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The early Miocene mollusc faunas from the Proto-Mediterranean Sea are still poorly-known. Herein, Aquitanian gastropod assemblages from the Felli section in NW Greece are described. Two assemblages were recovered, a low-diversity coastal mudflat assemblage dominated by Granulolabium plicatum (Bruguière, 1792) and Mesohalina margaritacea (Brocchi, 1814), and a high-diversity marine assemblage dominated by Bittium larrieyense (Vignal, 1911). The marine assemblage yielded 44 species, of which three species are described as new and 23 are left in open nomenclature. A new combination is proposed for Finella perpusilla (Grateloup, 1827). The family Pyramidellidae is exceptionally represented by 15 species. 17 new occurences are reported for the Proto-Mediterranean Sea. Alvania amphitrite n. sp., Homalopoma acaste n. sp. and Pyramistomia aliakmoni n. sp. are introduced as new species. © 2019, Museum National d'Histoire Naturelle. All rights reserved.

We present a taxonomic and palaeoecological analysis of a continental mollusc fauna from a mammoth-bearing succession near Bullendorf in Lower Austria. The taxonomic analysis comprises morphological descriptions and SEM documentation of 15 Pleistocene gastropod species. A Principal Component Analysis of the quantitative and qualitative composition of the investigated samples reveals a stratigraphic succession of four mollusc assemblages defined herein as Galba truncatula assemblage, Succinella oblonga assemblage, Pupilla muscorum/loessica and Pupilla alpicola/sterrii assemblages. The autecological requirements of the species of each assemblage allow a reconstruction of the palaeoenvironmental history of the section with alternating dry and humid conditions within a general cooling trend. Despite generally low mollusc density and species richness, the Bullendorf site allows important insight into latest Quaternary regional environmental conditions and climate. Based on the comparison with similar mollusc sites across Europe, a biostratigraphic correlation with the Late Pleistocene (~110–12 ka) is proposed., Rivista Italiana di Paleontologia e Stratigrafia (Research In Paleontology and Stratigraphy), V. 124, N. 3 (2018)

Accurate and precise dating of meteorite impacts is a prime intent of stratigraphic, paleoclimatic, and paleonto-logical research. Robust age estimates, however, exist only for 11 of 174 confirmed impacts structures (ref. 1) including the Ries crater in Germany, one of the best studied impact structures on Earth. This is probably also the impact site with the highest number of radiometric age determinations. So far, published ages are exclusively based on the analysis of impact-generated melts, i.e. suevite glass and/or moldavites (tektites) (e.g., ref. 2-7) and feldspar melt (ref. 8). However, despite more than 60 individual isotopic age data obtained during 50 years of research there is no consensus as to the accurate age of the impact. For example, 40Ar-39Ar ages range from 15.2 Ma (ref. 2) to 14.3 Ma (ref. 6,7), with the young ages representing most of the recent age determinations. Accordingly, the long-standing estimate of about 15 +- 0.2 Ma (ref. 2,3) has been criticized recently as being too old by more than 0.5 Ma (e.g., ref. 1, 5-8) and only confirmed once (ref. 9). Ages < 14.6 Ma, however, pose severe problems on geophysical and biostratigraphic interpretations. Most significantly and central to the discussion, they are in conflict with a reversed magnetic field during impact (ref. 10,11), because a normal magnetic field persisted from about 14.6 to 14.15 Ma (ref. 12), i.e. impact ages < 14.6 Ma are impossible from a paleomagnetic point of view.

Lake Sinj formed in a 342 km2 large, rhomboidal, NW-SE elongated pull-apart basin. The basin was initiated in the Early Miocene, following the traspressional wrenching of the External Dinarides due to northward oblique-slip motions of the under-thrusting Adriatic block. Its sedimentary infill comprises exclusively lacustrine deposits and attains an average thickness of about 370 m. The basin formed in a karst environment. Whereas the pre-Neogene basement is dominated by Mesozoic platform carbonates along the basin margins, extensive Permian evaporite deposits with a direct sedimentary contact with the basal lake sediments occur beneath the basin. Doming of those evaporites decreased subsidence rates within the basin. The presence of steep hinterland topography is pinpointed by massive breccia intercalations into marginal lake deposits. The lake sedimentation is dominated by authigenic carbonates ; the siliciclastic input is minor to absent. The basal and the uppermost beds include coal seam intercalations, whereas the middle part of the infill shows exclusively carbonate rocks intercalated occasionally by volcanic ash layers. The section investigated in detail is about 140 m thick and provides insight into the upper coal bearing part of the infill and its transition into the central part. The paleoenvironmental analysis combining sedimentology, microfacies analysis, coal petrology and paleoecology of molluscs and plant remains, inferred a variety of environments including (1) littoral below the fair weather wave base, (2) littoral above the fair weather wave base, (3) infralittoral with vegetated areas dominated by aquatic, perennial plants, (4) low supralittoral to upper infralittoral with starfruit meadows, (5) areas covered by cyanobacterial mats, (6) carbonate marshes, (7) peripheral swamps, (8) stream catchments areas and low-lying mires, which were (9) more or (10) less frequently flooded. The latter environment was inhabited by large land mammals related to elephants and rhinoceroses. Two depositional systems with several cyclic changes were traced, both of them related to a shallow water marginal environment. The first one resulted from deposition within rather stable littoral conditions. It was characterized by relatively uniform sedimentation of bedded limestones. That depositional phase was accompanied by conspicuous accumulations of starfruits (Damasonium), but otherwise a remarkable low biotic diversity. The fossil-poor intervals were interpreted as phases of repetitive lake acidification due to periodical flooding of marginally established starfruit meadows during the lake high stands. That induced the input of H+ ions from aerated limy mud into the water column of the lake. The catastrophic influence of repetitive chemical disturbance hindered the evolutionary progress of the ecosystem. The second depositional system type differs from the previous one by a slight decrease in lake level. Consequently, the shallower environment was more prone to lake level fluctuations. The changing conditions resulted in alternating limestones and coal seams. That alternation was triggered by a short-term, orbitally forced cyclic fluctuation of humid and dry periods. That phase, characterized by stable hard-water lake conditions, witnessed a spectacular diversification of the ecosystem followed by a significant morphospace increase in melanopsid and hydrobiid snails. The study was funded by the Austrian FWF Project P18519-B17: "Mollusk Evolution of the Neogene Dinaride Lake System" and by the Republic of Croatia, Ministry of Science, Education and Sports Projects: "Neogene terrestrial environments of the Pannonian Basin and karst region" no. 195-1951293-2703, and "Evolutionary changes of the Dinarides from subduction to modern Adriatic beaches" no. 119-1191155-1159.

The Karpatian and Badenian paleogeography is descibed.