International audienceMore than one thousand specimens of a morphological complex including Galeacysta etrusca Corradini & Biffi 1988 from 11 Upper Miocene and Lower Pliocene localities of the Paratethyan and Mediterranean realms have been studied using a biometric approach in part relating to the degree of separation between endocyst and ectocyst. Four stable biometric groups have been distinguished statistically, the occurrence or prevalence of which appears closely linked to environmental conditions irrespective of the realm. Group ‘a' is related to brackish conditions, group ‘b' to marine conditions, group ‘c' to freshwater, and group ‘d' to high nutrient levels. Based on an accurate chronology provided by calcareous nannoplankton bioevents and recognition of the Messinian Erosional Surface, this study reveals: 1. the high sensitivity of the Galeacysta etrusca complex for reconstructing paleoenvironments and discriminating phases of connection and isolation of basins; 2. the detailed history of this species complex which originated in the Pannonian Basin at ca. 8 Ma before invading the Dacic Basin during the interval 6–5.60 Ma, then migrating into the Mediterranean during high sea-level connections (the ‘Lago Mare' events just before and after the peak of the Messinian Salinity Crisis, i.e. at 5.60 Ma and during the interval ca. 5.46–5.278 Ma, respectively), and finally into the Black Sea at ca. 5.13 Ma; 3. an improved paleogeography for the Mediterranean and Paratethyan realms with focus on the location of corridors and the timing of when they were active. Based on field observations and dinoflagellate cyst data, we propose that the reflooding of the Mediterranean Basin by Atlantic waters occurred at ca. 5.46 Ma, about 130 kyr before the Zanclean GSSP (5.332 Ma)

Life and depositional environments in the sublittoral zone of Lake Pannon, a large, brackish Paratethyan lake from the Late Miocene, were reconstructed from fossils and facies of the Szák Formation. This formation is exposed in several, roughly coeval (9.4-8.9 Ma) outcrops, located along strike of the paleo-shelf-break in northwestern Hungary. The silty argillaceous marl of the formation was deposited below storm wave base, at 20-30 to 80-90 m water depth. The abundance of benthic organisms indicates that the bottom water was usually well oxygenated. Interstitial dysoxia, however, may have occurred immediately below the sediment-water interface, as evidenced by occasional preservation of trace fossils such as Diplocraterion. The fauna comprised endemic mollusks, including brackish cockles of the subfamily Lymnocardiinae, dreissenid mussels (Congeria), and highly adapted, uniquely large-sized deep-water pulmonate snails (planorbids and lymnaeids). Ostracods were dominated by endemic species and, in some cases, endemic genera of candonids, leptocytherids, cypridids, and loxoconchids. Fish remnants include a sciaenid otolith and the oldest skeletal occurrence of Perca in Europe. The phytoplankton comprised exclusively endemic coccolithophorids, mostly endemic dinoflagellates (prevailingly Spiniferites), and cosmopolitan green algae. The Late Miocene fauna and flora of Lake Pannon were in many ways similar to the modern Caspian biota, and in particular cases can be regarded as its precursor.

2009) Galeacysta etrusca complex: Dinoflagellate cyst marker of paratethyan influxes to the Mediterranean sea before and after the peak of the messinian salinity crisis, Palynology, 33:2, 105-134, AbstractMore than one thousand specimens of a morphological complex including Galeacysta etrusca Corradini & Biffi 1988 from 11 Upper Miocene and Lower Pliocene localities of the Paratethyan and Mediterranean realms have been studied using a biometric approach in part relating to the degree of separation between endocyst and ectocyst. Four stable biometric groups have been distinguished statistically, the occurrence or prevalence of which appears closely linked to environmental conditions irrespective of the realm. Group 'a' is related to brackish conditions, group 'b' to marine conditions, group 'c' to freshwater, and group 'd' to high nutrient levels. Based on an accurate chronology provided by calcareous nannoplankton bioevents and recognition of the Messinian Erosional Surface, this study reveals:Palynology, 33 (2) 2009:105-134 Downloaded by [Northeastern University] at 17:47 01 December 2014 106 PALYNOLOGY, VOLUME 33(2) -2009(1) the high sensitivity of the Galeacysta etrusca complex for reconstructing paleoenvironments and discriminating phases of connection and isolation of basins;(2) the detailed history of this species complex which originated in the Pannonian Basin at ca. 8 Ma before invading the Dacic Basin during the interval 6-5.60 Ma, then migrating into the Mediterranean during high sea-level connections (the 'Lago Mare' events just before and after the peak of the Messinian Salinity Crisis, i.e. at 5.60 Ma and during the interval ca. 5. respectively), and finally into the Black Sea at ca. 5.13 Ma;(3) an improved paleogeography for the Mediterranean and Paratethyan realms with focus on the location of corridors and the timing of when they were active.Based on field observations and dinoflagellate cyst data, we propose that the reflooding of the Mediterranean Basin by Atlantic waters occurred at ca. 5.46 Ma, about 130 kyr before the Zanclean GSSP (5.332 Ma).

AB STRA CT Middle and Late Miocene palynological biozonation of the southwestern parts of Central Paratethys (Croatia) is presented based on organic-walled phytoplankton. Nine characteristic palynozones of regional palynostratigraphic range are recognized, e.g. Early Badenian (Langhian) Cribroperidinium tenuitabulatum (Cte), Badenian (Late Langhian-Earliest Serravallian) Unipontidinium aquaeductum (Uaq), Late Badenian (Early Serravallian) Cleistosphaeridium placacanthum (Cpl), Sarmatian (Middle and Late Serravallian) Polysphaeridium zoharyi-Lingulodinium machaerophorum (Pzo-Lma), early Early Pannonian s.l. Mecsekia ultima-Spiniferites bentorii pannonicus (Mul-Spa), middle Early Pannonian s.l. Spiniferites bentorii oblongus (Sob), late Early Pannonian s.l. Pontiadinium pecsvaradensis (Ppe), early Late Pannonian s.l. Spiniferites validus (Sva), and late Late Pannonian s.l. Galeacysta etrusca (Get). As inferred from the regional palynostratigraphic correlation, the signals of two transgressions after the isolation of Paratethys during the Sarmatian are recognised: the fi rst one in the late Early Pannonian, when Mediterranean dinofl agellates migrated into the Pannonian Basin, and the second one in the Late Pannonian, when endemic Paratethyan taxa migrated into the Mediterranean.

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