximately 2 km west of the state border with Romania in the area of the Nyírség alluvial fan covered by windblown sands (**Figure 1**). The Ócsa marshland is on the other located at the NW part of the GHP at the fringe of the Danube Lowland in an area of scattered windblown sand dunes. Both sites are located in an interdune depression hosting initially an oligotrophic lake during the ice age, which developed into a calcareous lake system finally evolving into a eutrophic lake then a marshland. According to the available absolute chronology, the emergence of an oligotrophic lake initiated around 20–22 ka during the coldest period of the last glacial: the last glacial maximum (LGM). However, the first mollusk remains turn up in deposits dated to the Late Glacial only. Shells of the Pontian *Pomatias rivulare*, the Central European woodland dweller *Discus perspectivus*, as well as the Boreal woodland dweller *Discus ruderatus*, presently populating the alpine woodlands of the Carpathian Mts, turn up as early as the transitional zone between the Late Glacial and the Postglacial in the profile of the Bátorliget marshland. This paleoassemblage composed of cold-loving and thermophilous elements can be clearly synchronized by the findings of pollen analysis indicating the presence of a mixed taiga hosting stands of pine and various temperate arboreal elements [55, 95]. These records thus indicate the development of a mixed taiga woodland at the interface of windblown sand and floodplain areas in the NE part of the GHP during the ice age, whose composition was the same as the mixed taiga woodlands of the foothill areas mentioned in the previous chapter. A significant difference in the mollusk faunas is the appearance of a Pontian gastropod taxon, which evolved during the Tertiary in the Carpathian Basin [96, 97], in the marshland sequence. This gastropod taxon, the *Pomatias rivulare*, has a clear preference for milder climatic conditions (**Figure 5**).

refugia for woodland mollusk taxa [49–55, 64]. These findings have been corroborated by later studies on the Quaternary mollusk fauna of the Hungarian Highland and the Western Carpathians [85–90]. It must be noted that in Ref. [90], radiocarbon results presented span the Holocene Epoch alone. Cold-loving and cold-resistant elements in the accessory fauna of the *Cochlodina cerata* horizon are represented by a single taxon, presently dwelling in beech and pine woodlands: *Discus ruderatus*. However, warmth-loving elements like *Bradybaena fruticum* and *Euomphalia strigella* have also been recorded in this part of the profiles. Consequently, the general composition of the mollusk fauna is clearly in line with the observations and conclusions made on the basis of charcoal remains. Namely, the presence of refugia for temperate thermophilous woodland taxa within a Late Glacial mixed taiga forest [45–52]. The Late Glacial presence of *Discus perspectivus* as well as the records of the mollusk taxa *Cochlodina cerata*, *Cochlodina laminata*, *Clausilia dubia*, *Clausilia pumila*, and *Laciniaria plicata* in the layers representing the Pleistocene/Holocene transition is a highly outstanding feature of the sites. The collective appearance of *Discus perspectivus* and *Discus ruderatus* indicates the development of a dual refugia in the study area [49], i.e., the collective presence of Pleistocene cold-resistant and cold-loving elements with warmth-loving

the Petény site, and B3 = local malacological zones of the sequence in the Petény site.

102 Biological Resources of Water

**Figure 4.** The radiocarbon-dated palaeoecological data from Petény (Peskő II) and Rejtek rock shelters A1 = anthracologicalbased vegetation phases of the sequence in the Rejtek site, A2 = mammalian phases of the sequence in the Rejtek site, A3 = local malacological zones of the sequence in the Rejtek site, A/B = archeological finds and times in the analyzed sites, B1 = anthracological- and pollen-based vegetation phases in the Petény site, B2 = mammalian phases of the sequence in

> A similar paleoassemblage was identified in the Postglacial/Holocene deposits of the Ócsa marshland. However, in this latter profile, the Pontian *Pomatias rivulare* is substituted by

*elegans* coevally with our Hungarian records was noted in the Early Mesolithic cultural layer of the Italian Grotta di Latronico Cave as well. Shells of this taxon have been retrieved in deposits older than 9000 cal BP years and those dated to the Postglacial and Early Holocene as well [101]. Representatives of this taxon with similar ages have been reported from Iberia [102] as well as Southern France [103]. In these latter examples, the first representative of the gastropod taxon *Pomatias elegans* likewise appears in layers older than the Mesolithic horizon

Ice Age Terrestrial and Freshwater Gastropod Refugia in the Carpathian Basin, Central Europe

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To sum up briefly, the mollusk fauna dated to the opening of the Holocene in the areas of the Ócsa and Bátorliget marshland was a woodland dweller one characterizing temperate closed woodlands. This Early Holocene fauna is marked by the appearance of such taxa, which are restricted to the areas of the Carpathians, the Transylvanian Mid-Mountains, and the Hungarian Mid-Mountains and unique to the Great Hungarian Plains, serving as outstanding indicator species in both the stratigraphy and the paleoenvironmental conditions because they tended to appear in the mildest interglacial periods enjoying the greatest rainfall during the Pleistocene [25, 26]. The exuberant woodland malacofauna is made up of highly tolerant species appearing in uniform quantities in the closed woodland environment, which inhabit the mountains of Central Europe and are widespread in the area extending from the Balkan Peninsula up to the Baltics. The most characteristic elements of this community are the following: the Carpathian-Baltic *Ruthenica filograna*, *Macrogastra latestriata*, and *Bulgarica cana*; the Carpathian *Perforatella vicina*; the Central European *Acicula polita*, *Laciniaria plicata*, and *Perforatella bidentata*; the Central and Southern European *Discus perspectivus* and *Oxychilus glaber*; the European *Carychium tridentatum*, *Vertigo pusilla*, *Ena obscura*, *Vitrea crystallina*, *Aegopinella pura*, and *Cochlodina laminata*; and the Euxinic *Pomatias rivulare* or Atlanto-

Both regions hosting the referred marshland had direct connections with the foothill areas of the surrounding mid-mountains, the south facing escarpments via the river valleys based on our subfossil distribution data of the mentioned woodland elements. It was these foothill areas which functioned as refugia for woodland elements from the Postglacial onward [55, 56].

**5. Ice age refugia of temperate forest steppe and steppe gastropods: The results of quaternary malacological investigations on the loess/ paleosol sequence of the Crvenka brickyard, northern Vojvodina,** 

The findings of Quaternary mollusk analyses implemented on radiocarbon-dated loess/paleosol sequences from the eastern half of the Carpathian Basin in the 1980s have clearly revealed that the Late Pleistocene environment of the Carpathian Basin was far from being uniform [54, 55, 64]. These observations gave an impetus to further comparative paleobiogeographical investigations using our malacological records deriving from different parts of the basin and covering the period of the Late Pleistocene. To highlight the environmental conditions characteristic of the southern part of the basin, our findings on the mollusk fauna of a Northern

dated at 9000 cal BP years.

Mediterranean *Pomatias elegans*.

**Serbia**

**Figure 5.** The European distribution of *Pomatias elegans* and *Pomatias rivulare* and their Hungarian fossil, pre-modern and modern occurrences. Horizontal black line = European distribution of *Pomatias elegans*; vertical black line = European distribution of *Pomatias rivulare*; white cross = Hungarian Pleistocene distribution of *Pomatias elegans*, Vértesszőlős, Tata, and Budai Várhegy; white stars = Hungarian modern distribution of *Pomatias elegans*, Bérbaltavár, Tihany, Őrtilos, Zákány, and Zákányfalu; white circle = Hungarian Holocene distribution of *Pomatias elegans*, Szurdokpüspöki, Esztergom, Budapest— Rákos-patak, Ócsa, Kiskörös, Fehérvárcsurgó, and Keszthely—Fenékpuszta, Kisapáti, Tapolca, Celldömölk, Ménfőcsanak, Balf, and Fertőboz; white pentagon = modern Hungarian distribution of *Pomatias rivulare*, Bátorligeti marshland, Szekszárd Sötét-valley, and Nagymányok; white rectangle = Hungarian Holocene and subrecent distribution of *Pomatias rivulare*, Bátorligeti marshland, Bátorliget Fényi-forest, and Vámospércs Jónás region.

its Atlanto-Mediterranean vicariant counterpart: *Pomatias elegans*. The radiocarbon-dated appearance of these latter taxa in the Ócsa profile is the oldest recorded one in Europe several thousand years before the first Atlantic distribution records of the taxon [98, 99]. On the basis of this record, the assumption that the Atlantic and Central European distribution of this taxon is connected to the Middle Holocene [100] must be refuted. The appearance of *Pomatias*  *elegans* coevally with our Hungarian records was noted in the Early Mesolithic cultural layer of the Italian Grotta di Latronico Cave as well. Shells of this taxon have been retrieved in deposits older than 9000 cal BP years and those dated to the Postglacial and Early Holocene as well [101]. Representatives of this taxon with similar ages have been reported from Iberia [102] as well as Southern France [103]. In these latter examples, the first representative of the gastropod taxon *Pomatias elegans* likewise appears in layers older than the Mesolithic horizon dated at 9000 cal BP years.

To sum up briefly, the mollusk fauna dated to the opening of the Holocene in the areas of the Ócsa and Bátorliget marshland was a woodland dweller one characterizing temperate closed woodlands. This Early Holocene fauna is marked by the appearance of such taxa, which are restricted to the areas of the Carpathians, the Transylvanian Mid-Mountains, and the Hungarian Mid-Mountains and unique to the Great Hungarian Plains, serving as outstanding indicator species in both the stratigraphy and the paleoenvironmental conditions because they tended to appear in the mildest interglacial periods enjoying the greatest rainfall during the Pleistocene [25, 26]. The exuberant woodland malacofauna is made up of highly tolerant species appearing in uniform quantities in the closed woodland environment, which inhabit the mountains of Central Europe and are widespread in the area extending from the Balkan Peninsula up to the Baltics. The most characteristic elements of this community are the following: the Carpathian-Baltic *Ruthenica filograna*, *Macrogastra latestriata*, and *Bulgarica cana*; the Carpathian *Perforatella vicina*; the Central European *Acicula polita*, *Laciniaria plicata*, and *Perforatella bidentata*; the Central and Southern European *Discus perspectivus* and *Oxychilus glaber*; the European *Carychium tridentatum*, *Vertigo pusilla*, *Ena obscura*, *Vitrea crystallina*, *Aegopinella pura*, and *Cochlodina laminata*; and the Euxinic *Pomatias rivulare* or Atlanto-Mediterranean *Pomatias elegans*.

Both regions hosting the referred marshland had direct connections with the foothill areas of the surrounding mid-mountains, the south facing escarpments via the river valleys based on our subfossil distribution data of the mentioned woodland elements. It was these foothill areas which functioned as refugia for woodland elements from the Postglacial onward [55, 56].
