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The morphology of fossil remains of Vestalenula (Darwinuloidea, Ostracoda) from Crete (Greece), Serbia and Italy were analysed using morphometric valve variability analysis. Three new species were distinguished and described, Vestalenula angulata n. sp., Vestalenula longissima n. sp. and Vestalenula pliocenica n. sp., and represent the first record of this genus in the Neogene of Italy and Serbia. Vestalenula angulata n. sp. was recorded from the early Messinian of Tuscany, Italy (Baccinello and Velona Basins), Vestalenula longissima n. sp. was collected in the Upper Pliocene (Gelasian) sediment core drilled in the Sabina area (Latium, Italy), and Vestalenula pliocenica n. sp. was collected from the Early Tortonian of Vrysses (Rethymnon Basin, Crete), from the lower Messinian deposits of the Velona Basin (Tuscany, Italy), in the Late Pliocene of the Paludinian Beds (Middle Danube Plain) and Mazgoš deposits (Serbia), and in the Upper Pliocene deposits of the Sabina area (Latium, Italy). Despite the freshwater character of most living species of Vestalenula, the fossil species here analysed were found associated with halotolerant forms, showing they could also withstand oligohaline conditions.

A gigantic cascade of Atlantic waters, filling the deep desiccated Mediterranean basin at the beginning of the Pliocene, has commonly been envisaged to end the Messinian Salinity Crisis (MSC). The Mediterranean lowstand during its final “Lago-Mare” phase, however, has long been subject to major controversy and has recently been seriously questioned again. Here, we present high-resolution ostracod distribution patterns of the MSC successions in the Black Sea basin (Zheleznyi Rog section; Russia) and the Mediterranean (Cuevas del Almanzora section; Spain) to study the origin and migration history of the Lago-Mare ostracods. We conclude that two major phases of faunal migration have taken place in the Messinian. The first phase corresponds to the Maeotian–Pontian boundary interval (~ 6.1–6.0 Ma) of the Paratethys, where mainly Pannonian species suddenly invaded the Black Sea region. The second migration event corresponds to the Lago-Mare phase of the Mediterranean when first (5.55–5.47 Ma) some opportunistic taxa (species of Cyprideis and Loxoconcha genera) and then (5.40–5.33 Ma) a more diverse assemblage of Paratethyan species occupied the entire Mediterranean region. The Spanish ostracod assemblages show a high percentage of Paratethyan (Pontian) ostracods, in agreement with previously studied Italian Lago-Mare sections. The similar palaeoenvironmental changes that developed roughly synchronously in the western and central Mediterranean marginal basins provide more evidence for intrabasinal exchange at high water level during the final stage of the Lago-Mare phase. This indicates that the Mediterranean in the latest Messinian was full of water (comparable to the present Caspian Sea) and that the Zanclean deluge, if happened, only surged some tens, up to few hundred metres, into the Mediterranean.

The nine papers collected in this special issue of Micropaleontology are a selection of contributions on presented at the 17th International Symposium on Ostracoda (ISO), which was held in Rome, Italy, on 23rd-26th July 2013, and attended by 141 scientists from 29 countries (see text-figure 1).

Ostracoda are microcrustaceans whose soft parts are enclosed in a bivalve carapace composed of low-Mg calcite. Their small dimensions (0.4 to 2.0 mm on average) and hard parts coupled with a long evolutionary history (from Ordovician to Present) and adaptation to all kinds of aquatic habitat make them a successful taxonomic group for paleontological analyses (Rodriguez-Lazaro and Ruiz-Muñoz, 2012). Ostracoda are mainly benthonic and are very strictly linked to their environment. They are particularly sensitive to salinity, depth, temperature, and bottom substrate, as well as hydrochemistry, nutrient content, and pollution. In addition, their carapace is a source of biogenic carbonate, suitable for geochemical studies (Ito et al., 2003). For all these reasons, Ostracoda represent an excellent proxy for the studies of paleoenvironmental changes during the Phanerozoic (Boomer et al., 2003) aswell as for climate reconstructions during Quaternary as widely demonstrated by the recent volume edited by Horne et al. (2012). The present volume, “Ostracoda as proxies for palaeoenvironmental changes — Selected papers from 17th ISO” assembles selected research on paleoenvironments based on Ostracoda that was presented at the 17th International Symposium on Ostracoda, held in Rome (Italy) from the 22nd to the 26th of July, 2013. Prior to this volume, three special issues of Palaeogeography, Palaeoclimatology, Palaeoecology (Holmes and Horne, 1999; Ikeya et al., 2005; Mischke and Holmes, 2008) have stemmed from the International Symposium on Ostracoda (ISO), one of the largest international micropaleontological conferences with a focus on a single microfossil group. The ISO meetings bring together ostracod researchers from all around the world every 4 years to discuss and exchange classic and novelmethods and applications in the study of Ostracoda in a professional but collegial atmosphere. Presentations at these symposia have often been the prelude to notable and significant publications that have advanced our knowledge on the biology, taxonomy, evolution, and ecology of this group of micro-crustaceans and enhanced their application to the earth sciences. The principle of publishing these works in a special issue of a prestigious international journal such as Palaeogeography, Palaeoclimatology, Palaeoecology is intended to bring the latest developments in ostracod research not just to ostracodologists, but also to the wider earth science scientific community.

The living euryhaline species Cyprideis torosa (Jones) undergoes morphometric variations in size, noding and sieve-pore shape linked to the environmental salinity. In particular it is known that salinity values around 8-9 psu represent the osmoregulation threshold and also the turning point between smaller and greater valve dimensions and prevailingly noded against un-noded valves. The variation of the percentage of round-, elongate- and irregular-shaped sieve-pores on the valves has shown an empiric logarithmic correlation with the water salinity from 0 to 100 psu. Due to this ecologically cued polymorphism, C. torosa represents 28 an invaluable palaeosalinometer for the Quaternary brackish basins. In this paper we attempt to verify whether the ecophenotypical behaviour of the post-evaporitic Messinian species Cyprideis agrigentina Decima was comparable with that of C. torosa. To reach this goal, three morphometric characters have been analysed: 1) size variability; 2) noding and ornamentation; 3) variability of the percentage of the sieve-pore shapes. The palaeoenvironmental interpretation was made using synecological and geochemical approaches [stable isotopes, trace elements, Sr-isotopes and natural radioactivity (NRD)]. For this study, the 250 m-thick Messinian Lago-Mare succession of Eraclea Minoa (Agrigento, Sicily) was chosen for the presence of monotypic assemblages made only by C. agrigentina for around 70 m of thickness. The results of the morphometric analyses showed that: 1) size variations are not related to the salinity changes recognized both from synecological and geochemical analyses; 2) no noded specimens have been recovered along the section; 3) the salinities calculated on the basis of the percentage of the sieve-pore shape are not correlated with the salinities inferred from the synecological and geochemical analyses. Thus in this paper we conclude that C. agrigentina cannot be considered a palaeosalinometer for the Messinian Salinity Crisis. There is a correlation of the 13 C and NRD data with the percentages of sieve-pore shapes, linking them to the oxygen availability at the bottom of the basin.

The 7.5 m long SK13 sediment core, drilled at Lake Shkodra (Albania) bottom depth of 7 m in the central southern part of the lake, was selected for multidisciplinary analysis. Ostracods, Characeae, pollens, and stable isotopes were studied with the aim to reconstruct the past biodiversity and the palaeoenvironmental and palaeoclimatic changes occurred during the Middle-Late Holocene. The chronological framework of SK13 was already known and well constrained through radiometric datings. The sediment core age spans from 4560 cal year BP to present. Thirteen ostracod and five charophyte species were identified. Among them, the ostracods Candona montenigrina and Limnocythere scutariense are endemic of the lake; Candona meridionalis and Paralimnocythere georgevitschi have been collected for the first time in the Lake Shkodra while formerly were considered endemic respectively of Lake Dojran and Lake Prespa; Metacypris cordata, ?Carpathocandona sp., and Cyclocypris sp. were never recorded in the lake and were found only in the lower portion of the sediment core. Among the charopytes, Lychnothamnus barbatus and N. hyalina are recorded for the first time in the lake and occurs with high frequency throughout interval A of core. The faunal composition is quite homogeneous, with the percentages of the different species varying along the sediment core. The main change occurs between 1274 and 1197 cal yr BP, where charophytes disappear abruptly as well as 8 ostracod species out of 13, and the frequency of the remaining 5 species dramatically increases. Moreover at that moment, it occurs also the appearance of a peculiar not-tuberculate morphotypes of Ilyocypris monstrifica. The micropaleontological data suggest a decrease of the lake biodiversity since around 1200 cal years BP linked to the transition between an ancient marshland to a lacustrine environment. This drastic change seems to be independent from any global or local climate changes and could be related to the co-occurrence of two phenomena: 1) the Adriatic sea level rise during the Middle and Late Holocene, that that would have uplifted the base level of the River Bojana causing a decrease of its discharge and, consequently, reducing the drainage of the water from the Shkodra swamp; 2) the periodical change of the River Drin course over the last five centuries, which, when deviated into the Bojana river, blocked the River Bojana outflow.

Ilyocypris Brady & Norman, 1889 is a widespread freshwater ostracod genus including about 30 living and 190 fossil species. The specific identification of the living Ilyocypris relies mainly on the appendages, being an identification exclusively based on valves rather complicated because of the high intraspecific variability of their characters in several species. This study aims to test the taxonomic significance of the carapace characteristics through the examination of specimens unambiguously identified on the basis of their soft part morphology, in order to provide useful taxonomic criteria for the identification of Ilyocypris shells in fossil assemblages. Sixty-five ilyocypridid specimens collected in mainland Italy and surrounding islands were analysed. All specimens were dissected and soft parts checked in light microscopy. The patterns of valve surface ornamentation and of marginal ripplets were examined by electron microscopy. Moreover, the geometric morphometric analysis of the valve outlines was performed. Sixty-two specimens could be easily accommodated in eight Ilyocypris species (I. bradyi, I. decipiens, I. getica, I. gibba, I. hartmanni, I. inermis, I. monstrifica, and I. salebrosa) according to the morphology of their appendages. Three additional specimens, with soft parts typical of Ilyocypris but clearly distinct valve morphology, were left in open nomenclature. Our results show that the outline analysis is often a valid tool to discriminate between different species. Conversely, valve ornamentation displays different degrees of intraspecific variability in some Ilyocypris species. The marginal ripplets are constant within each species, but they do not always mirror the patterns reported by other authors; therefore, we do not consider them as reliable diagnostic character for specific determination. This study confirms that the identification of Ilyocypris species requires accurate description of appendages as well as external and internal carapace characteristics, and stresses the advantage of a combined neontological and paleontological investigation in solving taxonomic problems related to non-marine ostracods.

The aim of this paper is to re-describe LIVENTAL’s (1929) species through the SEM pictures of the specimens included in various historical collections deposited at the Micropaleontological Laboratory of the VNIGRI, St. Petersburg, Russia, since the original Livental’s collection seems to be lost as well as the Azerbaijan collections by Agalarova (AGALAROVA, 1956, 1967; AGALAROVA et al., 1940, 1961). In particular, the revision is based on the VNIGRI collection AZNII27 of L.N. Klein who studied the ostracods of the Azerbaijan area of Babazanan (KLEIN, 1960, the same area studied by LIVENTAL, 1929) and on several other collections from Turkmenistan, the Caucasus and Euxinic/Black Sea? Basin included both in historical collections (Mandelstam, Luebimova, Rozjeva, Stepanaitys) as well as on new findings from the Euxinic Basin. The discussion on each species is accompanied by its synonymy, and an updated geographical and stratigraphical distribution based on the new chronostratigraphical data of KRIJGSMAN et al. (2010) and VAN BAAK et al. (2013). In those few cases where the Livental’s species are still living in the Caspian or Black Sea, the soft parts are described and the ecological parameters given.

During September 2003 several cores were drilled from the Albanian side of Lake Shkodra. Among them, a 7,8 m long composite core (SK13), drilled at a lake bottom depth of 7 m in the central southern part of the lake (42°6’11.65”N, 19°25’18.96”E) has been selected for multidisciplinary analysis. Ostracods, characeae, pollen, CaCO3 content and stable isotopes were studied with the aim to reconstruct the palaeoenvironmental and palaeoclimatic changes occurred during the Late Holocene. The chronological framework of SK13 was established through the recognition of four well-dated tephra layers and four 14C accelerator mass spectrometry measurements; the sedimentation rate has been calculated as spanning between 1.1 and 3.0 mm/yr in the different portions of the composite sediment core (SULPIZIO et al., 2010, VAN WELDEN et al., 2008).

The Legnagnone section (North-eastern Apennines) represents one of the few shallow water records of the onset of the Messinian salinity crisis. Here we present a detailed description of a ~200 kyr time interval encompassing the pre-/syn-evaporitic transition based on a multidisciplinary approach, integrating sedimentological, bio-magnetostratigraphical, palaeontological and stable isotope data. Such a shallow water setting is potentially more sensitive to the palaeoenvironmental change leading to the MSC than the more often studied deeper Mediterranean basin. The aquatic palaeoenvironmental reconstruction proposed here is based on the study of foraminifer, ostracod and mollusc assemblages. It depicts a change from infralittoral (20–50 m) to inner circalittoral environment (60–100 m) that, since 6.12 Ma, was progressively affected by a reduction of oxygen at the sea floor punctuated by short-lived anoxic events. At least three cooling events have been recognized on the basis of relative abundance data in mid to high altitude pollen, which, before 6.03 Ma, are in phase with abundance peaks of Turborotalia spp., a taxon indicating eutrophic and cool surface waters. The absence of stress-tolerant benthic foraminifers during these peaks points to strong ventilation episodes triggered by a generally cooler climate. The proximity of a deltaic system and the consequent riverine input probably caused a salinity decrease of the surface waters, hindering the proliferation of planktonic foraminifers in the water column, which prevalently occur in short influxes and disappear at ca. 6 Ma. Our results suggest that the onset of the crisis occurred during a phase of relative sea level high stand, whereas no evidences of sea level drop can be envisaged. The palaeoclimatic reconstruction based on palynological data indicates the dominance of a “subtropical humid forest” vegetation type, where fresh water swamps are well represented. From 6.03 Ma onward, the transition to the salinity crisis is marked by more pronounced cyclical expansions of the temperate broad-leaved deciduous forest, along with herbaceous taxa. The establishment of the strongly evaporative condition at the crisis onset is not associated with major vegetational changes towards drier conditions, but linked to a sudden increase of δ18O and the disappearance of benthic foraminifers just prior to the deposition of the 1st laminated carbonate, which represents the base of the Primary Lower Gypsum unit.

The relationship between ostracod and macrophyte communities has been seldom studied, especially in urban parks. The main purpose of this research is to explore such a relationship in the area of Rome, and in particular in the Appia Antica Regional Park (Rome, Italy), to provide information about the environmental characteristics influencing both the assemblages and to document for the first time the distribution of freshwater ostracods in an area inside the city of Rome. The survey has considered different water bodies: springs, channels, ditches and a pond. Chemical and physical parameters were measured during the ostracod sampling in 13 sites during the 4 different seasons. The ostracod assemblage includes 11 species whereas the macrophyte community is formed by 17 species. Their link with the measured abiotic parameters has been studied through several statistical analyses: cluster analysis, non-metric multidimensional scaling and canonical correspondence analysis. The results clearly separate the investigated area in one sector where COD and phosphates are the driving factors and another sector where inorganic nitron ions, pH and conductivity are the main influencing factors. To better understand the ostracod-macrophyte interaction, Spearman rank-order correlation analysis was performed, confirming such a link. Although the macrophyte community is clearly affected by human pressure, the relationship with the ostracod assemblages seems well established and identified by exclusive pairs or groups of species. Among them, the Cypria lacustris-Lemna minuta duo is of considerable importance, being L. minuta an exotic species, known as an invasive weed in some areas of Europe and spread in Italy only recently. The fact that the 13 sites were characterized by different public access regulation has been partially mirrored by both ostracod and macrophyte distribution since the majority of the sites characterised by the highest diversity are those with restricted access. In general, notwithstanding the anthropic pressure, the occurrence of different kinds of water bodies has allowed the development of ostracod and macrophyte associations, which are rarely represented in an urban park.

The historical site of the Monte Mario lower Pleistocene succession (Rome, Italy) is an important marker of the Pliocene/Pleistocene boundary. Recently, the Monte Mario site was excavated and restudied. A spectacular angular unconformity characterizes the contact between the Monte Vaticano and the Monte Mario formations, which marks the Pliocene/Pleistocene boundary. Biostratigraphical analyses carried out on ostracod, foraminifer, and calcareous nannofossil assemblages indicate an Early Pliocene age (topmost Zanclean, 3.81–3.70 Ma) for the underlying Monte Vaticano Formation, whereas the Monte Mario Formation has been dated as early Pleistocene (Santernian, 1.66–1.59 Ma). Palaeomagnetic analyses point to C2Ar and C1r2r polarity chrons for the Monte Vaticano and the Monte Mario formations, respectively. The Monte Mario Formation consists of two obliquity-forced depositional sequences (MM1 and MM2) characterized by transgressive systems tracts of littoral marine environments at depths, respectively, of 40–80 m and 15–20 m. The data obtained from foraminifer and ostracod assemblages allow us to reconstruct early Pleistocene relative sea-level changes near Rome. At the Plio/Pleistocene transition, a relative sea-level drop of at least 260 m occurred, as a result of both tectonic uplift of the central Tyrrhenian margin and glacio-eustatic changes linked to early Pleistocene glaciation (Marine Isotope Stage 58).

Dans ce travail, les ostracodes trouv´es dans dix complexes coralliens du Mioc`ene sup´erieur construits par Siderastrea, Tarbellastrea et Porites, localis´es dans la plaine de Messara (zone m´eridionale du bassin de l’Iraklion, Cr`ete centrale) sont ´etudi´es et illustr´es. Cinq diff´erentes associations caract´eristiques des divers environnements marins ont ´et´e reconnues par : (1) association des couches silteuses basales, caract´eris´ee par des esp`eces typiques des eaux marines du domaine infralittoral sup´erieur, parmi lesquelles Cyamocytheridea meniscus, Cyamocytheridea obstipa, Cyamocytheridea dertonensis, Cytheretta semiornata et Nonurocythereis seminulum sont tr`es repr´esent´ees ; (2) association des couches r´ecifales avec Grinioneis haidingeri, Aurila cicatricosa, Cimbaurila diecii, Tenedocythere cruciata, Pokornyella italica et Callistocythere quadrangula dominants qui indiquent un environnement marin infralittoral sup´erieur stable, caract´eris´e par des eaux chaudes et bien oxyg´en´ees ; (3) association des couches silteuses interpos´ees entre les complexes coralliens, parmi lesquelles Neomonoceratina laskarevi, Cytheridea acuminata, Phlyctenophora farkasi, Aurila albicans Callistocythere spp., Xestoleberis communis et X. dispar sont dominants. Ces esp`eces indiquent des eaux peu profondes avec v´eg´etation aquatique ; (4) association des couches silteuses sup´erieures, domin´ee par la pr´esence du genre Xestoleberis, caract´eristique des environnements marins moins profonds et tr`es riches en flore aquatique et (5) association des couches argilosilteuses terminales, domin´ee par Hemicytherura defiorei, Ostracods from ten Late Miocene coral reef complexes built by Siderastrea, Tarbellastrea and Porites, cropping out in the Messara Plain (southern Iraklion basin, central Crete), have been investigated and five assemblages have been recognised, which point to different marine environments: (1) assemblage from the basal sandy silts, dominated by very shallow inner-infralittoral species, such as Cyamocytheridea meniscus, Cyamocytheridea obstipa, Cyamocytheridea dertonensis, Cytheretta semiornata and Nonurocythereis seminulum; (2) assemblage from the coral reef complexes within which Grinioneis haidingeri, Aurila cicatricosa, Cimbaurila diecii, Tenedocythere cruciata, Pokornyella italica and Callistocythere quadrangula are dominant and point to a stable inner-infralittoral environment characterised by warm, quiet and well-oxygenated waters; (3) assemblage from the silts intercalated among the coral reef complexes, mainly characterised by Neomonoceratina laskarevi, Cytheridea acuminata, Phlyctenophora farkasi and Aurila albicans together with Callistocythere spp., Xestoleberis communis and Xestoleberis dispar, which points to a very shallow marine environment rich in aquatic vegetation; (4) assemblage from the upper silts, which records the absolute dominance of Xestoleberis species, reflecting a very shallow and highly-vegetated environment and (5) assemblage from the uppermost silty clays, dominated by Hemicytherura defiorei, Xestoleberis spp. and Palmoconcha dertobrevis, accompanied by Acanthocythereis hystrix, Cytherella scutulum, Bairdoppilata conformis, Semicytherura spp., Krithe sp., Cytheropteron alatum, Bythocypris sp. and Pseudocythere caudata, which suggest deeper marine environments probably located in the outer infralittoral/inner-circalittoral zones. The studied section has been dated by means of calcareous nannoplankton to be not younger than Zone MNN9 (Early Tortonian), which is the biostratigraphical datum recorded in the fine-grained deposits that overlie the coral reef complexes. An age not older than Tortonian can be inferred by the stratigraphical distribution of the recognized ostracods. Thus, the coral reef complexes have been tentatively referred to the Early Tortonian.

In this paper the preliminary results of the analyses on the ostracod assemblages coming from the Middle– Late Pliocene Tiberino Lake (Umbria, central Italy) are discussed. Three sections have been investigated, Cava Toppetti and Fosso Bianco, whose sediments record a deep lacustrine facies, and Dunarobba, which represents the littoral facies of the lake. Cava Toppetti and Fosso Bianco ostracod assemblages are very similar, made exclusively by Candonidae (six genera and eleven species, nine of which are new) and Limnocytherinae (one genus including one new species), while at Dunarobba the assemblages are more diversified, including Candonidae (four genera and five species), Limnocytherinae (one genus including one new species), Ilyocyprididae (one genus and three species), Cytherideinae (one genus and two species) and Cyprididae (two genera and two species, one of which is new). On the whole, the Tiberino Lake ostracod assemblages seems to be characterised by a high degree of endemism, particularly in the deep lacustrine facies (up to 83%) and, among the Candoninae, intralacustrine speciation is recognizable for genera Candona (Neglecandona), Sirmiella and “Caspiocypris”. This latter gives rise to a “species flock”. The characteristics of the collected ostracod fauna, coupled with the long duration of the lacustrine sedimentation (1.8 Ma) concur to suggest that the Middle–Late Pliocene Tiberino Lake was a “palaeo–ancient lake”.

Recenti lavori per la costruzione, nella città di Roma, del Passante a Nord-Ovest (Galleria Giovanni XXIII) hanno permesso di raccogliere nuovi dati circa la stratigrafia e l’assetto tettonico del settore dei Monti della Farnesina, in riva destra del F. Tevere. Le gallerie naturali del Passante a Nord-Ovest hanno attraversato la successione plio-pleistocenica di Monte Mario, che è stata suddivisa in due formazioni: la formazione di Monte Vaticano e la formazione di Monte Mario. Quest’ultima, poggiante in discordanza stratigrafica al disopra della formazione di Monte Vaticano (Marne Vaticane Auct.), è stata distinta in cinque membri: 1) Limi di Farneto; 2) Sabbie grigie ad Arctica islandica; 3) Sabbie gialle con panchina; 4) Sabbie gialle con intercalazioni limose; 5) Argille, sabbie e limi con Cerastoderma. La forte troncatura erosiva osservata al top della formazione di Monte Vaticano suggerisce la presenza di un’ampia lacuna stratigrafica erosivo-deposizionale, tra questa e i soprastanti depositi della formazione di Monte Mario. Le analisi biostratigrafiche e paleoecologiche condotte in questo studio hanno messo in evidenza differenze sostanziali tra la formazione di Monte Vaticano (Marne Vaticane Auct.) e i soprastanti Limi di Farneto. Le Marne Vaticane Auct. campionate lungo il Passante a Nord-Ovest hanno fornito associazioni di plancton calcareo riferibili allo Zancleano inferiore (3.85-3.58 Ma). L’analisi paleoecologica condotta sulle ostracofaune indica, per le Marne Vaticane Auct., un ambiente batiale superiore, con paleoprofondità comprese tra –200 e –350 m. Per quanto emerso dall’analisi dei nannofossili calcarei, i Limi di Farneto sono collocabili al disopra della FO di medium Gephyrocapsa (Santerniano inferiore). Inoltre, per la sostanziale assenza di C. macintyrei e per la presenza di B. etnea, è possibile limitare l’età dei Limi di Farneto all’interno dell’intervallo 1,60-1,49 Ma (Santerniano superiore). L’analisi paleoecologica dell’orizzonte basale dei Limi di Farneto ha fornito indicazioni di un ambiente infralitorale esterno, con paleoprofondità di circa –40 m e un abbassamento relativo del livello del mare di almeno 160 m. Tale abbassamento relativo ha un’origine prevalentemente tettonica, dal momento che le Marne Vaticane Auct. risultano interessate da sistemi di faglie estensionali suturate dalla soprastante formazione di Monte Mario. All’interno della formazione di Monte Mario, l’analisi paleoecologica condotta sulle ostracofaune ha consentito di riconoscere due diverse sequenze deposizionali, separate da una superficie di discontinuità, legata ad un momento di abbassamento relativo del livello del mare, che definisce il limite Sabbie gialle con panchina\Sabbie gialle con intercalazioni limose. La base delle Argille, sabbie e limi con Cerastoderma corrisponde ad un secondo evento trasgressivo, riconosciuto all’interno della formazione di Monte Mario, che ha portato alla deposizione di argille marine di ambiente infralitorale, come la base dei Limi di Farneto, caratterizzate, ancora, dalla presenza di medium Gephyrocapsa. L’analisi strutturale e le indicazioni del fabric magnetico, indicano che l’alto di Monte Mario si è strutturato in due fasi tettoniche estensionali distinte: 1) una prima fase, sviluppata su piani NE-SW, collocabile prima della deposizione della formazione di Monte Mario (pre Santerniano superiore); 2) una seconda fase sviluppata su piani NW-SE, in un intervallo temporale compreso tra 750-600 ka. Infine, i caratteri paleomagnetici delle formazioni di Monte Mario e di Monte Vaticano mostrano componenti di polarità inversa ben definite, attribuite sulla base dei dati biostratigrafici, rispettivamente, all’epoca MATUYAMA ed alla parte superiore dell’epoca GILBERT.

La successione tardo messiniana di Fonte dei Pulcini (FPA) (Maiella sud-orientale), deposta in un bacino di avampaese, ha registrato numerose variazioni paleoambientali in termini di paleoprofondità, paleosalinità, apporto detritico, evaporazione/precipitazione e aridità/umidità. Queste variazioni paleoambientali sono state messe in evidenza attraverso l’analisi integrata di dati paleontologici, geochimici e mineralogici. L’analisi della suscettività magnetica nella successione di FPA ha permesso di effettuare una calibrazione astrocronologica delle variazioni paleoambientali e paleoclimatiche, vincolando la sezione tra 5,394 e 5,335 Ma. Confrontando la curva dell’insolazione con le variazioni paleoambientali registrate dalla sezione FPA è stato messo in evidenza un ritardo di 5-8 ka tra la causa astronomica della variazione climatica e la risposta del bacino sedimentario.

A high-resolution stratigraphic model for the uppermost Messinian deposits of the Mediterranean basin is here proposed. The model provides new constraints for calibrating the time and space distribution of palaeoenvironmental proxies of the final phase of the Messinian salinity crisis (MSC), characterized, after the main phase of massive evaporite precipitation, by the progressive and generalized establishment of brackish to freshwater aquatic environments throughout the Mediterranean basin (‘Lago Mare event’). The corresponding stratigraphic unit, bounded by the intra-Messinian unconformity (MES) at the base (~5.6 Ma) and the M/P boundary at top (5.33 Ma) is split into two sub-units by a minor unconformity marking a sharp facies change. The lower sub-unit (p-ev1) is localized in deepest and/or strongly subsiding basins and is commonly characterized by ‘regressive’ depositional trends. It records the transition from hyper- to hypohaline conditions over a short time span characterized by an acceleration of tectonic processes in many Mediterranean geodynamic contexts. The upper sub-unit (p-ev2) is more basin-wide distributed and records the generalized periodic activation of catastrophic flood-dominated fluvio-deltaic depositional systems, indicating important modifications in the drainage areas and/or in fluvial runoff. In this sub-unit four to five precessional cycles are usually recognized below the Miocene/Pliocene boundary, allowing basin-wide correlations and suggesting to place its basal age at around 5.42 Ma. While p-ev1 records the local and ephemeral development of Lago Mare environments with low-diverse, pioneer taxa, p-ev2 is marked by the diffusion of conspicuous brackish to freshwater fossil assemblages of increasing diversity and complexity upwards. The change is best approximated by the boundary between the two sub-units. No clear evidence of normal marine conditions established before the Zanclean flooding have been recognized. Converging sedimentary evolution and paleontologic record suggest that the last MSC phase was characterized by a dilution of the surface waters of a large, residual Mediterranean water body with strongly reduced ocean connections. These conditions likely resulted from a positive feedback loop between processes (increase of fluvial runoff, generalized subsidence, base-level rise, enlargement of shelf areas) promoting the establishment of progressively larger, more stable intra-basinal connections and water exchanges with the Paratethyan basins, up to the final full reopening of the Atlantic gateways.

Two possible alternative interpretations of the claimed Zanclean age (Popescu et al., 2007) of two historical lithostratigraphic units of the Northern Apennines, usually referred to as Late Messinian in age and recording the so called Lagomare final event of the Messinian salinity crisis (MSC), are here discussed. The wrong age attribution of the Colombacci and ‘‘tetto’’ Fms. is ruled out based on data from the Maccarone and other sections showing that the Colombacci-Argille Azzurre Fm. boundary is basin wide synchronous and coincident with the Miocene-Pliocene boundary as far as it has been formally defined in the Eraclea Minoa GSSP. Alternatively, the opportunity of emending the Zanclean GSSP to a stratigraphically lower horizon recording the first evidence of marine influences in the Mediterranean following the MSC peak, seems not suitable, as (1) the marine signature of uppermost Messinian deposits is weak and still controversial and (2) no significant bio- and magnetostratigraphic events, well chronologically defined and recognizable at a global scale appear to be available to such a purpose.

In this paper two different Italian late Messinian lago-mare ostracod assemblages, dominated mainly by extinct Paratethyan species, have been analysed by means of Detrended Correspondence Analysis (DCA). The obtained plots have been compared and, with the help of the limited autoecological data on similar living species and geochemical data on the sediments in which they were included, the autoecology and synecology of the lago-mare assemblages have been inferred. In particular, it seems reasonable to suppose that: 1) assemblages made only by pointed candonids are typical of rather deep (possibly less than one hundred meters of depth) and freshwater/oligohaline environments; 2) assemblages mainly composed of Leptocytheridae point to shallow (probably few tens of meters of depth) and mesohaline waters; 3) diversified and even assemblages made both by pointed candonids and Leptocytheridae are common in rather deep (less than one hundred meters of depth) but oligo/low mesohaline environments; 4) Caspiocypris seems rather tolerant of brackish salinities, but prefers shallow environments; 5) Tyrrhenocythere could be an indicator of shallow and fresh/oligohaline waters. 6) Cyprideis is an indicator of shallow waters but can withstand a very wide salinity range.

Two possible alternative interpretations of the claimed Zanclean age (Popescu et al., 2007) of two historical lithostratigraphic units of the Northern Apennines, usually referred to as Late Messinian in age and recording the so called Lagomare final event of the Messinian salinity crisis (MSC), are here discussed. The wrong age attribution of the Colombacci and ‘‘tetto’’ Fms. is ruled out based on data from the Maccarone and other sections showing that the Colombacci-Argille Azzurre Fm. boundary is basin wide synchronous and coincident with the Miocene-Pliocene boundary as far as it has been formally defined in the Eraclea Minoa GSSP. Alternatively, the opportunity of emending the Zanclean GSSP to a stratigraphically lower horizon recording the first evidence of marine influences in the Mediterranean following the MSC peak, seems not suitable, as (1) the marine signature of uppermost Messinian deposits is weak and still controversial and (2) no significant bio- and magnetostratigraphic events, well chronologically defined and recognizable at a global scale appear to be available to such a purpose.

Nel presente lavoro sono state analizzate le ostracofaune ad affinità paratetisiana provenienti da diverse successioni di Lago-Mare tardomessiniane in Italia (successioni di wedge-top sul versante adriatico dell’Appennino settentrionale come Buttafuoco, Ca’ Blindana, Montepetra, Perticara e Maccarone, successioni di avampaese sul versante Adriatico dell’Appennino settentrionale e centrale, come Trave e Maccarone) e a Creta (Grecia) (successioni di Ano Akria e Faneromeni nel Bacino di Iraklion) e su di esse sono state effettuate analisi di comunità (numero di specie, indici di Margalef e Shannon-Wiener) ed analisi auto/sinecologiche. I risultati mostrano come, in generale, la porzione inferiore dei depositi post-evaporitici fosse caratterizzata da ambienti instabili che ospitavano comunità di ostracodi discontinue e caratterizzate da bassa biodiversità, mentre nella porzione superiore le condizioni paleoambientali erano maggiormente stabili, permettendo la suddivisione dell’iperspazio ambientale in diverse nicchie ecologiche e supportando così associazioni ad alta biodiversità. Tuttavia, la correlazione del limite tra associazioni a bassa ed alta biodiversità nelle successioni analizzate ha mostrato come quest’ultimo sia eterocrono, probabilmente a causa di fattori locali. Una ricostruzione paleoambientale dettagliata, effettuata comparando il susseguirsi di diverse associazioni di ostracodi lungo le diverse successioni, ha mostrato che, mentre nelle porzioni inferiori il paleoambiente era piuttosto disomogeneo, nelle porzioni superiori, in prossimità del limite Messiniano-Zancleano, si nota un trend generalizzato verso l’approfondimento e l’addolcimento, seguito da un nuovo incremento della salinità e da condizioni di acque più basse. L’analisi della curva dell’insolazione Laskar 2004 per l’intervallo di tempo in esame ha evidenziato una minore ampiezza dei picchi di massimo e minimo nella porzione inferiore della curva ed un aumento dell’ampiezza dei picchi nella parte alta. È probabile, quindi, che la variabilità paleoambientale riscontrata nella parte bassa sia probabilmente legata alla sovrapposizione di fattori locali rispetto ai cambiamenti climatici globali, mentre, nella parte alta, le maggiori oscillazioni in ampiezza dei valori di insolazione guidarono i cambiamenti paleoambientali alla scala dell’intero bacino mediterraneo. The ostracod assemblages with Paratethyan affinity from several late Messinian Lago-Mare deposits located in Italy and Crete (Greece) have been examined and the community analyses (number of species, Margalef and Shannon-Wiener indexes) and auto/ synecological analyses have been performed on them. The results show that, generally, in the lower portion the post-evaporitic Messinian was characterised by unstable environments, which hosted poor ostracod communities characterised by low diversity, while in the upper portion the environmental conditions were more stable, allowing the subdivision of the environment hyperspace in several different niches and, thus, supporting high-diversity ostracod communities. Anyway, the correlation of the boundary between low- and high-diversity ostracod assemblages through the studied successions has shown to be heterochronous, probably because it is due both to local and regional factors. A more detailed palaeoenvironmental reconstruction across the late Messinian Lago-Mare successions showed that, while in the lower portion the palaeoenvironments are rather disomogeneous, even if investigated in nearby sections, in the upper part a general trend towards a deepening and freshening followed by a new salinity increase and depth decrease has been recognized. The palaeoenvironmental variability of the lower part probably was related to the superimposition of local factors on global climatic forcing, while in the upper part the high amplitude insolation peaks drove the palaeoenvironmental changes at a regional scale.

In the Crete Island, late Messinian Lago-Mare facies are not well known. At present, the occurrence in Crete of the uppermost Messinian post evaporitic deposits is a matter of debate. According to several authors, the well-known late Messinian Lago-Mare facies does not occur in Crete. In this paper the preliminary results obtained from the biostratigraphical analysis of some sections sampled in the Messara` Plain will be shown. Nearby Faneromeni and Ano Akria villages, the Miocene/Pliocene boundary is well exposed. There, gypsum-bearing clay, laminated microcrystalline gypsum and gypsum-rudites characterize the evaporitic deposits of the Messinian stage. In these areas, above the Messinian evaporite, post-evaporitic fine-laminated polychrome clays, with intercalations of sandstones and conglomerates, have been found. In both the Faneromeni and Ano Akria area, the Pliocene grey clays and conglomerates rest unconformably on the uppermost Messinian post-evaporitic deposits. A 20 cm-spaced sampling has been performed in both the sections, for more than 100 samples collected. The results of the micropaleontological analysis performed on the Faneromeni and Ano Akria sections point to the occurrence of ostracod assemblages containing: Loxocauda limata (Schneider in Agalarova et al.), Loxocauda sp., Cytherura pyrama Schneider, Cyprideis anlavauxensis Carbonnel, Cyprideis agrigentina Decima, Amnicythere palimpsesta (Livental), Amnicythere propinqua (Livental), Amnicythere accicularia (Olteanu), Amnicythere costata (Olteanu), Amnicythere multituberculata (Livental), Amnicythere sp. D (Miculan in Bassetti et al.), Amnicythere sp. 2 Gliozzi and Grossi, Amnicythere sp., Euxinocythere (Maeotocythere) praebaquana (Livental in Agalarova et al.), Mediocytherideini indet., Pontoniella pontica (Agalarova), Camptocypria sp. 1 Gliozzi and Grossi, Caspiocypris sp., Zalanyiella venusta (Zalanyi), Tyrrhenocythere sp., Loxoconcha rhombovalis Pokorny, Loxoconcha eichwaldi Livental, Loxoconcha sp. A (Miculan in Bassetti et al.), Loxocorniculina djafarovi (Schneider in Suzin). In the analysed samples, reworked planktonic foraminifers and well-preserved charophyte gyrogonites have been also found. The ostracod assemblages found in the Messara` Plain belong to the Loxocorniculina djafarovi Zone (sensu Carbonnel, 1978), which characterizes the uppermost Messinian deposits of the whole Mediterranean Basin. At that time, the well-known Lago-Mare biofacies was also widespread on the Crete Island. The presence of Paratethyan ostracods in the post-evaporitic Messinian deposits of both Faneromeni and Ano Akria sections suggests that in the Crete Island the latest Messinian sedimentation took place in brackish water palaeoenvironments.

Dans l’ıˆle de Cre`te, les facie`s du Lago Mare du Messinien supe´rieur ne sont pas bien connus. Actuellement, la pre´sence dans l’Iˆle de Cre`te des de´poˆ ts post-e´vaporitiques du Messinien supe´rieur est une question qui fait de´bat. Dans ce travail, on pre´sente les re´sultats pre´liminaires des analyses biostratigraphiques re´alise´es sur des e´chantillons pre´leve´s dans des affleurements de la Plaine de Messara`. Pre`s de Faneromeni et Ano Akria, la limite Mioce`ne/Plioce`ne est bien observable. Ici, les de´poˆ ts e´vaporitiques du Messinien sont caracte´rise´s par des argiles contenant du gypse, du gypse microcristallin lamine´ et des gypsorudites. Dans ces zones, on a trouve´ au-dessus des e´vaporites du Messinien des argiles polychromes finement lamine´es. Les argiles grises et les conglome´rats du Plioce`ne se trouvent discordants sur les de´poˆts post-e´vaporitiques du Messinien supe´rieur a` Faneromeni comme a` Ano Akria. Dans les deux coupes, l’e´chantillonnage a e´te´ re´alise´ tous les 20 cm (total de 100 e´chantillons). Les re´sultats des analyses micropale´ontologiques montrent la pre´sence des ostracodes suivants : Loxocauda limata (Schneider in Agalarova et al.), Loxocauda sp., Cytherura pyrama Schneider, Cyprideis anlavauxensis Carbonnel, Cyprideis agrigentina Decima, Amnicythere palimpsesta (Livental), Amnicythere propinqua (Livental), Amnicythere accicularia (Olteanu), Amnicythere costata (Olteanu), Amnicythere multituberculata (Livental), Amnicythere sp. D (Miculan in Bassetti et al.), Amnicythere sp. 2 Gliozzi and Grossi, Amnicythere sp., Euxinocythere (Maeotocythere) praebaquana (Livental in Agalarova et al.), Mediocytherideini indet., Pontoniella pontica (Agalarova), Camptocypria sp. 1 Gliozzi and Grossi, Caspiocypris sp., Zalanyiella venusta (Zalanyi), Tyrrhenocythere sp., Loxoconcha rhombovalis Pokorny, Loxoconcha eichwaldi Livental, Loxoconcha sp. A (Miculan in Bassetti et al.), Loxocorniculina djafarovi (Schneider in Suzin). On a trouve´ aussi dans les e´chantillons analyse´s des foraminife`res planctoniques remanie´s et des gyrogonites de Characeae bien conserve´s. Les associations d’ostracodes trouve´es dans la Plaine de Messara` appartiennent a` la Zone a` Loxocorniculina djafarovi (sensu Carbonnel, 1978), qui caracte´rise les de´poˆ ts du Messinien supe´rieur dans tout le bassin me´diterrane´en. A cette pe´riode, le facie`s bien connu du Lago Mare existait aussi dans l’Iˆle de Cre`te. La pre´sence des ostracodes parate´thysiens dans les de´poˆ ts post-e´vaporitiques du Messinien, a` Faneromeni et a` Ano Akria, sugge`re que des conditions de se´dimentation sous-aquatique en milieu saumaˆtre se sont de´veloppe´es en Cre`te pendant le Messinien supe´rieur. In the Crete Island, late Messinian Lago-Mare facies are not well known. At present, the occurrence in Crete of the uppermost Messinian post evaporitic deposits is a matter of debate. According to several authors, the well-known late Messinian Lago-Mare facies does not occur in Crete. In this paper the preliminary results obtained from the biostratigraphical analysis of some sections sampled in the Messara` Plain will be shown. Nearby Faneromeni and Ano Akria villages, the Miocene/Pliocene boundary is well exposed. There, gypsum-bearing clay, laminated microcrystalline gypsum and gypsum-rudites characterize the evaporitic deposits of the Messinian stage. In these areas, above the Messinian evaporite, post-evaporitic fine-laminated polychrome clays, with intercalations of sandstones and conglomerates, have been found. In both the Faneromeni and Ano Akria area, the Pliocene grey clays and conglomerates rest unconformably on the uppermost Messinian post-evaporitic deposits. A 20 cm-spaced sampling has been performed in both the sections, for more than 100 samples collected. The results of the micropaleontological analysis performed on the Faneromeni and Ano Akria sections point to the occurrence of ostracod assemblages containing: Loxocauda limata (Schneider in Agalarova et al.), Loxocauda sp., Cytherura pyrama Schneider, Cyprideis anlavauxensis Carbonnel, Cyprideis agrigentina Decima, Amnicythere palimpsesta (Livental), Amnicythere propinqua (Livental), Amnicythere accicularia (Olteanu), Amnicythere costata (Olteanu), Amnicythere multituberculata (Livental), Amnicythere sp. D (Miculan in Bassetti et al.), Amnicythere sp. 2 Gliozzi and Grossi, Amnicythere sp., Euxinocythere (Maeotocythere) praebaquana (Livental in Agalarova et al.), Mediocytherideini indet., Pontoniella pontica (Agalarova), Camptocypria sp. 1 Gliozzi and Grossi, Caspiocypris sp., Zalanyiella venusta (Zalanyi), Tyrrhenocythere sp., Loxoconcha rhombovalis Pokorny, Loxoconcha eichwaldi Livental, Loxoconcha sp. A (Miculan in Bassetti et al.), Loxocorniculina djafarovi (Schneider in Suzin). In the analysed samples, reworked planktonic foraminifers and well-preserved charophyte gyrogonites have been also found. The ostracod assemblages found in the Messara` Plain belong to the Loxocorniculina djafarovi Zone (sensu Carbonnel, 1978), which characterizes the uppermost Messinian deposits of the whole Mediterranean Basin. At that time, the well-known Lago-Mare biofacies was also widespread on the Crete Island. The presence of Paratethyan ostracods in the post-evaporitic Messinian deposits of both Faneromeni and Ano Akria sections suggests that in the Crete Island the latest Messinian sedimentation took place in brackish water palaeoenvironments.

The Mondragone 1 well, drilled in 1968 by Agip, for hydrocarbon exploration, cut across siliciclastic fine-to-coarse-grained upper Miocene–Quaternary deposits, for a total depth of 2002 m. Thirteen cores have been recovered from 495 down to 2002 m. This paper deals with both the results of the biostratigraphical analyses performed on a new sampling of the cores and the significance of the well stratigraphy in the context of the late Messinian Lago–Mare episode in central Mediterranean. The Lago–Mare biofacies has been characterised from 675 down to 2002 m by the ostracod assemblages that are made of species belonging to the Loxocorniculina djafarovi Zone, as defined by Carbonnel [Carbonnel, G., 1978. La zone a Loxoconcha djaffarovi Schneider (Ostracoda,Miocène supérieur) ou leMessinien de laVallée du Rhône. Rev.Micropaleontol. 21, 106–118.] (e.g. L. djafarovi, Loxoconcha eichwaldi, Cyprideis anlavauxensis, Amnicythere palimpsesta, Zalanyiella venusta). Thus, the Lago–Mare deposits have a true thickness of about 938 m since the strata show a mean dip value of 45°. Similar thickness (530 m) has been measured in the pre- Pliocene sediments drilled at ODP Site 652, which can be correlated withMondragone 1 by the occurrence of brackish-water forms. In both these areas syn-rift depositional processes have been suggested to explain the unusual thickness of the late Messinian sediments. Data from seismic lines have been used to reconstruct the geometry and the structural setting of the Garigliano Basin during the latest Messinian. Moreover, the analysis of the SP log integrated with the palaeoecological indications from the ostracod assemblages allows us to suggest a possible sequence stratigraphy evolution of the Garigliano Basin during the late Messinian Lago–Mare episode. Different tectonic behaviour with differences in subsidence rates between the northern and the southern Tyrrhenian Basin have been suggested since the uppermost Messinian syn-rift clastic wedges recognized in the onshore of northern Latium and Tuscany show thickness lower than that drilled at the ODP Site 652 and at the Mondragone 1 well.

The genus Tavanicythere was established in 1980 by Bossio on the basis of several valves recovered in the Lower Messinian brackish deposits of the Radicondoli area (Volterra Basin, Tuscany, central Italy). Three species were included in this genus: Tavanicythere lepida Bossio (the type species), Tavanicythere etrusca Bossio and Tavanicythere pulchra Bossio. Since then, many other specimens referable to Tavanicythere have been collected from several Neogene Tuscany basins (Volterra, Valdelsa, Cinigiano-Baccinello), but no specific identifications were carried out and they were generally reported in literature as Tavanicythere sp. In this paper we have revised all the collected material. Up to 15 different new taxa have been recognised, even if only 11 are formally established herein as new species, due, in some cases, to the scarcity of valves: Tavanicythere varieornata nov. sp., Tavanicythere persculpta nov. sp., Tavanicythere posteroalata nov. sp. Tavanicythere sulcata nov. sp., Tavanicythere magna nov. sp., Tavanicythere nodosa nov. sp., Tavanicythere armata nov. sp., Tavanicythere ioachinoi nov. sp., Tavanicythere julianii nov. sp., Tavanicythere parva nov. sp. and Tavanicythere irregularis nov. sp. Only few species of Tavanicythere appear to be distributed in different basins, the majority being confined to one basin only. This could be due to particular brackish environmental conditions that triggered basin endemisms. The recovery of new Tavanicythere species lead to enlarge the stratigraphical distribution of this genus, prior limited to the Early Messinian, to the time interval Late Tortonian-Messinian. Tavanicythere seems to be widespread only in the Mediterranean basin and, in particular, in Italy (Tuscany). At present, outside of Italy it has been collected only from the Late Messinian brackish deposits of the Sorbas basin (SE Spain).

The Sr/Ca and Mg/Ca ratios of fossil ostracod and mollusc shells from a Late Miocene (Early Messinian) lacustrine sequence in the Velona Basin (central Apennines, Italy) were used to calculate the Sr/Ca and Mg/Ca of waters in which these taxa lived. Sr/Ca of these waters were always higher than the Sr/Ca calculated for the Messinian seawater, despite the broad salinity ranges(fresh water-oligo/mesohaline) inferred from the paleontological analyses. The estimated Mg/Cawater from the Velona samples are below the Mg/Ca value for coeval seawater even though they represent relatively high values when compared with many nonmarine waters. The salinity variations of the Velona lacustrine system, recorded by changes in faunal assemblages, are linked to variable inputs of Na'Cl from deep groundwaters and are not reflected in significant changes in Sr/Ca and Mg/Ca of the waters calculated from shell chemistry. The combination of d18O signatures and Sr isotopic ratios from molluscs from the Velona Basin suggests a non-marine environment. During some episodes of the lake history, given the saline inputs, the waters in the lake would attain a large solute concentration (oligo to mesohaline), although they retained the meteoric d18O signature. We compare the paleohydrochemical inferences from the studied sequence with other Messinian records, and we show the importance ofcombining paleoecological and geochemical proxies to obtain consistent paleoenvironmental reconstructions.